keyways

Many ways, shaper or slotter, of which you have neither, broaches and bushes, probably out of the equation as well. Last resort is a tool like a parting tool on it's side and rack it backwards and forwards using the lathe carriage.

De-luxe version of that is removing the nut and screw from the top slide and replacing it with a fulkrum lever to turn the top slide into a hand slotter.

level. Guides can make it a little easier.

Don Young (USA)

What's the difference between? I guess the latter only does slotting, while the former does more :), but how?

of which you have neither, broaches

- found broaches on

:) nice - wouldn't a broach just make a shaping operation quicker? A bit like a saw has many teeth :)

???

Got me, don't have a clue here.

probably out of the equation as well.

Hmmm ... "gear" in the lathe chuck, spindle locked (?)

As in

?

All good stuff, but I kinda hoped for something more ... immediate

Ah well,

Thanks,

-- Peter Fairbrother

Files?

Yes you do.

It's also called "a-hacksaw-and-some-files".

A method that hasn't yet been pointed out, but that does a very good job if there's room for it:-

Bore the hole in the gear oversize. turn up a bush to fit the bore and half the thickness of the key.

Cut a slot in the bush of the key width.

Loctite bush into gear.

Makes a very neat result and can be tested for fit before the Loctite is applied.

Worked for me with a pulley anyway.

Mark Rand RTFM

Yup - it has worked for me too.

Regards, Tony

The broaches come with slotted bushes. The bush goes into the hole that needs the slot cutting to guide and support the broach. If the keyway is deep, the broach may be pushed through a second time with the appropriate shim between it and the bush.

Mark Rand RTFM

To confirm I am visualising the method correctly, does the bush resemble a letter C in section?

Cliff Coggin.

Can you use a round key instead? dead simple then, slot shaft with ballnose endmill, and place sacrificial shaft in gear then drill hole 1/2 in gear 1/2 in shaft. If you have to use a square key then use a three square file to remove the roundness to a square.

Dave

After it's had the slot cut in it, yes.

regards Mark Rand RTFM

Broaching a keyway is the best way and its not that tricky, my father cut keyways for years as a business and although he used a hydraulic press, I have done it myself with a pillar drill or some people call it a drill press. make sure its a really old one so the rack on it is made of proper steel not like the tin plate of today.

Get the broach you need and a set of shims, you can make a guide by turning a piece of bar down to size and then milling a slot along it. Either replace the chuck in the drill with a piece of stock with a flat end of it or put a par in the chuck.and then press the broach through the job. add more shims until the depth is achieved.

Make sure you use some good cutting oil and i would not cut more than a 1/2" keyway like this but it works fine.

I now have an old scrap drill setup as a hand press all the time, had to add an extension to the handles but its great for pushing in bushes, bearing.

Regards

Alastair

On or around Mon, 17 Nov 2008 21:01:54 -0600, "Don Young" enlightened us thusly:

I was about to say that. Depends on the precision required, really.

Interesting as I'm right in the middle of doing this.

I rejected the bush idea - too much extra machining and I'd have had to find some way of transmitting c. 4 HP through it.

I ended up revisiting the method I initially tried and damaged my lathe with, but modified in the light of experience.

Basically, I've ground up a really crude tool, used it very gently to start the slot and align it, then used a bundle of hacksaw blades to take out the bulk of the slot. The final job will involve putting it back into the lathe and using the special tool again to square it up a bit.

It's not the nicest solution and I speak as a lazy bodger with hundreds of similar offences to take into consideration.