How do I determine if my center driveshafts are bent?

[parcou]

Cleaning up the RC shop today, I found some center driveshafts. With dogbones on each end, I cannot roll them on the bench to see if they are bent.

I tried putting them in my drill, but that was no help getting them in straight or locking them in was a pain. See if there are any tips on determining if the center drives are bent without putting them in a rig.

Thx

 

[calebgilmore]

Can you put them down on something skinnier than the distance between the ends? then they would be rolling on the center of the shaft and you'd see it wobble/jump.

 

[King blitz]

Try using a 2x4 board.place the ends on the outside and roll the shaft up and down and see if it wobbles.you could also use your eyes..if your eye sight is good

 

[DLK83]

Try using a 2x4 board.place the ends on the outside and roll the shaft up and down and see if it wobbles.you could also use your eyes..if your eye sight is good

This, and hold a flashlight on the far side facing you, look for light between the board and driveshaft when you're rolling it, if you can see the light, it's bent

 

[Tex Koder]

Use any scrap piece of metal U-channel, place the driveshaft in question on top of the open side and roll it back & forth to see if there's any wobble..
If not, then the driveshaft is straight.

Something like this >

Or

 

[parcou]

Can you put them down on something skinnier than the distance between the ends? then they would be rolling on the center of the shaft and you'd see it wobble/jump.

Try using a 2x4 board.place the ends on the outside and roll the shaft up and down and see if it wobbles.you could also use your eyes..if your eye sight is good

This, and hold a flashlight on the far side facing you, look for light between the board and driveshaft when you're rolling it, if you can see the light, it's bent

Use any scrap piece of metal U-channel, place the driveshaft in question on top of the open side and roll it back & forth to see if there's any wobble..
If not, then the driveshaft is straight.

Something like this >
View attachment 258570


Or

View attachment 258571

Thx all for the post. I will try these!!

Obviously, a large wobble is bad. How much wobble is acceptable? Or is the objective to have NONE?

 

[King blitz]

You could you use a ruler with a nice

This, and hold a flashlight on the far side facing you, look for light between the board and driveshaft when you're rolling it, if you can see the light, it's bent

This will all work well but if he uses a 2x4 board that's not leveled then you'll get a misdiagnoses.just make sure that board is flat and true and he will be fine

Thx all for the post. I will try these!!

Obviously, a large wobble is bad. How much wobble is acceptable? Or is the objective to have NONE?

No wobble is acceptable. I keep having a image of Fred Flintstone driving on square wheels lol.thats a whole lot of wobbling going on

 

[Diem Turner]

Thx all for the post. I will try these!!

Obviously, a large wobble is bad. How much wobble is acceptable? Or is the objective to have NONE?

I think it depends on for what it's being used. For bashing I don't think a little wobble is going to be a big deal. For high speed...probably best if they're straight. T-Works makes this nifty little device for straightening kinked drive shafts.

 

[King blitz]

I think it depends on for what it's being used. For bashing I don't think a little wobble is going to be a big deal. For high speed...probably best if they're straight. T-Works makes this nifty little device for straightening kinked drive shafts.
View attachment 258709

Wow I have something like that back at the shop but had no luck in the past.never been able to get a shaft perfect the way it was originally.even heating it up a tad bit to soften the metal.i rather just junk it and buy a new one .I agree for bashing maybey it doesn't matter as much but for speed runs any slight wobble is a no go...a wobble turns to a nasty vibration which isn't what we want
I've seen guys place the shafts on a solid base and heat them and beat the crap out of them and still not like it was originally..I can see if it was a really expensive shaft made of titanium maybey I see the reason for trying to repair it but for the most shafts out there I'd just toss it save your self a headache and free more time to bash