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Lathe Beds: Re: OT:anyone have a hankering to build a Romig style lathe?

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  • charcad2006
    Chris, The main problem with concrete as the outer structure is one needs an accurate replication surface to cast it on to get a flat bed for mounting the
    Message 1 of 34 , Aug 3, 2009
    • 0 Attachment
      Chris,

      The main problem with concrete as the outer structure is one needs an accurate replication surface to cast it on to get a flat bed for mounting the ways. A granite surface plate or homebrew equivalent. Errors in the bed will be reflected in the steel ways. In your case of ground flat stock it would distort it once it's bolted down. Now your handscraping job is in steel, not aluminum. Even though you paid much more for ground flat stock than CRS costs.

      Structural epoxy granite, as opposed to a vibration dampening filler, still isn't ready for prime time at the home shop level. Some quite knowledgeable engineers have been working on this for several years in the CNC Zone EPG thread and in their labs. They still don't have it reduced to home shop level.

      Concrete & EPG filled lathe bed alternatives:

      1. Steel Tube

      In my area Alro Metals in Sarasota Florida has a very large remnants section. Almost the size of the "prime stock" area. Steel tube costs 85 cents/lb. 3"x3"x.375" wall square tube weighs 1.05 lbs/inch. A 24" length for a lathe bed carrying 4" to 5" wide ways would run $21, plus a $5 cut fee if the stock was longer.

      Then have this tube milled flat on top/bottom. If you don't know anyone with a mill then do it at a local machine shop. This is a very basic milling job. Either a general shop or an engine rebuild shop. If you talk to owner/managers you can often get a very good rate - down to "free" - once they know you aren't a commercial cu$tomer. Often they'll give it to one of their machinists who'll do it after hours as a private side job.

      2. T-slot aluminum extrusion bed. ("80/20")

      With this product you already start with a surface flatness good to hundreths. Much easier hand scraping job than a cast Al Gingery bed.

      No reason t-slot extrusion can't be filled with EP/G for vibration dampening. Also no reason one can't suspend lengths of 1/2" or 5/8" rebar inside the hollow extrusion profile before pouring in EP/G.

      Strength comparison. The yield strength of cast gray iron ranges from 20,000 to 60,000 psi. T-slot aluminum extrusion has a minimum yield strength of 30,000 psi. i.e. right in the ballpark of the Harbor Freight/Enco/Grizzly grade of import lathe beds. And this is before hand-tying rebar inside the hollow 8020 profile to raise this strength.

      Never been a better time to buy, either. The bottom has fallen out of the eBay 8020 drops market.

      http://cgi.ebay.com/8020-T-Slot-Aluminum-Extrusion-15-S-3030-Lot-7-3pcs_W0QQitemZ370237677131QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5633e29e4b&_trksid=p3286.c0.m14

      $56 including shipping for three pieces of 3" x 3", 23" to 27". 8020's old industrial customers are now competing in the after- market as they liquidate shop stock and production lines.

      Meanwhile cast A356 aluminum alloy has a yield strength 24,000 psi. This is the upper strength one is likely to achieve in the DIY foundry. Assuming you only use salvaged engine pistons and otherwise follow excellent casting practice. Subtract for sand inclusions, hydrogen porosity, brittle fractures, FeO contamination of the melt from steel pipe crucible scaling, etc.

      Truth is the as-cast Gingery lathe and mill beds are comparable to reinforced concrete in yield strength.




