Milling a shaft.

[Kent]

If you weld two sections together the difficulty will be alignment. Used to do a regular job very similar, the final part involved a dti big lathe and a big heating torch.
Trust me don't unless it's the only option available to you.

 

[addjunkie]

Last time i did one of these the cogs were welded on and it was then joined in the middle with a 40 mm long fine thread. Then a pin through just to make sure. It worked. like I said, once I see the bits, when he turns up, with measurments. I shall decide, on a plan of attack. It took him 8 months to bring the bits for the last pair of yokes I made for him.

 

[agrimog]

unless the shaft is hardned, the splines will last 5 minutes with the power transmission of anything but pushbike pedals

 

[outofthefire]

unless the shaft is hardned, the splines will last 5 minutes with the power transmission of anything but pushbike pedals

With respect i've known of addjunkie and his friends for a long time and between them they've built some fantastic bikes and trikes so i'd be surprised if things haven't been taken into consideration.

 

[addjunkie]

This has been considered, and is one reason why the weld on option works. In this case its very low power. So hopefully some heat treatment and a bit of case hardening will work, or itll be a couple of welds to fix it, as they say.

Now you have me perplexed @outofthefire

 

[Wallace]

Why copy the factory splines when you can use off the shelf sprockets for the jack shaft as it will be a one off?

 

[addjunkie]

They will be off the shelf sprockets. So shaft will be made to fit sprockets

 

[outofthefire]

Now you have me perplexed @outofthefire

I was beatamax on britchopper, for some reason im facebook friends with your good lady not you

 

[Gritineye]

unless the shaft is hardned, the splines will last 5 minutes with the power transmission of anything but pushbike pedals

Not entirely true, a surprising amount of half shaft splines I've rubbed a file on have been quite soft.

 

[addjunkie]

I was beatamax on britchopper, for some reason im facebook friends with your good lady not you

Thats because shes better looking than me. That was a great forum, shame its almost died.

Not entirely true, a surprising amount of half shaft splines I've rubbed a file on have been quite soft.

I butchered a pair for ford half shafts for a trike I built, there were suprisingly soft, to cut and shorten. Outer shell of the metal was as hard as hell, but soft inside. Machined easily enough to weld then sleeve, then weld again. Cleaned up one of the splines that was damaged with a file from it being dropped. Wasnt too hard. Thinking en16t or possibly 24.

Though this job may be made more difficult as this morning i was taking a very fine skim of a 65 year old starter motor for someone. And couldnt get the gears on my lathe to change.... So screw cutting wont be possible till I sort this.

 

[nickk]

if you lay too much weld on you could overheat the oil seal behind.

 

[Wallace]

They will be off the shelf sprockets. So shaft will be made to fit sprockets

Sorry, I meant engineering sprockets not bike specific and a shaft machined to suit. What about using a pair of gearbox layshafts from the same engine end to end shortened to suit with a coupling?

 

[mike os]

Easy job on a horizontal mill, bit of a faf with vertical

 

[addjunkie]

Easy job on a horizontal mill, bit of a faf with vertical

As i only have a vertical, itll just have to be a faffffffff.

if you lay too much weld on you could overheat the oil seal behind.

What oil seal, this is just a sprocket each end of a shaft, between two bearing blocks. That I need to make first.

 

[Screwdriver]

Not entirely true, a surprising amount of half shaft splines I've rubbed a file on have been quite soft.

For some reason, I have it in my head that gearbox shafts are case hardened, not fully hardened.

 

[brightspark]

most halfshafts are made of en19 i believe easy to machine then hardened

 

[Gritineye]

most halfshafts are made of en19 i believe easy to machine then hardened

Mine are made of EN19T, nitride hardening carries a minimum charge is £150. The old ones definitely weren't case hardened in any way at all.

 

[Scruffywelder]

Think I'm with Wallace on this a one. Any reason not to use taperlock sprockets of the right pitch/width and just machine keyways in the shaft?
I've cut splines on a VM before and it was a total faff to do (method as previously described by PDF).
Place I used to work had a gear hobbing machine that we could do agricultural PTO splines on...

 

[Shox Dr]

For the hassle, I'd look at farming it out to one of the Co's that modifies half-shafts, you maybe surprised how cheap it will be. I was asked to make a new propshaft for a K1000 based Trike (Chris Ireland build). I coudn't buy the bits for what we got it made.

 

[addjunkie]

I remember this build you speak of, and i agree often easier and cheaper to farm out. If it were a prop, it would be farmed out, if i wasnt splicing two together, as we have a prop company in the family.

But this is an odd ball. Shaft with sproket on each end. Like i said earlier, when the bits arrive I shall decide on a course of action.