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Re: [Small4-strokeEngines] Re: flywheel butchering

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  • Peter Walker
    Hello Kev   The taper is easy If you have access to a lathe just use the taper plug Creep up to the taper using the bump method on the compound slide Once
    Message 1 of 22 , Apr 24, 2013
    • 0 Attachment
      Hello Kev 
       The taper is easy If you have access to a lathe just use the taper plug Creep up to the taper using the bump method on the compound slide Once you have the taper correct face the small end to be level with the small end of the taper for use as a finished diameter The use an upside down boring bar (tip facing awau from you) to cut the taper big end to small end and then turn up the rest
       Have fun
      Peter


      From: Kev A <kevin@...>
      To: Small4-strokeEngines@yahoogroups.com
      Sent: Thursday, April 25, 2013 6:03 AM
      Subject: [Small4-strokeEngines] Re: flywheel butchering

       
      The high quality of the replies from you folk says everything; I aren't time-served as a machinist but a fitter, and didn't realise how much there was to an apparently simple task such as creating a taper.

      The tip about cutter height being exactly level with centreline, to avoid a curved taper, hadn't hit until it was pointed out, thanks.

      Thing is, the centre region of a flywheel is the least, and the rim the most useful, as radius of action times weight (OK mass, but I'm trying not to be an engineering snob) is the measure of effectiveness.

      When you see a dirty great lump of iron on the crankshaft, it seemed to make sense to rip out the middle and swap it for alloy. Downside is the timing will need carefully setting up, but that looks easy enough with a clock gauge to find top dead centre, and some measurements taken from the stock wheel's magnet location, then bolt the rim onto a new alloy middle in the same relationship.

      Maybe I should leave the flywheel alone now as the alloy ones aren't chap and lack generator magnets, unless the can be prised off and stuck into an alloy wheel. All that risk and expense looked just about viable, but if the taper is trickier than it looks maybe it is best to look elsewhere to lose weight.

      Back to the drawing board...

      Cheers

      Kev

      --- In Small4-strokeEngines@yahoogroups.com, ron ohler <ohler_ron@...> wrote:
      >
      > Hi,
      > There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
      >  
      > A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe
      > will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
      > If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
      > Best,
      > RonO 
      > --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:
      >
      >
      > From: Peter Walker <peterwalker58@...>
      > Subject: Re: [Small4-strokeEngines] flywheel butchering
      > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
      > Date: Wednesday, April 24, 2013, 1:07 AM
      >
      >
      >
      >  
      >
      >
      >
      >
      >
      > Hello Ron
      >  I have not seen that one Can you explain it further
      > Even on CNCs we used plug gauges as a setup and checking tool 
      > Peter
      >
      >
      >
      >
      >
      >
      >
      >
      > From: ron ohler <ohler_ron@...>
      > To: Small4-strokeEngines@yahoogroups.com
      > Sent: Wednesday, April 24, 2013 11:44 AM
      > Subject: Re: [Small4-strokeEngines] flywheel butchering
      >
      >
      >
      >
      >  
      >
      >
      >
      >
      >
      > Hi,
      > turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
      > Best,
      > RonO
      >
      >
      > --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:
      >
      >
      > From: Peter Walker <peterwalker58@...>
      > Subject: Re: [Small4-strokeEngines] flywheel butchering
      > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
      > Date: Tuesday, April 23, 2013, 10:43 PM
      >
      >
      >
      >  
      >
      >
      >
      > Hello George
      >  I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
      > Peter
      >
      >
      >
      >
      >
      >
      > From: George Bearden <gab16@...>
      > To: Small4-strokeEngines@yahoogroups.com
      > Sent: Wednesday, April 24, 2013 9:24 AM
      > Subject: RE: [Small4-strokeEngines] flywheel butchering
      >
      >
      >
      >
      >  
      >
      >
      >
      >
      >
      >
      >
      >
      > > A good shop will turn a taper plug to match your flywheel
      >  
      > I'm glad you smart people are on here!
      >  
      >



    • ron ohler
      Hi Peter, I make prop hubs for some military engines, When it wasn t certain what the crank taper was I just set the crank shaft up in a lathe and
      Message 2 of 22 , Apr 24, 2013
      • 0 Attachment
        Hi Peter,
        I make prop hubs for some military engines, When it wasn't certain what the crank taper was I just set the crank shaft up in a lathe and measured the taper with dial indicators as I described.
        In that instance the crankshaft was easier to work with to determine the taper angle than the rather large flywheel. I have a lathe with a DRO. DRO installations generally only give the X and Z axis references. I can have a 3rd axis on my DRO but don't bother. I figured it was easier to tell folks how to do it with indicators. I've seen feeler gauge measurement screwed up by folks who really don't know how to "feel" with a feeler gauge. For that matter I guess the same should be said of mounting dial indicators and getting inconsistent readings due to lack of proper set up on them too.
        Best,
        RonO
         
         

        --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

        From: Peter Walker <peterwalker58@...>
        Subject: Re: [Small4-strokeEngines] flywheel butchering
        To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
        Date: Wednesday, April 24, 2013, 6:44 PM

         
        Hello
        The procedure youdescribed is to set the taper turning or compound slide to an known angle The problem here is the flywheel has an unknown taper that has to be replicated You could measure the taper in the flywheel with the method you suggest then set up the taper turn using the same method or set the taper turn to the flywheel taper using a dial gauge or turn a tapered plug gauge 
         For all that if the lathe has a digital readout you can just use a boring bar and a feeler gauge to get it done 
        The method comes down to what equipment you have the machinists skill level and the need to have a number for later use 
        Peter
         