      --- In multimachine@yahoogroups.com, Chris M <chrism3667@...> wrote:
      >
      > Bruce, this is mainly a fun exercise. I'd build a Gingery style lathe, but it's a bit light. Roller bearings are cheap enough (4" bore??!! Icarumba! I'd be too happy if I could push a 1" shaft through the spindle).
      >  Anyway, I started a yahoo group probably 3 years ago for this and other purposes (the idea has got my goat a longer time ago then that). In deference to our valiant leader, I won't advertise it here, not that it would detract from this discussion one bit (no messages posted in months). I'm sure you'll agree, the idea of building a lathe, or a blasted vertical mill, is too tantalizing. There have been a number of ideas floating around out there for, well centuries basically. The Romig design is compact. I had the opportunity to bring home a drop dead gorgeous lathe a number of years ago, 18" swing IIRC, for free. Fumbled that one. So nothing against larger lathes. There's just a special place in my heart for smaller units.
      >  Oh by the way, I already own about 18 lathes in various states of completeness. It's not that I NEED to build one, but as I said, I find the idea of doing so fascinating.
      >  What would I do with it? Make chips LOLOLOLOLOLOLOLOLOL. What did you think I would want it fer?
      >
      > --- On Sun, 8/2/09, Bruce Bellows <bbellows@...> wrote:
      >
      > From: Bruce Bellows <bbellows@...>
      > Subject: Re: [multimachine] Re: OT:anyone have a hankering to build a Romig style lathe?
      > To: multimachine@yahoogroups.com
      > Date: Sunday, August 2, 2009, 1:04 PM
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      > Hi Chris
      >  
      > I think the first step in building a lathe is probably the
      > cheapest and that's defining what you want your lathe to do and be for you. If
      > you just want to make round objects it can be cheap and easy, if you want to
      > make highly precise round objects the cost can go up accordingly. As an
      > example a standard class tapered roller bearing with a 4" bore can be bought for
      > approx. $60.00 The same bearing as a precision class 3, which is most common in
      > a standard lathe, goes for about $400.00 
      >  
      > So first decide what you want your lathe to be for
      > you.
      > There are a multitude of approaches you can take
      >  
      > Lathe Beds made from
      > An engine block
      > Cast Iron
      > Cast Epoxy Granite
      > EG filled rect steel tube
      > Aluminium
      >  
      > Ways
      > Linear guide rails
      > Ground cast iron
      > dovetailed tool steel
      >  
      > Hope this gives you a few ideas to ponder. Thinking it through
      > first will save you a lot of money later.
      >  
      > Bruce
      >  
      >
      > ----- Original Message -----
      > From:
      > keith
      > gutshall
      > To: multimachine@yahoogroups.com
      >
      > Sent: Sunday, August 02, 2009 12:30
      > AM
      > Subject: Re: [multimachine] Re: OT:anyone
      > have a hankering to build a Romig style lathe?
      >
      >  
      >
      >
      >
      >
      >
      >
      > Hello Chris M
      >  Building a lathe is not a inexpenive as you may think.
      >  A good 6in chuck is about $100
      >  A 1/2 HP motor is $125+ for them.
      >  
      >  The 8 in 2 groove pulley I got was $75  for it. It is on
      > the spindle.
      >  
      >  A piece of ground stock 1/2x4x36 can be as high as $200+ for
      > it.
      >  
      >  I have invested $750-800 in the machine I am building, and
      > have not started to
      >  build the ways and carriage yet. I got the 6 cylinder block
      > for $0.
      >  
      >  Cold rolled steel is good for ways for the price of it. I am
      > going to useit
      >  for the ways on the machine I am building.
      >  
      >  Keith G
      >
      > Deep Run Portage
      > Back Shop
      > " The Lizard
      > Works"
      >
      > --- On Sat, 8/1/09, Chris M
      > <chrism3667@yahoo. com> wrote:
      >
      >
      > From:
      > Chris M <chrism3667@yahoo. com>
      > Subject: Re:
      > [multimachine] Re: OT:anyone have a hankering to build a Romig style
      > lathe?
      > To: multimachine@ yahoogroups. com
      > Date:
      > Saturday, August 1, 2009, 8:30 PM
      >
      >
      >  
      >
      >
      > you've always been a gentleman Pat.
      >
      > Now others just
      > need to share the interest :)
      >
      > In all reality, it would probably
      > cost the better part of 200$ to build one, since I'd be using
      > precision ground steel for the ways and slides. Might be able to get
      > by w/CRS for the support pieces. Maybe less considerably, I don't
      > know.
      >
      > *sits and waits*
      >
      > --- On Sat, 8/1/09, Pat Delany
      > <rigmatch@yahoo. com>
      > wrote:
      >
      > > From: Pat Delany <rigmatch@yahoo.
      > com>
      > > Subject: [multimachine] Re: OT:anyone have a
      > hankering to build a Romig style lathe?
      > > To: multimachine@
      > yahoogroups. com
      > > Date: Saturday, August 1, 2009, 9:13
      > PM
      > > Great with me. Just take a lot of
      > > pics for
      > us.
      > >
      > > Pat
      > >
      > > --- In multimachine@
      > yahoogroups. com,
      > > Chris M <chrism3667@ ...>
      > wrote:
      > > >
      > > > I'm interested in building one of
      > these. If anyone
      > > else wants to (and apologies to the
      > moderator), drop me a
      > > line or respond (as long as the mod
      > doesn't mind) on the
      > > list. We could even get a side discussion
      > going (again if
      > > the mod doesn't object). It's what the doctor
      > ordered it
      > > would seem if you want an actual bench lathe. I
      > think it
      > > would be fun. Carry on otherwise maties!
      > >
      > >
      > >
      > >
      > >
      > >
      > > ------------
      > --------- --------- ------
      > >
      > > Yahoo! Groups
      > Links
      > >
      > >
      > > mailto:multimachine-
      > fullfeatured@ yahoogroups. com
      > >
      > >
      > >
      >
    • Bruce Bellows
      8020 is the name of the manufacturer of extruded aluminium profiles that have built in T slots. Here is their web site. http://www.8020.net/Default.asp The
      Message 34 of 34 , Aug 13, 2009
      • 0 Attachment
        8020 is the name of the manufacturer of extruded aluminium profiles that have built in T slots. Here is their web site.
         
