Hi Paul!

 Here's a couple pics of the acrylic damper assem mockup. Presently, the
 original 6.9" diameter for the damper section looks to be a little too
 small when using the 1/2x1x7/8 blocks, as there is conflict with the large
 washer ring. The image shows the blocks standing on their 7/8 side,
 instead
 of the one inch side, and it's still a bit too large.

 What do you suggest is the next step?

 Ed Carver


 Looking good Ed.

 The shaft project has run into a snag. I need to get the material back.
 Michael that owns all those big lathes was forced to get a full time
 job to pay the bills. He just was not getting enough biz to keep the
 doors open. I'll see if I can get in touch with him tomorrow after
 his work. I may be able to cut them to length with a carbide chop
 saw I have. Jim thinks he can do it with his lathe. Just not as fast
 as Michael.
 ------------------------------********------------------------**--**
 --**--**-----

 As to the flex plate what rubber blocks are you using?
 I assumed we would use custom molded rubber blocks to fit.

 At least that is what I said in an old message in Sept.

 -------- Original Message --------
 Subject: Gear box pictures
 Date: Mon, 19 Sep 2011 16:08:01 -0700
 From: Rotary Engine <rotaryeng@earthlink.net
 To: AAA Put this in the To box <rotaryeng@earthlink.net

 lots of snips....

 "Now it is possible to design the concave rubber blocks with enough
 expansion
 clearance so no axial force will be generated."


 ------------------------------********----------------------

 OK I think I have it figured out. What you are saying is the 1" by .5"
 rectangular tubing
 is too big to fit the 6.9 inch diameter and the stock steel clamp ring.

 I probably made a mistake on measuring the clamp ring diameter. What
 number do you
 have on that?

 We can do one of two things. Cut down the clamp ring plate in a lathe or
 go up on the 6.9" dimension
 slightly. What do you think?

 Paul Lamar


 It's why we made a mockup. The ring diameter is odd in that it extends
 outward past the bolt centers more than it does inward. Seems natural move
 the diameter out at least .200". The ring is 5.115" OD.

 Is there in the plans something to contain the rubber on the inside
 diameter of the .5x1" blocks? The spline plate inward extension will ride
 about .100" off of the e shaft.

 The spline plate as shown in my photo does not have the OD cut down to
 your
 spec. That is because I am not sure if I will use it. I am going to use a
 longer input shaft, and hence, a different spline plate.

 Gotta do what you gotta do Michael. I'd be in the same boat if it were not
 for the mass of old porsches and parts I collected over the past 25 years.
 Even with the bust of the Euro, Germans still want their lawn mower engine
 powered old 911's back. (I will always tease porsche lovers because they
 whine too much when they lose at the track) ;)

 A chop saw will easily cut the alum shaft material. I may be able to get
 the shaft bored in the EAA hanger. We have a couple lathes in there, but
 they are on the small side and I would need to create some sort of
 bearings
 +to hold the shaft at it's longest extension out from the chuck.

 Perhaps Michael can do it as a side job. Can 4.5" material fit into the
 bore of that chuck? The easy part for him would have been turning the
 housing, which has a much larger diameter. That part is probably out of my
 size range because it it too long for my mill.

 Ed Carver

 To cut it down to fit it must be 4.750" dia..

 What we have going for us is the large 4130 plate is .096 thick while the
 mild steel stock plate is .062" thick.

 I'll try to have another talk with Michael today.

 Here is flex plate rev 4 with with a 7.586 diameter.

 We measures Jim's chuck and we can get 4 inches in there no problem.

 Things are getting hectic around here so after Christmas is going to be
 it.

 We have a pack of relatives staying with us.

 Paul Lamar


 Here's a list of the radius points, all dimensions +- a few thousandths.
 Clamping ring id:        r1=1.55
 Clamping ring od:       r2=2.56
 Damper blocks id:      r3=2.76
 Damper section od:    r4=3.780
 Ring gear id:              r5=5.655

 We now have about .200" between the blocks, (r3) and the clamping ring OD,
 (r2). It looks to me as though we should weld a wall around the clamping
 ring to act as the inner housing for the rubber blocks.

 The ring gear id is taken from the 1988 RX flex plate ring gear. This is
 the gear you can just barely see in the photo I sent of the acrylic mock
 up. I removed the ring gear by cutting the welds holding it in place to
use
 it for this project. Your ring gear may be different. The stock flex plate
 has .370" of the outer edge rolled 90* to hold the ring gear securely.

 The depth of my 88 flex plate from the top of the ring gear to the flex
 plate mounting surface is 1.170". Subtractions for various thicknesses
 shown below:
 New plate mount to counter balance: -.095"
 New spline plate:                             -.095"
 Leaving us with .980" for the rubber blocks, and the .5x1" steel
 rectangles.
 We can probably lower the spline plate into the damper a 100 thou or so to
 help keep things in place.

 I remember some discussion on the type of rubber to use as damping
 material. When should I be concerned about this? When I know what it is I
 will just go buy it.

 Ed Carver

 I am going to go over this when I am a bit more awake :)
 Silicone rubber is preferred as it will tolerate 500 F.


 Paul Lamar


 Here is what I have for revision 4.


 Paul Lamar



Attached is a sketch of our damper plate sectioned at the middle, with the
new unit on the bottom, and the 88rx flex plate on top.

Image shows how we can make it contain one inch thick rubber while still
using the original position of the ring gear. By moving the 16 hole plate
to the inside of the ring, it shortens the rubber approx. 5/16.

I have completed all of the plates. There was enough material to make two
16 hole parts. The mount plate fits nicely onto the counter balance.

The one inch tall containment wall is all that is needed to finish the
parts for welding. Would you like it one inch, or 11/16(approx)?

Ed Carver


I think I found a guy that can do our prop shafts in Santa Paula.
More about this after Christmas.

Paul Lamar



I am currently creating the mold for sand casting the prop shaft housing.
It is easy to do on my mill. Should be most of the way finished with it
tomorrow, including the core box. At present, the block I delivered to you
probably is'nt necessary.

Before cutting and boring the prop shaft material, let me know how much you
need of it; It is possible I may want a longer shaft than the previous
standard length.

I should also be able to use my mill to finish trim the housing, and
possibly do the internal bore for holding the bearings.

Regarding the 100mm bearings, there are several vendors on ebay selling our
size 6820, with steel balls, lowest price about $18 each when purchasing 10.

What do you think about the possibility of using the apex oil pump shaft
for pumping gear oil through the prop housing?

Ed Carver


I have to get the aluminum shaft material back. The guy dropped the ball.
I have another shop here in SZP that can do the final job on an NC lathe.
He has a 2 inch boring tool that works on the NC lathe.

Paul Lamar