Just a few parts made at the shop.

   Scott- Iron Design


   Excellent work.  You can obviously handle the
  job.   The problem with
   hanging rotary engines in all types of aircraft is
 that a
  single
   immutable fixture will not suffice.  You need
 a
  fixture that can deal
   with different thrust lines, different thrust off
 sets and
  different
   ways of attaching the engine mount to the
 firewall.  I've come up with
   something that works but maybe you can build on my
 efforts
  to create
   an even better design.  Are you interested?

    Jerry

   I'll support you Scott. There are people out there
 that
  don't
   want to build their own. Jerry has gone through a
 lot of
  jigs and
   motor
   mounts in the last 11 years that I have known him.
 We have
  gone down
   a lot of roads that we had to make a U turn on. :)
 The
  attached
   jpgs are a brief history. Read all of this while you
 are
  at it too.
   http://www.rotaryeng.net/motor.html

   Paul Lamar




  Jerry,         I would be
 interested, with Pauls
  help/knowledge of what is
  required, we can do almost endless set up of one of fire
  wall jigs,
  as long as I know the thrust line angle, and fire wall
  hole
  placements... then we can make that fire wall blank on
 the
  CNC laser
  bed to pin point accuracy for the bolt placement.  Then adjustable
  fixtures for the balance.  I will pick out an
 example
  photo for a
  super cub look without the mount but with the engine.

  Paul if you could send my email address to Jerry and we
 can
  take the
  little details off the list thread line.

  there are some great things that can be done with solid
  design work,
  but we still needs someone like Paul for calculated
  placement.

  Scott

  Scott- Iron Design L.L.C.
  Scott Weinberg
  13631 Vail Ave
  Clarksville, Iowa 50619
  319-276-4400 home/office
  319-404-4401  cell/shop/office
  scottw@butler-bremer.com
  http://www.irondesign-airparts.com/Tailwheels.htm


  jerry@jerryhey.com

  Paul Lamar



  Paul -- Have you designed a Bearhawk Engine Mount?

 Bearhawk is designed for 180 to 250hp powerplant. I'm
 building as light as
 possible, so 180 to 200 hp Renesis is the goal.  The
 Bearhawk is
 designed at 6.6G Utility, 2500 pounds.

 http://www.bearhawkaircraft.com for more details.

 Tom Walter

 Not yet.  I need some information to do it. I need a
 sketch of the
 firewall showing the position of the motor mount hard
 points, the position
 of the thrust line, the engine off set angles both side to
 side and up
 and down as well as the distance from the firewall to the
 prop flange.
 Perhaps a copy of the manufactures fire wall dwg if you
 have it.

 Here is what Scott or Jerry needs to get an accurate
 position of the
 firewall hard points. Five strips of steel sheet metal one
 inch wide with holes
 near the ends that represents the distance between those
 hard points.
 Mail or ship those strips to Scott or Jerry so your new
 motor mount
 will fit exactly. If the strips bolt to your firewall  exactly the
 finished mount will also fit.

 Here is a sketch of the concept.

 Go for a p-port 250 HP. It will help you get off the ground
 quicker and is no
 heaver than 200 HP. Unless of course you don't want to take
 your engine apart.

 Paul Lamar


Paul,

I'll get the drawing of the firewall and dimensions  Tail is
offset, so thrust line is centered.

My Fuselage is an AviPro Quick Build, so mounting holes are
lined up nicely, thanks to their massive jigs. The designer did
all of his designs by paper and pencil. No DWG drawings.
Interesting part was a friend ran all the numbers though his FEA
analysis and every tube was "just right" for the job given the
design and materials used.  Amazing as we didn't think it was
possible.

I've got O/A and TIG welders, in addition to lathe, milling
machine (DRO is fitted), etc. So can build pretty much what I
need. I bought the AviPro fuselage to save time.

Good point on the strapping.  I'll confirm measurements with the
DRO on the mill cutting drilling straps.

Yes, one of Scott's Iron Design tail wheels is also on my
fuselage. Scott -- Didn't realize you're looking at Rotary
powered Patrol.  Elden Yates used a bed mount on his 13B
Bearhawk, I think he based it on the RV10 mount the Cozy Girls
are selling, but not positive.  The S-beam mount is lighter, and
with a Mill & DRO no problem making up the oil pan.

I'm looking at the Renesis as a neighbor flying his RV7A with
one is the quietest airplane in the neighborhood. The Renesis
side ports help with that bark, and muffler life.  One of the
fellows had a Turbo ports on his RV7, and is still working on
getting more than 10 hours of muffler life from it.

Tom Walter

Where are you Tom? I'll do the mount and send you the dwg with dimensions.

The trick is make your own mufflers out of .065 thick 321 SS and you will
have no problems. Here is a bunch of muffler suggestions
for 13B's.

Don't put anything inside the muffler as it will melt and come out.
An exception is a cooled .065 wall center tube. You can put a center tube through
a tangential muffler and force cooling air down the tube. Makes a good
cockpit heater or carb heater.

For non tangential mufflers mounted on the bottom of the aircraft
you can use one or two pipe(s) in and two smaller ones coming
out for lower noise. The smaller the down pipe the quieter the muffler.
It is a trade off with back pressure on the engine.
That applies to tangential muffler mounted under the cowl as well.
The flat parts of a fish mouth must be stiffened with sheet metal
angles welded on.

If you want to cut weight and spend more use .035" thick inconel.

Paul Lamar