        The same type of product is also made by Bosch, Item and a few others that don't come to mind right now. Great stuff for building all kinds of different frame based products. I've found the aluminium bars to be reasonably priced but the fittings for joining them to be a bit pricey.
         
        Bruce
         
        ----- Original Message -----
        Sent: Thursday, August 13, 2009 9:45 PM
        Subject: Re: [multimachine] Lathe Beds: Re: OT:anyone have a hankering to build a Romig style lathe?

         

        Mark,
         
        Pardon my ignorance but the term 8020 is unfamiliar to me. Could you elaborate on what it is? Thank you.
         
        ... Gus
        ----- Original Message -----
        Sent: Thursday, August 13, 2009 5:46 PM
        Subject: [multimachine] Lathe Beds: Re: OT:anyone have a hankering to build a Romig style lathe?

         

        Bruce,

        I saw some of the German projects earlier, including that one. Nice machine.

        It's more a fact than a problem, but a certain amount of ancillary equipment is needed for that level of work. Granite surface plates, vibrator tables or match plate vibrators to compact the aggregate in the mold, vacuum pots or chambers to de-air the epoxy right before pouring...

        I will concede close to a comparable level of equipment for hot metal casting.

        I'm a lot more interested in composite steel & EPG for headstocks, tailstocks and similar parts.

        A big reason I like 8020 is the ability to hand scrape long lengths of 8020 dead flat using the Rule of Threes, and without having a massive surface plate or other precision test standard surface. That is, just start with three pieces of 8020 of equal length.

        This rule of threes trick can be repeated after mounting CRS flats on the 8020.

        Something you might consider in the context of split ways of, say, 60" length. Or longer. Surface plates of that length are going to be expensive even if somebody gives you one FOB. Transportation costs.

