Loading ...
Sorry, an error occurred while loading the content.
 

Re: Belt drive

Expand Messages
  • robrohdeszudy
    And where do you find an air powered starter?! Thankee, --Rob ... from ... head). ... to ... keel ... drive ... To ... contact ... depression ... also ...
    Message 1 of 6 , Aug 26, 2005
      And where do you find an air powered starter?!
      Thankee,
      --Rob

      --- In AtkinBoats@yahoogroups.com, "oldbingey" <bingey@r...> wrote:
      > Dear Rob,
      >
      >
      > I appreciate your compliments and know who you are so that makes
      > them have some real significance.
      >
      > I'll answer those questions real quick because I am fixing to head
      > back to the coast to batten down for this next damned hurricane.
      >
      > 1. I turned the phenolic disc from a piece of 12"x12"x1" sheet
      from
      > McMaster Carr. I don't remember what it cost but it wasn't too
      > much and I was able to make some replacement sheaves out of the
      > scraps. The rubber tire that contacted it to give reverse was the
      > transmission drive wheel out of a Snapper riding lawn mower... $10.
      >
      > 2. The air spring is a miniature of the air springs on a semi
      > truck and is called an "air spring" in McMaster Carr.
      >
      > 3. The single drive belt is a sixteen groove belt about as big
      > around as my hat band (and some say I have a case of the big
      head).
      > The brand name is "PolyVee."
      >
      > 4. The thrust bearing is a regular farm duty flange block with a
      > one inch ID ball bearing. Both it and the belt have run for more
      > than 2,500 hours so far.
      >
      > It is a good transmission. I'll list some of the advantages:
      >
      > 1. It is much lighter than even a Hurth.
      >
      > 2. It runs almost without friction... no heat build up... no
      > transmission oil cooler.
      >
      > 3. The shaft runs in its own bearings attached in rigid alignment
      > to the hull of the boat and does not wiggle with the engine so the
      > stuffing box stays adjusted and does not leak at all. I assume the
      > cutless bearings will last longer, too.
      >
      > 4. It is cheap.
      >
      > 5. It runs quiet (silent).
      >
      > 6. It works on an engine without a heavy bellhousing... an
      > automotive engine without any "marine" adaptations.
      >
      > I have figured out how to put the air spring back on there so that
      > it won't rattle around but I have to take the boat out of service
      to
      > do the modifications and I can't do that right now. It runs almost
      > every day. I'll write up the details in MAIB to the point of
      > exhaustion.
      >
      > I also like that Normand stern on Shoals Runner. I don't know which
      > would be the better boat but I assume that there is a progression
      > and Shoals Runner was designed later.
      >
      > I don't know anything about chine style boats so I can't comment
      > about the difference in the chine angle of the two boats.
      >
      > My boat is way lighter than the Atkin boat.
      >
      > I am looking forward to reading about your project in "Duckworks."
      >
      > Good luck,
      >
      > Robb White.
      >
      > --- In AtkinBoats@yahoogroups.com, "robrohdeszudy"
      > <robrohdeszudy@y...> wrote:
      > > Hey Mr. White. Just found this post. Your "tranmission" is
      > brilliant!
      > >
      > > A couple questions:
      > >
      > > 1. Where'd you get the phenolic disk? What should I look for.
      > >
      > > 2. Air spring? Like in a pickup truck?
      > >
      > > 3. What size and number of belts did you use?
      > >
      > > 4. What thrust bearings did you use?
      > >
      > > I'm excited about homebrewed marine transmission!
      > >
      > > Many thanks,
      > > --Rob
      > >
      > >
      > >
      > > --- In AtkinBoats@yahoogroups.com, "oldbingey" <bingey@r...>
      wrote:
      > > >
      > > > The propeller of my outlaw Rescue Minor is belt drive using one
      > of
      > > > those poly-vee belts like on modern cars. That allowed me to
      > get
      > > > the reduction needed (4 to 3) at the shaft to turn Atkin's
      > > > recommended propeller with the 3,600 rpm Kubota engine. The
      > > > propeller shaft carries the thrust bearing. I described the
      > > complete
      > > > machinery setup in a bunch of articles in "Messing about in
      > Boats"
      > > > but I'll briefly list the peculiarities: The engine is a 20
      > hp.,
      > > > ($1,300 at the time) three cylinder tractor engine which was
      > > > purchased without a bellhousing. The weight was 134 pounds in
      > > that
      > > > configuration. The engine is cooled by a flat plate copper
      keel
      > > > cooler flush with the bottom of Atkin's "box keel." The
      > exhaust
      > > is
      > > > raw water cooled by a "Shur Flo" diaphragm pump adapted to
      drive
      > > > directly off the camshaft of the engine. The exhaust manifold
      > is
      > > > wrapped with copper tubing in which the exhaust water flows.
      To
      > > > minimize the overhanging load on the crankshaft from the belt
      > > > tension, there is a spring loaded tensioner between the output
      > > shaft
      > > > of the engine and the propeller shaft. I had an air spring in
      > > there
      > > > originally so that I could have neutral and reverse by pivoting
      > the
      > > > rear of the engine up and down with a foot operated lever to
      > loosen
      > > > the belt for neutral and then, by further depressing the pedal,
      > > > cause a rubber tire attached to the belt drive sheave to
      contact
      > a
      > > > phenolic disc attached to the driven sheave. Initial
      depression
      > of
      > > > the pedal released the pressure on the air spring and releasing
      > the
      > > > pedal allowed the pressure to build back up and re-tension the
      > > > belt. The air came from a small electric compressor which
      also
      > > > blows the horn. I intended to rig an engine driven compressor
      > and
      > > > air start the engine so I could completely eliminate the
      > electrical
      > > > system but I never got around to it. The wiggling of the
      engine
      > on
      > > > its soft motor mounts eventually (after about 800 hours) wore
      > > enough
      > > > slack in the air spring rig so that it started clattering so I
      > > > removed it and made the spring belt tensioner I have on there
      > now.
      > > > I never used the reverse or neutral anyway. The boat will
      turn
      > in
      > > > its own length at idle. It has proven to be a quiet and
      trouble
      > > > free rig.
      > > >
      > > > Robb White
    Your message has been successfully submitted and would be delivered to recipients shortly.