Who re-splines driveshafts??

[Mouthfulloflake]

you are correct Romack,

there would be ALOT of engineering in this to make it strong if it were to be welded together.

both parts need to be heat treated before hand, and put into what is commonly refered to as a state of " solution" this usually requires an oven with an argon atmosphere, and a temp range of 1900 for probably half an hour or so, and then a slow cool down period.

when the part comes out, it will be softer than normal, and it will be larger than normal.

the parts will be welded together, and then another heat treating process, called " precipitation" lower temps and alot more time involed ( like 20 hours or so)

this will make the parts hard again, and they will shrink back to the target diminsion ( ideally at least)

Now ive only done a few stainless alloys, so the temps and numbers could be way off, but Im guessing that that the basic theory would be similar.

likely the part will be machined AFTER the final heat treat process, to get a more accurate diminsion. but that will be hard on tooling, hard stainless is hard to cut.

it could be cut while in solution( soft) , but then the diminsions change once its hardened back up.. would be hard to arrive at the target tolerence.

I have seen splines cut on a bridgport mill with an indexing tool.

and ive heard of them being rolled, but I am not fameliear with that process.

there are alot of companies out there that do axle shafts, its pretty common in the automotive realm, but thats a different material, and often, they are shortened in the process, so they just cut back, and spline the material thats already there.

Just like to point out this is not a correct statement as it stands... Hardness does not equal strength. And I hope the other end is going to the same hardness or that will just be the one wearing away. Also this would make the shaft more brittle unless he just is doing surface heat treating and leaving the core soft.


As to the welding weakening the shaft. You have a heat effected zone right on the edge of the weld that causes that. You should be able to heat treat the part to eliminate in. Definitely can lower your corosion resistance though as mentioned too.

turning nerdy analysis off now...:dunce:

 

[Ollie Rastabean]

I cannot imagine that Yamaha heat-treats these shafts. Too expensive. The shaft on my SJ was soft and gummy. Def not heat -treated.

Nothing exotic on the splines either. Shaft probably turned as a single piece + splies cut as a secondary op.

-O

 

[Ollie Rastabean]

Here is a crazy thought. What about a different interface between the two parts.

Why does it have to be splined.

How about a square end to the shaft and a square pocket in the short shaft.

A square end in the shaft can prob be machined into the stripped shaft end.

The short shaft could be bored, a new plug of mat'l inserted and then the square pocket machined.

Flame away boys!:headbang:

-O

 

[yamaslut]

Here is a crazy thought. What about a different interface between the two parts.

Why does it have to be splined.

How about a square end to the shaft and a square pocket in the short shaft.

A square end in the shaft can prob be machined into the stripped shaft end.

The short shaft could be bored, a new plug of mat'l inserted and then the square pocket machined.

Flame away boys!:headbang:

-O

or just deeper splines

 

[LBE]

Here is a crazy thought. What about a different interface between the two parts.

Why does it have to be splined.

How about a square end to the shaft and a square pocket in the short shaft.

A square end in the shaft can prob be machined into the stripped shaft end.

The short shaft could be bored, a new plug of mat'l inserted and then the square pocket machined.

Flame away boys!:headbang:

-O

That is a good idea, however, the reason splines are used, on this as well as in automotive aplications, the splines provide more surface area to distribute the load over. You could have a slot receptical and a flat end on the driveshaft that goes in, but then your load is basiclly resting on two points.

I hava Jeep and this seems to be the logic to beefing up axle shafts, increasing the spline count to distribute load over the diameter of the shaft, less likely to strip and distributes torque to prevent breakage.
If that makes sense?

But a good thought.

 

[WaveDemon]

Here is a crazy thought. What about a different interface between the two parts.

Why does it have to be splined.

How about a square end to the shaft and a square pocket in the short shaft.

A square end in the shaft can prob be machined into the stripped shaft end.

The short shaft could be bored, a new plug of mat'l inserted and then the square pocket machined.

Flame away boys!:headbang:

-O

I'm no mechanical engineer but here is how I see it. The flat sides of a square shaft end won't mate with the square side of the coupler. the corner of the small square with be turned by the flat of the large square. I think that point will coutinually wear untill the small square will spin inside the big one.

 

[LBE]

or just deeper splines

A good idea, more surface area = more torque distribution.

 

[WaveDemon]

looks like LBE beat me to it while I drew up my example

 

[waxhead]

there are some great ideas here guys
Let us know what you come up with
i am interested to see how it turns out for you

 

[Idok]

what about a SINGLE shaft that ran the entire length......it coud somehow be inserted in the short shaft..then when the pump removed the shaft would still be inserted..

kinda like in a seadoodoo..

 

[waxhead]

yeah you could do that

you would just have to change the pump so that it ran a kawasaki style of prop so you could get the pump out
but it would work

 

[Ollie Rastabean]

what about a SINGLE shaft that ran the entire length......it coud somehow be inserted in the short shaft..then when the pump removed the shaft would still be inserted..

kinda like in a seadoodoo..

Dont be getting any funny ideas with my Kawi pump.

Just realized something. PM sent.

-O

 

[h2odesperado]

wait... would more splines be kinda like a 6 point socket vs 12 point socket? is that relevant here at all? Which one can you transfer more torque through? 6 or 12?

 

[waxhead]

wait... would more splines be kinda like a 6 point socket vs 12 point socket? is that relevant here at all? Which one can you transfer more torque through? 6 or 12?

I think the more splines you have is the strongest for the reason you have a rocking action and not just a constant push as in a socket
i think more splines spreads the load and handles the wear more

 

[yamaslut]

wait... would more splines be kinda like a 6 point socket vs 12 point socket? is that relevant here at all? Which one can you transfer more torque through? 6 or 12?

6 point is stronger, due to the depth of the cut... 12 just makes it easier to fit on the nut/bolt for tight areas but will strip easier...

 

[yamaslut]

I think the more splines you have is the strongest for the reason you have a rocking action and not just a constant push as in a socket
i think more splines spreads the load and handles the wear more

if they were the same depth they would be comparable.. a 12 is like half as deep of a grip on the nut as 6... :wink:

 

[WaveDemon]

Here is a crazy thought. What about a different interface between the two parts.

Why does it have to be splined.

How about a square end to the shaft and a square pocket in the short shaft.

A square end in the shaft can prob be machined into the stripped shaft end.

The short shaft could be bored, a new plug of mat'l inserted and then the square pocket machined.

Flame away boys!:headbang:

-O

Even though I think it will fail eventually (so will another used one) I'd be willing to try a square if it were super cheap.

 

[LBE]

I think more splies is stronger, but I'm sure there is a paint where more splines are weaker(to thin). The idead is to find the balance.


This is the only aplication where I can't think how to fix this problem with ducktape and/or zip ties.

WWGD-------------->What Would Grandpa Do.....no tape, no ties.HHHHMMMM

 

[superramjet]

Another idea would be to use the gp1200r shafts, they have a slightly larger spline area (bigger diameter) than the sj shafts. The driveshaft could be cut down and resplined with the larger splines. Those shafts hold up well in high hp gp12r and gp13rs.

Why do they wear so fast in the blasters anyway? Does the hull flex to much, do they need a bulkhead to pump support bracket?

 

[superramjet]

do you care to share who that company is?

I will ask and get back to you. I never asked the name of the company who did the work. He said it was a machine shop nearby. I'll tell you if i can find out.