        Mark


        --- In multimachine@ yahoogroups. com, "Bruce Bellows" <bbellows@.. .> wrote:
        >
        > Mark
        >
        > Here is the link to the epoxy granite machine base that we recently discussed . It's located in the files/polyconcrete folder
        >
        > http://f1.grp. yahoofs.com/ v1/8LmDSr1L9i10d If6RnMDOeQpYWxo9 N4HwNz6G2_ PNlvZx6ZZ9nsKtvL rp5jVC-7UxAFJPo2 OPVLU_kTtbsUwPda ZiVtxoDLOYC12/ %28Poly%29Concre te%20Uses% 20in%20Machine/ German%20Epoxy% 20Granite% 20Milling% 20Machine. pdf
        >
        > Bruce
        >
        > ----- Original Message -----
        > From: charcad2006
        > To: multimachine@ yahoogroups. com
        > Sent: Monday, August 03, 2009 2:43 PM
        > Subject: [multimachine] Lathe Beds: Re: OT:anyone have a hankering to build a Romig style lathe?
        >
        >
        > Chris,
        >
        > The main problem with concrete as the outer structure is one needs an accurate replication surface to cast it on to get a flat bed for mounting the ways. A granite surface plate or homebrew equivalent. Errors in the bed will be reflected in the steel ways. In your case of ground flat stock it would distort it once it's bolted down. Now your handscraping job is in steel, not aluminum. Even though you paid much more for ground flat stock than CRS costs.
        >
        > Structural epoxy granite, as opposed to a vibration dampening filler, still isn't ready for prime time at the home shop level. Some quite knowledgeable engineers have been working on this for several years in the CNC Zone EPG thread and in their labs. They still don't have it reduced to home shop level.
        >
        > Concrete & EPG filled lathe bed alternatives:
        >
        > 1. Steel Tube
        >
        > In my area Alro Metals in Sarasota Florida has a very large remnants section. Almost the size of the "prime stock" area. Steel tube costs 85 cents/lb. 3"x3"x.375" wall square tube weighs 1.05 lbs/inch. A 24" length for a lathe bed carrying 4" to 5" wide ways would run $21, plus a $5 cut fee if the stock was longer.
        >
        > Then have this tube milled flat on top/bottom. If you don't know anyone with a mill then do it at a local machine shop. This is a very basic milling job. Either a general shop or an engine rebuild shop. If you talk to owner/managers you can often get a very good rate - down to "free" - once they know you aren't a commercial cu$tomer. Often they'll give it to one of their machinists who'll do it after hours as a private side job.
        >
        > 2. T-slot aluminum extrusion bed. ("80/20")
        >
        > With this product you already start with a surface flatness good to hundreths. Much easier hand scraping job than a cast Al Gingery bed.
        >
        > No reason t-slot extrusion can't be filled with EP/G for vibration dampening. Also no reason one can't suspend lengths of 1/2" or 5/8" rebar inside the hollow extrusion profile before pouring in EP/G.
        >
        > Strength comparison. The yield strength of cast gray iron ranges from 20,000 to 60,000 psi. T-slot aluminum extrusion has a minimum yield strength of 30,000 psi. i.e. right in the ballpark of the Harbor Freight/Enco/ Grizzly grade of import lathe beds. And this is before hand-tying rebar inside the hollow 8020 profile to raise this strength.
        >
        > Never been a better time to buy, either. The bottom has fallen out of the eBay 8020 drops market.
        >
        > http://cgi.ebay. com/8020- T-Slot-Aluminum- Extrusion- 15-S-3030- Lot-7-3pcs_ W0QQitemZ3702376 77131QQcmdZViewI temQQptZLH_ DefaultDomain_ 0?hash=item5633e 29e4b&_trksid= p3286.c0. m14
        >
        > $56 including shipping for three pieces of 3" x 3", 23" to 27". 8020's old industrial customers are now competing in the after- market as they liquidate shop stock and production lines.
        >
        > Meanwhile cast A356 aluminum alloy has a yield strength 24,000 psi. This is the upper strength one is likely to achieve in the DIY foundry. Assuming you only use salvaged engine pistons and otherwise follow excellent casting practice. Subtract for sand inclusions, hydrogen porosity, brittle fractures, FeO contamination of the melt from steel pipe crucible scaling, etc.
        >
        > Truth is the as-cast Gingery lathe and mill beds are comparable to reinforced concrete in yield strength.
        >
        > --- In multimachine@ yahoogroups. com, Chris M <chrism3667@ > wrote:
        > >
        > > Bruce, this is mainly a fun exercise. I'd build a Gingery style lathe, but it's a bit light. Roller bearings are cheap enough (4" bore??!! Icarumba! I'd be too happy if I could push a 1" shaft through the spindle).
        > > Anyway, I started a yahoo group probably 3 years ago for this and other purposes (the idea has got my goat a longer time ago then that). In deference to our valiant leader, I won't advertise it here, not that it would detract from this discussion one bit (no messages posted in months). I'm sure you'll agree, the idea of building a lathe, or a blasted vertical mill, is too tantalizing. There have been a number of ideas floating around out there for, well centuries basically. The Romig design is compact. I had the opportunity to bring home a drop dead gorgeous lathe a number of years ago, 18" swing IIRC, for free. Fumbled that one. So nothing against larger lathes. There's just a special place in my heart for smaller units.
        > > Oh by the way, I already own about 18 lathes in various states of completeness. It's not that I NEED to build one, but as I said, I find the idea of doing so fascinating.