        From: ron ohler <ohler_ron@...>
        To: Small4-strokeEngines@yahoogroups.com
        Sent: Wednesday, April 24, 2013 9:16 PM
        Subject: Re: [Small4-strokeEngines] flywheel butchering

         
        Hi,
        There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
         
        A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
        If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
        Best,
        RonO 
        --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

        From: Peter Walker <peterwalker58@...>
        Subject: Re: [Small4-strokeEngines] flywheel butchering
        To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
        Date: Wednesday, April 24, 2013, 1:07 AM

         
        Hello Ron
         I have not seen that one Can you explain it further
        Even on CNCs we used plug gauges as a setup and checking tool 
        Peter



        From: ron ohler <ohler_ron@...>
        To: Small4-strokeEngines@yahoogroups.com
        Sent: Wednesday, April 24, 2013 11:44 AM
        Subject: Re: [Small4-strokeEngines] flywheel butchering

         
        Hi,
        turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
        Best,
        RonO


        --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:

        From: Peter Walker <peterwalker58@...>
        Subject: Re: [Small4-strokeEngines] flywheel butchering
        To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
        Date: Tuesday, April 23, 2013, 10:43 PM

         
        Hello George
         I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
        Peter


        From: George Bearden <gab16@...>
        To: Small4-strokeEngines@yahoogroups.com
        Sent: Wednesday, April 24, 2013 9:24 AM
        Subject: RE: [Small4-strokeEngines] flywheel butchering

         
        > A good shop will turn a taper plug to match your flywheel
         
        I'm glad you smart people are on here!
         






      • Peter Walker
        Hello Ron No method is wrong but if the skill level (lower) and time (lots) a taper plug is simple   A skilled machinist would have any method done in 30
        Message 3 of 22 , Apr 24, 2013
        • 0 Attachment
          Hello Ron
          No method is wrong but if the skill level (lower) and time (lots) a taper plug is simple 
           A skilled machinist would have any method done in 30 minutes no matter what method was used 
          I would do a plug on my CNC lathe and just move the U till i had it right then go U- to do the tapered bore 
          S1000M3
          G0 X35.0 Z5.0 T0101
          G01 X30.0 Z0 F0.15
          Z-30.0 U5.0 
          Z-35.0
          G0 U1.0 Z5.0
          G28 X200.0 Z200.0 
          M30
          (metric) 
           this would give a 30 diameter at the small end and 35 at the large end and a 30 long taper in 30 seconds run time

          Peter



          From: ron ohler <ohler_ron@...>
          To: Small4-strokeEngines@yahoogroups.com
          Sent: Thursday, April 25, 2013 7:13 AM
          Subject: Re: [Small4-strokeEngines] flywheel butchering

           
          Hi Peter,
          I make prop hubs for some military engines, When it wasn't certain what the crank taper was I just set the crank shaft up in a lathe and measured the taper with dial indicators as I described.
          In that instance the crankshaft was easier to work with to determine the taper angle than the rather large flywheel. I have a lathe with a DRO. DRO installations generally only give the X and Z axis references. I can have a 3rd axis on my DRO but don't bother. I figured it was easier to tell folks how to do it with indicators. I've seen feeler gauge measurement screwed up by folks who really don't know how to "feel" with a feeler gauge. For that matter I guess the same should be said of mounting dial indicators and getting inconsistent readings due to lack of proper set up on them too.
          Best,
          RonO
           
           

          --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

          From: Peter Walker <peterwalker58@...>
          Subject: Re: [Small4-strokeEngines] flywheel butchering
          To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
          Date: Wednesday, April 24, 2013, 6:44 PM

           
          Hello
          The procedure youdescribed is to set the taper turning or compound slide to an known angle The problem here is the flywheel has an unknown taper that has to be replicated You could measure the taper in the flywheel with the method you suggest then set up the taper turn using the same method or set the taper turn to the flywheel taper using a dial gauge or turn a tapered plug gauge 
           For all that if the lathe has a digital readout you can just use a boring bar and a feeler gauge to get it done 
          The method comes down to what equipment you have the machinists skill level and the need to have a number for later use 
          Peter
           


          From: ron ohler <ohler_ron@...>
          To: Small4-strokeEngines@yahoogroups.com
          Sent: Wednesday, April 24, 2013 9:16 PM
          Subject: Re: [Small4-strokeEngines] flywheel butchering

           
          Hi,
          There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
           
          A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
          If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
          Best,
          RonO 
          --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

          From: Peter Walker <peterwalker58@...>
          Subject: Re: [Small4-strokeEngines] flywheel butchering
          To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
          Date: Wednesday, April 24, 2013, 1:07 AM

           
          Hello Ron
           I have not seen that one Can you explain it further
          Even on CNCs we used plug gauges as a setup and checking tool 
          Peter



          From: ron ohler <ohler_ron@...>
          To: Small4-strokeEngines@yahoogroups.com
          Sent: Wednesday, April 24, 2013 11:44 AM
          Subject: Re: [Small4-strokeEngines] flywheel butchering

           
          Hi,
          turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
          Best,
          RonO


          --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:

          From: Peter Walker <peterwalker58@...>
          Subject: Re: [Small4-strokeEngines] flywheel butchering
          To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
          Date: Tuesday, April 23, 2013, 10:43 PM

           
          Hello George
           I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
          Peter


          From: George Bearden <gab16@...>
          To: Small4-strokeEngines@yahoogroups.com
          Sent: Wednesday, April 24, 2013 9:24 AM
          Subject: RE: [Small4-strokeEngines] flywheel butchering

           
          > A good shop will turn a taper plug to match your flywheel
           
          I'm glad you smart people are on here!
           








