undercutting half shafts?

[02GF74]

yep - you're right ; the end of the meshing has to be at the sharp angled part; obviouslythe teth don't contact all the was as indicate by the wear - oops! it was my first post this morining !

[Diff]

It seems to me that although one has failed just after the point at which the splines are formed(one laying down), the other will almost certainly have failed very close to the same point, namely the end of the splined section. This is very common and almost certainly caused by metallurgical changes or stress which occured in the shaft during manufacture or any treatment of the splined part.

Most broken shafts I have seen have broken at or near this point. In my experience it is rare for a shaft to break in the middle(though not unheard of).

Regards,

Diff

[Astro_Al]

Hey no problem - hell we start an hour earlier over here, so I'm having a coffee break while you are still bleary eyed! Good excuse!

Al

Diff - yeah, that's what I said earlier about the capacity of the shaft being reduced by the magnitude of the internal stresses. I guess they don't do any heat treatment after making the splines to alleviate the stresses... So yeah, as you say it seems reasonable to expect shafts to break at this point.

Though I have to say, the break on the shaft standing up is at a point where the splines are still at full depth - there doesn't even appear to be any tapering down towards the shaft before the shear.

Al.