Driveshaft Repair
 

Hi Guys,
I have a solid driveshaft out of my 38 Pickup, that has a badly pitted front bearing surface. The splines and centre bearing surface are in good shape.
Just wondering if anyone has successfully repaired the bearing surface on a driveshaft and how.
What is the specified finished diameter in this area?
Your suggestions appreciated
Dave

Re: Driveshaft Repair
 

Is that portion of the drive shaft case hardened? Run a smooth file across it to see.
If it is not case hardened do you think it would be k to MIG weld the pits, file them smooth and run it with the bearing. This is pure speculation. Just an idea.

Re: Driveshaft Repair
 

Ford's spec. wear limit was .005"
I don't know what the original diameter is though.
Is there a place on the shaft where the bearing didn't ride u could mic it? Just behind the splines perhaps....

Re: Driveshaft Repair
 

Ford used good metal when they made those shafts. They are steel but they shouldn't be as hard as case hardening. I've seen axles welded up by TIG methods & turned back down. Only problem I see is cost for labor involved and whether you could find someone to do it or not. The shaft is long so it may need extra shaft support other than the lathe chuck but a large enough lathe should allow for the shaft to fit through the spindle & chuck OK. A lot of machine shops have big equipment to do stuff like that.

Re: Driveshaft Repair
 

There is a process called spray welding, and the product and equipment was manufactured by a company called Eutectic the last time I saw it used in a machine shop. The process is low temperature, so there is no distortion if done correctly They are now called Castolin-Eutectic. Check the local machine and welding shops in your area.


https://www.castolin.com/en-CA/Flame-Thermal-Spraying

Re: Driveshaft Repair
 

Haven't been around a shop in sometime, but electric motor rebuild shops used spray welding at one time. They should also be able to turn the shaft back down. This is a common type of repair on electric motors. At Boeing we would chrome plate undersized parts up to size. The guys running the plating could just about get it dead on!

Re: Driveshaft Repair
 

Boat shop, they repair propeller shafts.
Bruce

Re: Driveshaft Repair
 

Plating if the pits are deep will cost....you pay by the thickness needed.
For spraywelding you got coldspray where the sprayed on material doesn´t melt the original...just fuse into the surface....and there´s always a risk it will flake if something goes less then perfect....but won´t distort the shaft.
Hotspray fuses the sprayed material togetter better but the more heat the bigger chance of a warp.
For it to fuse well the surface needs to be clean...grinding it down and spraying on new material works better then trying to fill pits from my experience.

Re: Driveshaft Repair
 

Yep, the cost was not a consideration. I don't think it is a practical approach for an individual, the topic just jogged my memory of how this type of problem was solved when you had access to unlimited resources! :)

Re: Driveshaft Repair
 

cost is never a consideration when it's an FAA approved repair or buying a new part that will cost ten times the repair cost.


the costs built in to those parts make me gag. I work at a machine shop who supplies OEM parts to engine manufacturers and does the approved repairs on some of the same parts. in many cases we make more money repairing parts than we do making them brand new.

Re: Driveshaft Repair
 

Thanks for the suggestions and insight. I will contact an engineering shop in Brisbane and get a quote. I will also advertise for another shaft in better condition.

Re: Driveshaft Repair
 

if you can't find a good original I have one more thought here, it's not a crazy piece of material. take it to a couple machine shops and see how much they will charge to have a new one made. We've done it to make quick change shafts which are almost the same thing, just shorter than your driveshaft.

Re: Driveshaft Repair
 

I didn't bother to mention the hard chrome or Chromalloy processes due to the cost. They turn worn area down to remove the surface irregularities. They plate it or plasma spray it back above specs then precision grind it back down to spec. I've had more than a few shafts for helicopters done but they are 6 to 10K $ shafts so they are worth the trouble & expense.

Re: Driveshaft Repair
 

Dave, I would not use that shaft.surely some one in the club will have a better one, maybe Erol or some one outside Brisbane
Lawrie

Re: Driveshaft Repair
 

Yes thanks Lawrie,
I have come to that conclusion too after talking to the spray metal experts. The stuff has a tendency to come off in some applications.
I will ring around our members.
As a side note Lawrie, we missed you on the Spring Tour , but enjoyed your western adventure blog.
Keep up the travels,
Dave

Re: Driveshaft Repair
 

Yes Dave ,we had a great time away in the 33. 7000klms no drama,
will see about an article for the mag.
Lawrie

Re: Driveshaft Repair
 

Dave I have one I’ll dig out for you it’s still in the torque tube I don’t know what it’s like Dan.

Re: Driveshaft Repair
 

Thanks Dan,
ill call you.