I keep coming back to this design for that and other reasons.
   Also because it can be retrofitted to Tracy's gear box.
   The stiffness  of the silicone blocks can be almost anything.

   Not because it is my design :)

   Paul Lamar

   Paul, I am willing to do some of the leg work getting these parts
  made if
   you like. Industrial metal supply is a few blocks from where I
 live,  they   can cut most of it. Plenty of other cutting options
 nearby as well.

   And to get a prototype made, I can weld it up too. Have an 84
  syncrowave
   waiting for a job.

   Ed Carver

   Great Ed go for it. I think there are some laser cutters in your
   neighborhood.
   I am in the boonies when it comes to industrial stuff. Are you up
   to speed on Rhino or Solid Works? Most laser cutters guys can take
  Solid
   Works
   files. I can send Rhino files that will load into Solid Works.
   Mazdatrix sells suitable ring gears. Does Industrial metal supply
 sell   4130   sheet?   Use a .090" for the flex plate. A bit over
 kill IMHO but fine for   a test prototype. I'll test it on the RV4
 after I get a few hours   on it.

   You might want to make a prototype with cheap sheet steel to be certain
   everything fits on a counter weight.

   Get all that want them to send a deposit. Let me know what you
   need and I will send a check or cash your choice.

   Paul Lamar

   No rhino yet. I have Industrial metal working on a quote for the raw
   stock
   .090 4130. They do water jet and will take one of your rhino files
  maybe.
   I
   will be down there tomorrow to purchase the 1 inch tube for my engine
   mount.

   Ed Carver

   OK Ed. Let us know what they are charging for 1 inch .049 4130 so
 we  can   compare   prices.

   Check with IM and see if they can accept IGES or stp files.

   I can send them to you and you can give them a DVD or thumb drive.

   Paul Lamar

   They will take stp or iges.

   .090 4130 3'x12'=$525 I figured it is a little more than needed
 to make   20   parts.   They did not stock .050 4130 one inch tube,
 so I priced what they did   have;   .065 x 30 feet=$130

   They do water jet and laser cutting. Contact Terry Hill:
   thill@imsmetals.comHe apparently is the programmer for the lasers.

   I will, as usual, price this stuff elseware, IMS has usually been
 less   costly compared to other local vendors. They do discount for larger
   orders,
   and business accounts. Which does'nt include me.

   If the .050 tube is more than sufficient, I will us it for sure.

   Ed Carver

   I would go easy on the quantify of material bought  until we test
 this   thing.

   Try .049" perhaps somebody is not reading the list properly.
   Yes the .065" is over kill for the motor mounts  and too heavy.
   I have to leave in a couple of days for a week in Reno so I will
   not get the dwgs done until I get back.

   AC Spruce is not bad on cost.

   Paul Lamar

   I need to make a trip to ac spruce to get epoxy, etc. I'll pick
 up a  12x24   piece of 90 thou plate, it's about $30. I can make a
 prototype out of   cheap   stuff from ims.

   Ed Carver

   Great Ed.

   The splined plate is made from  part 675 in this dwg I think but
 I could   be wrong.   You might want to get one and find out. I'll
 see if I can get one when I   come   back from Reno if you can wait.
 I think Tracy adds a short cylinder  to act   as   a pilot in the
 eshaft.  I know it is not a stock manual transmission   clutch
 spline. The 2.85:1 planetary gear set is part number 582 and the sun
 gear   is   612. Ring gear is 592.

   Paul Lamar

   The 675 center shaft appears to be the only thing that the forward
  planet
   can ride on. So without seeing it, the back side of it must have the
  female
   splines. The brown part you drew shows the end removed but I am
 not  sure why   sense I have never seen Tracy's unit on the bench.

   Discussion has been made about creating a lighter psru. It
 would'nt  bother   me to begin to work on getting this done. If all
 it is' is getting  lighter   smaller bearing assemblies for front
 and rear, then we just need to  create a   new housing to hold it all.

   Where do I go to get the parts? Is Makco the place? I have a lot
 of   transmission shops nearby, that is why it only cost me $75 to rebuild
  my MPV
   Ford transmission clutch basket assembly. I have a 6 pinion planet
  set saved
   on my ebay page. I just don't know about the rest of it.