        • Alan Stockdale
          I am pretty sure that the engine running is not dependent on using the original magnets, magnetism is magnetism and varies considerably over the life of the
          Message 4 of 22 , Apr 24, 2013
          • 0 Attachment
            I am pretty sure that the engine running is not dependent on using the original magnets, *:) happy magnetism is magnetism and varies considerably over the life of the magnet although there are plenty of parameters that describe and specify magnetism including iron filing patterns for those without gauss meters.

            Perhaps a whole alloy flywheel with a plastic fan attached and embedded neodymium magnets which come in all shapes and sizes, some can be glued into a round hole on the perimeter, with equal weight provided opposite for balance and of course the magnets placed at the same spacings as the original small boat anchor flywheel would be a possible route. The concept of a disc with a boss that allowed timing adjustment ala automotive belt driven cam timing style slots might help too if the boss has a keyway.

            Alan

             
             


            From: Kev A <kevin@...>
            To: Small4-strokeEngines@yahoogroups.com
            Sent: Thursday, 25 April 2013 8:03 AM
            Subject: [Small4-strokeEngines] Re: flywheel butchering

            The high quality of the replies from you folk says everything; I aren't time-served as a machinist but a fitter, and didn't realise how much there was to an apparently simple task such as creating a taper.

            The tip about cutter height being exactly level with centreline, to avoid a curved taper, hadn't hit until it was pointed out, thanks.

            Thing is, the centre region of a flywheel is the least, and the rim the most useful, as radius of action times weight (OK mass, but I'm trying not to be an engineering snob) is the measure of effectiveness.

            When you see a dirty great lump of iron on the crankshaft, it seemed to make sense to rip out the middle and swap it for alloy. Downside is the timing will need carefully setting up, but that looks easy enough with a clock gauge to find top dead centre, and some measurements taken from the stock wheel's magnet location, then bolt the rim onto a new alloy middle in the same relationship.

            Maybe I should leave the flywheel alone now as the alloy ones aren't chap and lack generator magnets, unless the can be prised off and stuck into an alloy wheel. All that risk and expense looked just about viable, but if the taper is trickier than it looks maybe it is best to look elsewhere to lose weight.

            Back to the drawing board...

            Cheers

            Kev

            --- In Small4-strokeEngines@yahoogroups.com, ron ohler <ohler_ron@...> wrote:
            >
            > Hi,
            > There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
            >  
            > A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe
            >  will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
            > If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
            > Best,
            > RonO 
            > --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:
            >
            >
            > From: Peter Walker <peterwalker58@...>
            > Subject: Re: [Small4-strokeEngines] flywheel butchering
            > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
            > Date: Wednesday, April 24, 2013, 1:07 AM
            >
            >
            >
            >  
            >
            >
            >
            >
            >
            > Hello Ron
            >  I have not seen that one Can you explain it further
            > Even on CNCs we used plug gauges as a setup and checking tool 
            > Peter
            >
            >
            >
            >
            >
            >
            >
            >
            > From: ron ohler <ohler_ron@...>
            > To: Small4-strokeEngines@yahoogroups.com
            > Sent: Wednesday, April 24, 2013 11:44 AM
            > Subject: Re: [Small4-strokeEngines] flywheel butchering
            >
            >
            >
            >
            >  
            >
            >
            >
            >
            >
            > Hi,
            > turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
            > Best,
            > RonO
            >
            >
            > --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:
            >
            >
            > From: Peter Walker <peterwalker58@...>
            > Subject: Re: [Small4-strokeEngines] flywheel butchering
            > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
            > Date: Tuesday, April 23, 2013, 10:43 PM
            >
            >
            >
            >  
            >
            >
            >
            > Hello George
            >  I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
            > Peter
            >
            >
            >
            >
            >
            >
            > From: George Bearden <gab16@...>
            > To: Small4-strokeEngines@yahoogroups.com
            > Sent: Wednesday, April 24, 2013 9:24 AM
            > Subject: RE: [Small4-strokeEngines] flywheel butchering
            >
            >
            >
            >
            >  
            >
            >
            >
            >
            >
            >
            >
            >
            > > A good shop will turn a taper plug to match your flywheel
            >  
            > I'm glad you smart people are on here!
            >  
            >




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          • ron ohler
            Hi Peter, The post started out as being a reply to the fact that their machinist needed to know the actual angle rather than the linear dimensions. Nearly
            Message 5 of 22 , Apr 24, 2013
            • 0 Attachment
              Hi Peter,
              The post started out as being a reply to the fact that their machinist needed to know the actual angle rather than the linear dimensions. Nearly certainly because all they wanted to do was set the compound angle and presume that it would be accurate. While commonplace - this is not an accurate method as it assumes the machine is was or is still accurate and has not settled, worn or twisted over time. I can't determine if they ever checked the compound angle markings for
               accuracy,
               Best,
              RonO
              --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

              From: Peter Walker <peterwalker58@...>
              Subject: Re: [Small4-strokeEngines] flywheel butchering
              To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
              Date: Wednesday, April 24, 2013, 8:12 PM

