Need outboard drive shaft shortened

[cnccutter]

I need my outboard Drive Shaft shortened and spline re-worked on end (see pics) It is a .55" shaft turned down to .5" at the end with 4 tooth spline. I need it shortened 5" and re-splined. I'm a wood guy thats wants to do a little fishin' before summer ends. You guys are the greatest - Can anyone out there help?
Mark

[abcmojave]

I do not know if anyone has helped you yet but let me know:
what is the material
what is the total length
what is on the other end
tolerance required

I will let you know if I can help out.

[cnccutter]

Thanks for the help, I think I found a "new" used one on ebay.

Mark

[Konrad]

This might work.... cut it off, turn the end to a 3/8 thread about 5/8 long, turn the other shaft with a 3/8 taped hole and loctite it together.

[NVTCNC]

About that reading and lock tight idea. It may need to be threaded left handed.
Thread it, chamfer it slightly and weld it. or pin it. would be my suggestion.

[fatal-exception]

This might work.... cut it off, turn the end to a 3/8 thread about 5/8 long, turn the other shaft with a 3/8 taped hole and loctite it together.

Even welding drive shafts back together is not recommended. I have my doubts that threading and loctiting would work for very long. What happens when you slam it in reverse?

If you were to cut the shaft down, cut a 5" chunk out of the middle, chamfer both ends to leave lots of room for weld. Make a steel sleeve that will slide over finish ground splice. Weld the 2 ends together, grind smooth. Slide the sleeve over the splice, weld around both ends of the sleeve.

Some guys also drill holes in the sleeve so that they can rosette weld in several places also, but in my opinion, there's not a lot of additional strength added by doing so. I've seen CV shafts shortened using this method and they seem to hold the HP.

This might be easier than machining those features again, especially the splines.

Paul

[NVTCNC]

so for big bucks one could shorten it and then cut new splines on it, which may or may not give you the same heat treat on the splines but doubtful. But then slamming it into reverse could break one that has never been modified, but also , if your drive shaft from the engine to the lower end is anything like mine, then the drive shaft does not reverse in that drive line unless the engine will reverse direction along with the crankshaft. Most reverse shifting is done between the prop shaft and the drive shaft so only the prop shaft is subject to reverse spinning. The old mercury in line 6 cylinders from the 1950's were like that in that they were direct drive, and the engine would run in both directions buy switching something in the magnito and starter to allow for forward and revers. They called it the "dockbuster" because it was dangerous. They don't make them like that anymore.
Whatever, you should be gentile with it unless you want to get stranded on the water.

[Konrad]

Welding is kind of iffy if you don't know what steel you're dealing with, especially
this small of a drive shaft, most likely a alloy steel...preheat and you might be OK ..still,
the weld most likely will bent it out of concentricity too much, I would rather silver solder
a stepped shaft or a threaded shaft...but give that loctite a test first...it has
unbelievable strength, ..give it a torque test first, you can always solder later.

[NVTCNC]

yea silver solder would be better than welding it, good idea.