   Ed Carver

  Here's some ebay items for the center shaft:


http://cgi.ebay.com/**ebaymotors/FORD-4R100-SHAFT-**CENTER-USED-NO-TIP-<http://cgi.ebay.com/ebaymotors/FORD-4R100-SHAFT-CENTER-USED-NO-TIP-
 /400241251377?pt=Motors_Car_**Truck_Parts_Accessories&hash=**
item5d303cd431


http://cgi.ebay.com/**ebaymotors/E4OD-4R100-Heavy-**Duty-Center-Support-<http://cgi.ebay.com/ebaymotors/E4OD-4R100-Heavy-Duty-Center-Support-
 /120700943010?pt=Motors_Car_**Truck_Parts_Accessories&hash=**
item1c1a563aa2


http://cgi.ebay.com/**ebaymotors/E40D-4R100-UPDATED-**BEARING-TYPE-<http://cgi.ebay.com/ebaymotors/E40D-4R100-UPDATED-BEARING-TYPE-
 CENTER-SUPPORT-KIT-NEW-
 /330546282796?pt=Motors_Car_**Truck_Parts_Accessories&hash=**
item4cf618012c

  Ed Carver

  Hi Ed;
  There are several versions of that C6/E4OD/4R100 center shaft.
  At least 1 version has a center pilot extension on the splined end.

  The ones I have seen have a large bored cavity in the non-splined end
  (red in the image)
  I don't believe there is enough material to add a sun gear,
  although I have not checked the specific sun gear part you are
considering.

  I'm guessing Tracy has his shafts custom made with the correct spline.

  Cheers
  Cary

  Not custom made. Some part from some automatic.

  Paul Lamar

  I was wondering?since the rotary power pulses are so tame, that a drive
 system needs no damping of the rotary's torque pulses, then the gear
 chatter must come from a different source?.like anywhere else in the
 drivetrain. However, even with the existing damping system in
 Tracy's system, there is gear chatter.  Therefore, the current
 damping system is entirely superfluous:  not needed to damp engine
 pulses, and ineffectual against gear chatter!  It is my
 understanding that gear chatter can be dealt with in planetary
 systems by "tightening up" the system [larger gears, closer
 tolerances, stiffer metals etc].  So it would seem that any new
 damper would be no more effective that the old one against gear chatter.

  Even though propellers have fundamental frequency of vibration, as
 does the prop shaft, as well as planetary gears, and fairly large
 occasional torque shocks through the driveline during trailing
 throttle/free-wheeling scenarios, like coming in for a landing only
 seems to generate "chatter", then a proper approach to addressing
 the remaining concerns with Tracy's PSRU should only be limited to
 beefing up the 'flex' plate JUST to withstand gyroscopic forces, and
 also tightening up the planetary gears to avoid chatter.  Rubber
 dampers seem to be superfluous based on the above arguments.  As
 Bill O'Reilly sea:  Where am I going wrong?  Thanks.

  Gene Kahn

  They are tame compared to a four cyclinder but they are still
 there.  However the e-shaft is very stiff compared to a 4 cyclinder
 so they  do not cause e-shaft problems like torsional resonance or
 stress fatigue  cracks common in crankshafts.

  Gear chatter is a wide spread problem in all types of intermittent
 internal  combustion engines driving a gear box with a prop on the
 other end.

  It is near impossible to eliminate all clearances in the gear
 train due  to several factors. One factor is the heat effect that
 causes metal parts  to expand. Another one is wear. Fortunately the
 chatter RPM is well below  the operating range of the rotary
 aircraft engines so it is no problem at  all during landing, take
 off or taxi. The engine goes through the chatter  range so fast it
 is not noticed on start up. I am getting  to the point I wish  I did
 not bring it up in the first place :)

  Paul Lamar

 Well, I for one thank you for bringing it up and especially for continuing
 to educate me in this regard!  Thanks!

 Gene Kahn


Paul,

 A little pat on the back to you. This news letter and your web are a great
source of information. This takes a lot of your time. Thank you.

 As for the gear box chatter discussion; I think it is good that this was
brought up. It gets everyone thinking about what is going on in the
mechanical
systems. Comparing to the automotive parts base that is the supply and the
different operating conditions with respect to the expected and seen
results
is good. The knowledge base that lurks in the background and pops out now
and
then helps educate each other on design quirks and possible problem areas
to
watch out for. Gear chatter and the flex plate are just a couple of
examples.
Education and design while taking into account the end result and use
parameters will make flying safer.

 Education in the chatter problem is relevant to gear driven PSRU's of all
manufacture. Light load in either direction seems to be the problem.

 Design is the limitation of the loads expected and duty cycle of the flex
plate as Mazda views it, and when re-purposing for another use. They beefed
up
the center when building for the RX8 due to the greater load imposed by
greater power output. But that duty cycle is low compared to AC use, which
dictates a more substantial drive.

Dale Davies

We will know more after this week when Dave abuses the turbo rotary powered
RV6 in
the Reno air races :) Just kidding Dave. He is probably flying the RV6 as
we speak
from Mammoth Ca to Reno Nevada.

Paul  Lamar

Paul,

I second Dale Davies compliments to you.  I've learned a ton.  I'm just
waiting for you guys to decide what's best and I'll go with that.  But,
incredibly interesting to follow the discussions.

Van