               
              Hello Ron
              No method is wrong but if the skill level (lower) and time (lots) a taper plug is simple 
               A skilled machinist would have any method done in 30 minutes no matter what method was used 
              I would do a plug on my CNC lathe and just move the U till i had it right then go U- to do the tapered bore 
              S1000M3
              G0 X35.0 Z5.0 T0101
              G01 X30.0 Z0 F0.15
              Z-30.0 U5.0 
              Z-35.0
              G0 U1.0 Z5.0
              G28 X200.0 Z200.0 
              M30
              (metric) 
               this would give a 30 diameter at the small end and 35 at the large end and a 30 long taper in 30 seconds run time

              Peter



              From: ron ohler <ohler_ron@...>
              To: Small4-strokeEngines@yahoogroups.com
              Sent: Thursday, April 25, 2013 7:13 AM
              Subject: Re: [Small4-strokeEngines] flywheel butchering

               
              Hi Peter,
              I make prop hubs for some military engines, When it wasn't certain what the crank taper was I just set the crank shaft up in a lathe and measured the taper with dial indicators as I described.
              In that instance the crankshaft was easier to work with to determine the taper angle than the rather large flywheel. I have a lathe with a DRO. DRO installations generally only give the X and Z axis references. I can have a 3rd axis on my DRO but don't bother. I figured it was easier to tell folks how to do it with indicators. I've seen feeler gauge measurement screwed up by folks who really don't know how to "feel" with a feeler gauge. For that matter I guess the same should be said of mounting dial indicators and getting inconsistent readings due to lack of proper set up on them too.
              Best,
              RonO
               
               

              --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

              From: Peter Walker <peterwalker58@...>
              Subject: Re: [Small4-strokeEngines] flywheel butchering
              To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
              Date: Wednesday, April 24, 2013, 6:44 PM

               
              Hello
              The procedure youdescribed is to set the taper turning or compound slide to an known angle The problem here is the flywheel has an unknown taper that has to be replicated You could measure the taper in the flywheel with the method you suggest then set up the taper turn using the same method or set the taper turn to the flywheel taper using a dial gauge or turn a tapered plug gauge 
               For all that if the lathe has a digital readout you can just use a boring bar and a feeler gauge to get it done 
              The method comes down to what equipment you have the machinists skill level and the need to have a number for later use 
              Peter
               


              From: ron ohler <ohler_ron@...>
              To: Small4-strokeEngines@yahoogroups.com
              Sent: Wednesday, April 24, 2013 9:16 PM
              Subject: Re: [Small4-strokeEngines] flywheel butchering

               
              Hi,
              There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
               
              A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
              If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
              Best,
              RonO 
              --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:

              From: Peter Walker <peterwalker58@...>
              Subject: Re: [Small4-strokeEngines] flywheel butchering
              To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
              Date: Wednesday, April 24, 2013, 1:07 AM

               
              Hello Ron
               I have not seen that one Can you explain it further
              Even on CNCs we used plug gauges as a setup and checking tool 
              Peter



              From: ron ohler <ohler_ron@...>
              To: Small4-strokeEngines@yahoogroups.com
              Sent: Wednesday, April 24, 2013 11:44 AM
              Subject: Re: [Small4-strokeEngines] flywheel butchering

               
              Hi,
              turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
              Best,
              RonO


              --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:

              From: Peter Walker <peterwalker58@...>
              Subject: Re: [Small4-strokeEngines] flywheel butchering
              To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
              Date: Tuesday, April 23, 2013, 10:43 PM

               
              Hello George
               I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
              Peter


              From: George Bearden <gab16@...>
              To: Small4-strokeEngines@yahoogroups.com
              Sent: Wednesday, April 24, 2013 9:24 AM
              Subject: RE: [Small4-strokeEngines] flywheel butchering

               
              > A good shop will turn a taper plug to match your flywheel
               
              I'm glad you smart people are on here!
               








            • Peter Walker
              Hello 12 Ferrite Magnets, ceramic magnets 2 * 1 * 1/2 (50 * 25 * 12 mm) $15.55  Ebay 130891151819 They end up 3/8 thick at the ends if turned to a 8 on
              Message 6 of 22 , Apr 24, 2013
              • 0 Attachment
                Hello

                12 Ferrite Magnets, ceramic magnets 2" * 1" * 1/2" (50 * 25 * 12 mm) $15.55 

                Ebay 130891151819
                They end up 3/8 thick at the ends if turned to a 8 "on the outside of a flywheel You have plenty to play with to get it right
                Peter


                From: Alan Stockdale <bluejeans725@...>
                To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                Sent: Thursday, April 25, 2013 10:41 AM
                Subject: Re: [Small4-strokeEngines] Re: flywheel butchering

                 
                I am pretty sure that the engine running is not dependent on using the original magnets, *:) happy magnetism is magnetism and varies considerably over the life of the magnet although there are plenty of parameters that describe and specify magnetism including iron filing patterns for those without gauss meters.

                Perhaps a whole alloy flywheel with a plastic fan attached and embedded neodymium magnets which come in all shapes and sizes, some can be glued into a round hole on the perimeter, with equal weight provided opposite for balance and of course the magnets placed at the same spacings as the original small boat anchor flywheel would be a possible route. The concept of a disc with a boss that allowed timing adjustment ala automotive belt driven cam timing style slots might help too if the boss has a keyway.

                Alan

                 
                 


                From: Kev A <kevin@...>
                To: Small4-strokeEngines@yahoogroups.com
                Sent: Thursday, 25 April 2013 8:03 AM
                Subject: [Small4-strokeEngines] Re: flywheel butchering

                The high quality of the replies from you folk says everything; I aren't time-served as a machinist but a fitter, and didn't realise how much there was to an apparently simple task such as creating a taper.