        > > What would I do with it? Make chips LOLOLOLOLOLOLOLOLOL . What did you think I would want it fer?
        > >
        > > --- On Sun, 8/2/09, Bruce Bellows <bbellows@> wrote:
        > >
        > > From: Bruce Bellows <bbellows@>
        > > Subject: Re: [multimachine] Re: OT:anyone have a hankering to build a Romig style lathe?
        > > To: multimachine@ yahoogroups. com
        > > Date: Sunday, August 2, 2009, 1:04 PM
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > > Hi Chris
        > >
        > > I think the first step in building a lathe is probably the
        > > cheapest and that's defining what you want your lathe to do and be for you. If
        > > you just want to make round objects it can be cheap and easy, if you want to
        > > make highly precise round objects the cost can go up accordingly. As an
        > > example a standard class tapered roller bearing with a 4" bore can be bought for
        > > approx. $60.00 The same bearing as a precision class 3, which is most common in
        > > a standard lathe, goes for about $400.00
        > >
        > > So first decide what you want your lathe to be for
        > > you.
        > > There are a multitude of approaches you can take
        > >
        > > Lathe Beds made from
        > > An engine block
        > > Cast Iron
        > > Cast Epoxy Granite
        > > EG filled rect steel tube
        > > Aluminium
        > >
        > > Ways
        > > Linear guide rails
        > > Ground cast iron
        > > dovetailed tool steel
        > >
        > > Hope this gives you a few ideas to ponder. Thinking it through
        > > first will save you a lot of money later.
        > >
        > > Bruce
        > >
        > >
        > > ----- Original Message -----
        > > From:
        > > keith
        > > gutshall
        > > To: multimachine@ yahoogroups. com
        > >
        > > Sent: Sunday, August 02, 2009 12:30
        > > AM
        > > Subject: Re: [multimachine] Re: OT:anyone
        > > have a hankering to build a Romig style lathe?
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > > Hello Chris M
        > > Building a lathe is not a inexpenive as you may think.
        > > A good 6in chuck is about $100
        > > A 1/2 HP motor is $125+ for them.
        > >
        > > The 8 in 2 groove pulley I got was $75 for it. It is on
        > > the spindle.
        > >
        > > A piece of ground stock 1/2x4x36 can be as high as $200+ for
        > > it.
        > >
        > > I have invested $750-800 in the machine I am building, and
        > > have not started to
        > > build the ways and carriage yet. I got the 6 cylinder block
        > > for $0.
        > >
        > > Cold rolled steel is good for ways for the price of it. I am
        > > going to useit
        > > for the ways on the machine I am building.
        > >
        > > Keith G
        > >
        > > Deep Run Portage
        > > Back Shop
        > > " The Lizard
        > > Works"
        > >
        > > --- On Sat, 8/1/09, Chris M
        > > <chrism3667@ yahoo. com> wrote:
        > >
        > >
        > > From:
        > > Chris M <chrism3667@ yahoo. com>
        > > Subject: Re:
        > > [multimachine] Re: OT:anyone have a hankering to build a Romig style
        > > lathe?
        > > To: multimachine@ yahoogroups. com
        > > Date:
        > > Saturday, August 1, 2009, 8:30 PM
        > >
        > >
        > >
        > >
        > >
        > > you've always been a gentleman Pat.
        > >
        > > Now others just
        > > need to share the interest :)
        > >
        > > In all reality, it would probably
        > > cost the better part of 200$ to build one, since I'd be using
        > > precision ground steel for the ways and slides. Might be able to get
        > > by w/CRS for the support pieces. Maybe less considerably, I don't
        > > know.
        > >
        > > *sits and waits*
        > >
        > > --- On Sat, 8/1/09, Pat Delany
        > > <rigmatch@yahoo. com>
        > > wrote:
        > >
        > > > From: Pat Delany <rigmatch@yahoo.
        > > com>
        > > > Subject: [multimachine] Re: OT:anyone have a
        > > hankering to build a Romig style lathe?
        > > > To: multimachine@
        > > yahoogroups. com
        > > > Date: Saturday, August 1, 2009, 9:13
        > > PM
        > > > Great with me. Just take a lot of
        > > > pics for
        > > us.
        > > >
        > > > Pat
        > > >
        > > > --- In multimachine@
        > > yahoogroups. com,
        > > > Chris M <chrism3667@ ...>
        > > wrote:
        > > > >
        > > > > I'm interested in building one of
        > > these. If anyone
        > > > else wants to (and apologies to the
        > > moderator), drop me a
        > > > line or respond (as long as the mod
        > > doesn't mind) on the
        > > > list. We could even get a side discussion
        > > going (again if
        > > > the mod doesn't object). It's what the doctor
        > > ordered it
        > > > would seem if you want an actual bench lathe. I
        > > think it
        > > > would be fun. Carry on otherwise maties!
        > > >
        > > >
        > > >
        > > >
        > > >
        > > >
        > > > ------------
        > > --------- --------- ------
        > > >
        > > > Yahoo! Groups
        > > Links
        > > >
        > > >
        > > > mailto:multimachine -
        > > fullfeatured@ yahoogroups. com
        > > >
        > > >
        > > >
        > >
        >

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