If someone know which bearing Tracy use on prop shaft if yes
  what brand,ball or roller and
  bearing number



  Jean Prudhomme

  I don't have it here but I think it is a 1.3875" ID and
  the OD is 3.350". It is .75 inches wide. Double sealed.
  Inch series. Probably a Chevy Pick up truck rear wheel bearing.

  Search the internet for ball bearing makers and give
  them the dimensions.

  Paul Lamar


  Do you know if is a roller trust bearing or ball trust bearing??

  When you have a chance could you send me the bearing number and brand

  Jean Prudhomme


  It is a ball bearing Jean. The Chevy Truck has a lot of
  side load on the rear wheel while cornering so it must be
  a combination of axial and radial load.

  I am getting ready to go to Germany
  so I may not get out to the hanger for a couple of weeks.
  Try to find it on your own. Start with an auto parts store.
  Just measure the bearing they bring out and if the dimensions
  are correct that is the right one.

  Ball bearings are ball bearings.

  Paul Lamar


  Paul
  Your statement that ball bearings are ball bearings.
  "It aint necessarily so".
  It's over 40 years since as a design engineer I designed bearing systems but
  if my memory serves me well there are deep groove ball bearings that have
  greater axial load carrying capabilities than the standard type. If this
  particular bearings is required to take high axial loads then I would be
  surprised if it wasn't a deep groove type. Care needs to be taken in
  selecting the correct bearing for this application
  Bob Izett -Perth, WA

  Well yes that is true and I totally agree but any rear axle bearing
  THAT size will work. Tracy's prop shaft is an actual section of a GM rear
  axle. The side loads on the rear axle are similar to the thrust loads on
  a prop shaft. In fact the retainer for the ball bearing is the same
  way GM retains the rear axle ball bearing. Namely it is pressed on.

  Tracy has sold well over 100 gear boxes with many of
  them flying for the past 10 years so it must be OK.

  There is nothing seriously wrong with it but it could be designed
  to be as strong yet lighter in weight. The bearing itself is very
  heavy being over 3 pounds as I recall.

  I should have said a rear axle ball bearing is a rear axle ball bearing.


  Paul Lamar
  Hi Jean,
  Years ago when Tracy first started making PSRU's, I recall his website blog telling the
  story of
  several bearing failures. The bearings were of similar physical size but were from different
  manufacturers. This is a sealed bearing which means whatever lubricant the manufacturer
  put in is there for the life of the bearing. So maybe he stumbled on a lube difference.
  Bearings are
  manufactured to different tolerance classes. So maybe he stumbled on the wrong class of
  bearing
  a few times. The bottom line is why should you remake his mistakes? Just buy the bearing
  from him.
  If his axle supplier can get it and press it on, then he can get one for you. Sure he'll
  mark it up, but so will
  the auto parts dealer. At least with Tracy, you'll get the correct bearing and the markup
  profit will
  support someone who supports the rotary. Dave M


  I don't recall that was the prop bearing. As I recall it was the helical
  gear thrust bearing. Apples and oranges. I have the emails.

  I challenge anybody to show me two bearings of that EXACT size double
  sealed that have significant differences.

  Paul Lamar

     
I already contact a drive shaft manufacturer and i need a shaft of 24" long for my drive
and they can make it for $600.00 for a ligt weight shaft with 1"dia gun drill shaft
estimated at 8.5 lbs
with a 45mm bearings but if i can get to 1 3/8 shaft with tracy exact bearing it will be fine.

I already contact Tracy to have the shaft i need and he said it will be to expensive .

  I can reuse his housing to attach to the shock mount plate.

I do have all the parts on hand to built my angle drive at 3 to 1 ratio and i should
assemble it as soon i solved my bearing and shaft problem
I do have an aluminum spool with 28 splines and i need to rebrouch to 31 or 35 splines.

I can buy a rought housing from Tracy and do some machining to suit my shaft but i can by
pass his housing to have a lighter housing by using 2"I.D. x 3" O.D. and weld stiffner rib
of alum 1/4 thickness to the gear end housing

and it will be on one pce instead 2 parts with Tracy Housing lighter.


Jean Prudhomme                   


You cannot put a prop on the end of a 24 inch shaft. It is against the
laws of physics. It is just not a bad idea it is the LAW. The penalty
for breaking this law is a crash and possibly death.

Jean,

Read these web sites.
http://www.epi-eng.com/mechanical_engineering_basics/torsional_vibration_intro.htm
http://en.wikipedia.org/wiki/Torsional_vibration
http://www.bksv.com/Products/LaserVibrometry/TorsionalAngularVibration.aspx


Paul Lamar