                The tip about cutter height being exactly level with centreline, to avoid a curved taper, hadn't hit until it was pointed out, thanks.

                Thing is, the centre region of a flywheel is the least, and the rim the most useful, as radius of action times weight (OK mass, but I'm trying not to be an engineering snob) is the measure of effectiveness.

                When you see a dirty great lump of iron on the crankshaft, it seemed to make sense to rip out the middle and swap it for alloy. Downside is the timing will need carefully setting up, but that looks easy enough with a clock gauge to find top dead centre, and some measurements taken from the stock wheel's magnet location, then bolt the rim onto a new alloy middle in the same relationship.

                Maybe I should leave the flywheel alone now as the alloy ones aren't chap and lack generator magnets, unless the can be prised off and stuck into an alloy wheel. All that risk and expense looked just about viable, but if the taper is trickier than it looks maybe it is best to look elsewhere to lose weight.

                Back to the drawing board...

                Cheers

                Kev

                --- In Small4-strokeEngines@yahoogroups.com, ron ohler <ohler_ron@...> wrote:
                >
                > Hi,
                > There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
                >  
                > A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe
                >  will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
                > If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
                > Best,
                > RonO 
                > --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:
                >
                >
                > From: Peter Walker <peterwalker58@...>
                > Subject: Re: [Small4-strokeEngines] flywheel butchering
                > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                > Date: Wednesday, April 24, 2013, 1:07 AM
                >
                >
                >
                >  
                >
                >
                >
                >
                >
                > Hello Ron
                >  I have not seen that one Can you explain it further
                > Even on CNCs we used plug gauges as a setup and checking tool 
                > Peter
                >
                >
                >
                >
                >
                >
                >
                >
                > From: ron ohler <ohler_ron@...>
                > To: Small4-strokeEngines@yahoogroups.com
                > Sent: Wednesday, April 24, 2013 11:44 AM
                > Subject: Re: [Small4-strokeEngines] flywheel butchering
                >
                >
                >
                >
                >  
                >
                >
                >
                >
                >
                > Hi,
                > turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
                > Best,
                > RonO
                >
                >
                > --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:
                >
                >
                > From: Peter Walker <peterwalker58@...>
                > Subject: Re: [Small4-strokeEngines] flywheel butchering
                > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                > Date: Tuesday, April 23, 2013, 10:43 PM
                >
                >
                >
                >  
                >
                >
                >
                > Hello George
                >  I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
                > Peter
                >
                >
                >
                >
                >
                >
                > From: George Bearden <gab16@...>
                > To: Small4-strokeEngines@yahoogroups.com
                > Sent: Wednesday, April 24, 2013 9:24 AM
                > Subject: RE: [Small4-strokeEngines] flywheel butchering
                >
                >
                >
                >
                >  
                >
                >
                >
                >
                >
                >
                >
                >
                > > A good shop will turn a taper plug to match your flywheel
                >  
                > I'm glad you smart people are on here!
                >  
                >




                ------------------------------------


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              • Alan Muller
                Regardless of how you set up the taper cut, I d expect to have to check it with blue dye and sneak up on full contact.... As I recall, flywheel effect (polar
                Message 7 of 22 , Apr 25, 2013
                • 0 Attachment
                  Regardless of how you set up the taper cut, I'd expect to have to check it with blue dye and sneak up on full contact....

                  As I recall, flywheel effect (polar moment) is WR2 (radius squared).  That's why propellers make such good flywheels.    Sometimes too good.

                  At 10:03 PM 4/24/2013 +0000, you wrote:
                   

                  The high quality of the replies from you folk says everything; I aren't time-served as a machinist but a fitter, and didn't realise how much there was to an apparently simple task such as creating a taper.

                  The tip about cutter height being exactly level with centreline, to avoid a curved taper, hadn't hit until it was pointed out, thanks.

                  Thing is, the centre region of a flywheel is the least, and the rim the most useful, as radius of action times weight (OK mass, but I'm trying not to be an engineering snob) is the measure of effectiveness.

                  When you see a dirty great lump of iron on the crankshaft, it seemed to make sense to rip out the middle and swap it for alloy. Downside is the timing will need carefully setting up, but that looks easy enough with a clock gauge to find top dead centre, and some measurements taken from the stock wheel's magnet location, then bolt the rim onto a new alloy middle in the same relationship.

                  Maybe I should leave the flywheel alone now as the alloy ones aren't chap and lack generator magnets, unless the can be prised off and stuck into an alloy wheel. All that risk and expense looked just about viable, but if the taper is trickier than it looks maybe it is best to look elsewhere to lose weight.

                  Back to the drawing board...

                  Cheers

                  Kev

                  --- In Small4-strokeEngines@yahoogroups.com, ron ohler <ohler_ron@...> wrote:
                  >
                  > Hi,
                  > There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
                  > Â
                  > A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe
                  > will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
                  > If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
                  > Best,
                  > RonOÂ
                  > --- On Wed, 4/24/13, Peter Walker <peterwalker58@...> wrote:
                  >
                  >
                  > From: Peter Walker <peterwalker58@...>
                  > Subject: Re: [Small4-strokeEngines] flywheel butchering
                  > To: " Small4-strokeEngines@yahoogroups.com" < Small4-strokeEngines@yahoogroups.com>
                  > Date: Wednesday, April 24, 2013, 1:07 AM
                  >
                  >
                  >
                  >  
                  >
                  >
                  >
                  >
                  >
                  > Hello Ron
                  > Â I have not seen that one Can you explain it further
                  > Even on CNCs we used plug gauges as a setup and checking toolÂ
                  > Peter
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  > From: ron ohler <ohler_ron@...>
                  > To: Small4-strokeEngines@yahoogroups.com
                  > Sent: Wednesday, April 24, 2013 11:44 AM
                  > Subject: Re: [Small4-strokeEngines] flywheel butchering
                  >
                  >
                  >
                  >
                  >  
                  >
                  >
                  >
                  >
                  >
                  > Hi,
                  > turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
                  > Best,
                  > RonO
                  >
                  >
                  > --- On Tue, 4/23/13, Peter Walker <peterwalker58@...> wrote:
                  >
                  >
                  > From: Peter Walker <peterwalker58@...>
                  > Subject: Re: [Small4-strokeEngines] flywheel butchering
                  > To: " Small4-strokeEngines@yahoogroups.com" < Small4-strokeEngines@yahoogroups.com>
                  > Date: Tuesday, April 23, 2013, 10:43 PM
                  >
                  >
                  >
                  >  
                  >
                  >
                  >
                  > Hello George
                  > Â I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from thereÂ
                  > Peter
                  >
                  >
                  >
                  >
                  >
                  >
                  > From: George Bearden <gab16@...>
                  > To: Small4-strokeEngines@yahoogroups.com
                  > Sent: Wednesday, April 24, 2013 9:24 AM
                  > Subject: RE: [Small4-strokeEngines] flywheel butchering
                  >
                  >
                  >
                  >
                  >  
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  > > A good shop will turn a taper plug to match your flywheel
                  > Â
                  > I'm glad you smart people are on here!
                  > Â
                  >

                • Peter Walker
                  Hello The problem is an unknown taper in an existing flywheel The tapered plug is a way to set a lathe to make a taper to match using the flywheel The rest was
                  Message 8 of 22 , Apr 25, 2013
                  • 0 Attachment
                    Hello
                    The problem is an unknown taper in an existing flywheel
                    The tapered plug is a way to set a lathe to make a taper to match using the flywheel
                    The rest was a technical way to set a lathe to high precision in the taper was known
                    Peter


                    From: gypsyinvader <garrywarber@...>
                    To: Small4-strokeEngines@yahoogroups.com
                    Sent: Friday, April 26, 2013 2:48 AM
                    Subject: [Small4-strokeEngines] Re: flywheel butchering

                     
                    This thread's point is very confusing. I think a flywheel is having a new center of aluminum made for the old magnet-holding rim? If so, why are you guys talking of machining the crankshaft when you should be machining a taper reamer to ream the new alloy wheel center disk to match the crankshaft's taper?

                    --- In Small4-strokeEngines@yahoogroups.com, "Kev A" <kevin@...> wrote:
                    >
                    > The high quality of the replies from you folk says everything; I aren't time-served as a machinist but a fitter, and didn't realise how much there was to an apparently simple task such as creating a taper.
                    >
                    > The tip about cutter height being exactly level with centreline, to avoid a curved taper, hadn't hit until it was pointed out, thanks.
                    >
                    > Thing is, the centre region of a flywheel is the least, and the rim the most useful, as radius of action times weight (OK mass, but I'm trying not to be an engineering snob) is the measure of effectiveness.
                    >
                    > When you see a dirty great lump of iron on the crankshaft, it seemed to make sense to rip out the middle and swap it for alloy. Downside is the timing will need carefully setting up, but that looks easy enough with a clock gauge to find top dead centre, and some measurements taken from the stock wheel's magnet location, then bolt the rim onto a new alloy middle in the same relationship.
                    >
                    > Maybe I should leave the flywheel alone now as the alloy ones aren't chap and lack generator magnets, unless the can be prised off and stuck into an alloy wheel. All that risk and expense looked just about viable, but if the taper is trickier than it looks maybe it is best to look elsewhere to lose weight.
                    >
                    > Back to the drawing board...
                    >
                    > Cheers
                    >
                    > Kev
                    >
                    > --- In Small4-strokeEngines@yahoogroups.com, ron ohler <ohler_ron@> wrote:
                    > >
                    > > Hi,
                    > > There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
                    > >  
                    > > A test bar is typically a straight ground bar with centers in the end. They are normally used for calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar is set up in the lathe. The machinist sets up a travel indicator on the compound to read length(or z axis) off of a flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate) and other one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled until the desired amount reads on the Z axis  -  I like to use at least 1" - and the reading of the other indicator is observed. Simple geometry for right triangles will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe
                    > > will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
                    > > If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted. If it is easier you can also face the test bar for reading the X axis from. For chucked work, reading off of a freshly turned part would ensure that the reading is taken from the actual spindle centerline.
                    > > Best,
                    > > RonO 
                    > > --- On Wed, 4/24/13, Peter Walker <peterwalker58@> wrote:
                    > >
                    > >
                    > > From: Peter Walker <peterwalker58@>
                    > > Subject: Re: [Small4-strokeEngines] flywheel butchering
                    > > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                    > > Date: Wednesday, April 24, 2013, 1:07 AM
                    > >
                    > >
                    > >
                    > >  
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > Hello Ron
                    > >  I have not seen that one Can you explain it further
                    > > Even on CNCs we used plug gauges as a setup and checking tool 
                    > > Peter
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > From: ron ohler <ohler_ron@>
                    > > To: Small4-strokeEngines@yahoogroups.com
                    > > Sent: Wednesday, April 24, 2013 11:44 AM
                    > > Subject: Re: [Small4-strokeEngines] flywheel butchering
                    > >
                    > >
                    > >
                    > >
                    > >  
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > Hi,
                    > > turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
                    > > Best,
                    > > RonO
                    > >
                    > >
                    > > --- On Tue, 4/23/13, Peter Walker <peterwalker58@> wrote:
                    > >
                    > >
                    > > From: Peter Walker <peterwalker58@>
                    > > Subject: Re: [Small4-strokeEngines] flywheel butchering
                    > > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                    > > Date: Tuesday, April 23, 2013, 10:43 PM
                    > >
                    > >
                    > >
                    > >  
                    > >
                    > >
                    > >
                    > > Hello George
                    > >  I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there 
                    > > Peter
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > From: George Bearden <gab16@>
                    > > To: Small4-strokeEngines@yahoogroups.com
                    > > Sent: Wednesday, April 24, 2013 9:24 AM
                    > > Subject: RE: [Small4-strokeEngines] flywheel butchering
                    > >
                    > >
                    > >
                    > >
                    > >  
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > > A good shop will turn a taper plug to match your flywheel
                    > >  
                    > > I'm glad you smart people are on here!
                    > >  
                    > >
                    >



                  • mirco@jps.net
                    I think you can buy a steel hub that already has the taper machined in. www.arcracing.com They make Aluminum Flywheels and I think sell the hubs also. Give
                    Message 9 of 22 , Apr 25, 2013
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                      I think you can buy a steel hub that already has the taper machined in.  www.arcracing.com   They make Aluminum Flywheels and I think sell the hubs also.  Give them a call.
                       
                      Murry I. Rozansky
                       
                       
                       
                      ----- Original Message -----
                      Sent: 4/25/2013 2:55:01 PM
                      Subject: Re: [Small4-strokeEngines] Re: flywheel butchering

                       

                      Hello
                      The problem is an unknown taper in an existing flywheel
                      The tapered plug is a way to set a lathe to make a taper to match using the flywheel
                      The rest was a technical way to set a lathe to high precision in the taper was known
                      Peter


                      From: gypsyinvader <garrywarber@...>
                      To: Small4-strokeEngines@yahoogroups.com
                      Sent: Friday, April 26, 2013 2:48 AM
                      Subject: [Small4-strokeEngines] Re: flywheel butchering

                       
                      This thread's point is very confusing. I think a flywheel is having a new center of aluminum made for the old magnet-holding rim? If so, why are you guys talking of machining the crankshaft when you should be machining a taper reamer to ream the new alloy wheel center disk to match the crankshaft's taper?

                      --- In Small4-strokeEngines@yahoogroups.com, "Kev A" <kevin@...> wrote:
                      >
                      > The high quality of the replies from you folk says everything; I aren't time-served as a machinist but a fitter, and didn't realise how much there was to an apparently simple task such as creating a taper.
                      >
                      > The tip about cutter height being exactly level with centreline, to avoid a curved taper, hadn't hit until it was pointed out, thanks.
                      >
                      > Thing is, the centre region of a flywheel is the least, and the rim the most useful, as radius of action times weight (OK mass, but I'm trying not to be an engineering snob) is the measure of effectiveness.
                      >
                      > When you see a dirty great lump of iron on the crankshaft, it seemed to make sense to rip out the middle and swap it for alloy. Downside is the timing will need carefully setting up, but that looks easy enough with a clock gauge to find top dead centre, and some measurements taken from the stock wheel's magnet location, then bolt the rim onto a new alloy middle in the same relationship.
                      >
                      > Maybe I should leave the flywheel alone now as the alloy ones aren't chap and lack generator magnets, unless the can be prised off and stuck into an alloy wheel. All that risk and expense looked just about viable, but if the taper is trickier than it looks maybe it is best to look elsewhere to lose weight.
                      >
                      > Back to the drawing board...
                      >
                      > Cheers
                      >
                      > Kev
                      >
                      > --- In Small4-strokeEngines@yahoogroups.com, ron ohler <ohler_ron@> wrote:
                      > >
                      > > Hi,
                      > > There are videos on the net that probably would help understand if I fail to describe this sufficiently to be understood. A simple review of solutions for right triangles should remind you of how a triangle made up of 2 legs at right angles (X and Z axis) can easily have an angle determined when the length of 2 legs is known.
                      > > �� 
                      > > A test bar is typically a straight ground bar with centers in the end.�� They are normally used for�� calibrating the tailstock location. A mandrel can be used if the machinist can handle the math needed to correct for the taper in the mandrel(sarcasm). The test bar�� is set up in the lathe.�� The machinist sets up a travel indicator�� on the compound to read length(or z axis) off of a�� flat and perpendicular surface tot he test bar(spindle face, chuck face(if accurate)�� and other�� one on the compound measures distance from the test bar. I like to use a 2" travel indicator for the Z axis. Both indicators are set to zero. Then the compound is traveled�� until the desired amount reads on the Z axis �� -��  I�� like to use at least�� 1" - and the reading of the other indicator is observed. Simple geometry for right triangles�� will tell you what (I'll call it the x direction indicator) should indicate. This measurement does need to be 1/2 that desired as the lathe
                      > > will double the angle when the part is tuned. If you're using a tapered mandrel you have to figure 1/2 of the taper in the mandrel also.
                      > > If you don't have a test bar then a bar can be turned for a short length to get a usable surface and this freshly turned surface should be accurate. This is�� what should be done if the part is only to be chucked and not run between centers as the tailstock could produce an offset in a test bar that would not be noted.�� If it is easier you can also face the test bar for reading the X axis from. For chucked work,�� reading off of a freshly�� turned part would ensure that the reading is taken from the actual spindle�� centerline.
                      > > Best,
                      > > RonO�� 
                      > > --- On Wed, 4/24/13, Peter Walker <peterwalker58@> wrote:
                      > >
                      > >
                      > > From: Peter Walker <peterwalker58@>
                      > > Subject: Re: [Small4-strokeEngines] flywheel butchering
                      > > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                      > > Date: Wednesday, April 24, 2013, 1:07 AM
                      > >
                      > >
                      > >
                      > > �� 
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > Hello Ron
                      > > �� I have not seen that one Can you explain it further
                      > > Even on CNCs we used plug gauges as a setup and checking tool�� 
                      > > Peter
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > From: ron ohler <ohler_ron@>
                      > > To: Small4-strokeEngines@yahoogroups.com
                      > > Sent: Wednesday, April 24, 2013 11:44 AM
                      > > Subject: Re: [Small4-strokeEngines] flywheel butchering
                      > >
                      > >
                      > >
                      > >
                      > > �� 
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > Hi,
                      > > turning a plug and getting the angle perfect is a guess and by golly method. It is time consuming and rarely as accurate as it should be. A test bar and 2 indicators is far more accurate and faster.
                      > > Best,
                      > > RonO
                      > >
                      > >
                      > > --- On Tue, 4/23/13, Peter Walker <peterwalker58@> wrote:
                      > >
                      > >
                      > > From: Peter Walker <peterwalker58@>
                      > > Subject: Re: [Small4-strokeEngines] flywheel butchering
                      > > To: "Small4-strokeEngines@yahoogroups.com" <Small4-strokeEngines@yahoogroups.com>
                      > > Date: Tuesday, April 23, 2013, 10:43 PM
                      > >
                      > >
                      > >
                      > > �� 
                      > >
                      > >
                      > >
                      > > Hello George
                      > > �� I stuffed up A good shop wouldn't even ask what the tapers is They would just turn the plug and go from there�� 
                      > > Peter
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > From: George Bearden <gab16@>
                      > > To: Small4-strokeEngines@yahoogroups.com
                      > > Sent: Wednesday, April 24, 2013 9:24 AM
                      > > Subject: RE: [Small4-strokeEngines] flywheel butchering
                      > >
                      > >
                      > >
                      > >
                      > > �� 
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > > A good shop will turn a taper plug to match your flywheel
                      > > �� 
                      > > I'm glad you smart people are on here!
                      > > �� 
                      > >
                      >



                    • Gary Gower
                      Hello Friends, Well, lots of time has passed since my last post...  I have been working as much as I can in my 3 main projects:    My retirement
                      Message 10 of 22 , May 16, 2013
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                        Hello Friends,

                        Well, lots of time has passed since my last post...  I have been working as much as I can in my 3 "main" projects:   

                        My retirement paperwork (done!),  my Flying Flea cabin (done!)  and finishing the few mods to my Spoon converted Generac engine  to work well in my Flea (intake, carburetor, headers and installing the little Kubota generator, etc  including all the side work that goes with this "last minute" details)...  

                        Also had some personal "time consuming" things to do that were getting in the way, like my everyday work, family (including my first granddaughter), a couple of  motorcycle trips and some bicycle tours...

                        Now I  am in the process of calculate and carve the propeller....  So I will like to hear some comments/advise  from  pilots flying with this engine...  

                        I will like to know the rpm's where the engine works smooth (better) in cruise, so I can estimate my first  pitch cut for the propeller,  that will be a good start... 

                        I think I will need to carve two or maybe 3 props to eventually get to the best one...   A common practice here for a new airplane/engine combo, given our aerodrome altitude over sea level  (5,000 ft ASL) and outside air temperature...

                        Yes, I will post some new photos as soon as possible, a few every night I think. Just got from my daughter the correct converter for my camera memory/ to my computer... Now (I think) I will be able to unload the photos to the hard drive, make a selection and upload them to the photo page...

                        Thank you all very much and will keep posting...

                        Gary Gower
                        Flying from Chapala, Mexico
                        Pouchel  "La Bamba" ladder Flea, now with a 447 for the few first flights with the cabin.
                        PS:    Spoon my friend,  Thank you very very  much, one more time for the great work done to this  engine, I thought that was going the be faster to have it installed and flying.....   This is homebuilding  time... 
                        "We know when we start, but will never know in advance when the project will be finished".
                      • warren
                        I have no idea what machine shop time costs, but maybe the easiest, and possibly therefore cheapest, would be to buy an alloy hub (or complete alloy flywheel)
                        Message 11 of 22 , May 24, 2013
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                          I have no idea what machine shop time costs, but maybe the easiest, and possibly therefore cheapest, would be to buy an alloy hub (or complete alloy flywheel) from the folks who sell the racing parts - they obviously have the taper issue figured out. Then use that hub with your cast flywheel rim.

                          Maybe the machinist can cut the center out of the cast flywheel without needing to machine a tapered arbor for it. :-)

                          Just be sure the alloy web between the hub and rim is strong enough to stand the precession forces - I have no idea how to calculate that, but you don't want the two separating. I recall that the auto conversion guys had problems with that when they tried using auto trans flex plates to support the starter ring gears with less weight than the manual trans flywheels. Turns out even the relatively lightweight ring gear still caused enough stress to crack the flex plates - apparently the flex a lot when not bolted to a torque converter as they are in a standard car installation.

                          Warren

                          -
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