Author Topic: Cutting keyways without a broach.  (Read 2149 times)

Offline Jasonb

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Re: Cutting keyways without a broach.
« Reply #15 on: December 24, 2017, 01:33:41 PM »
More than likely it will in this case so give it a go.

When it comes to making the key leave it on the end of a length of bar while you fit it as that makes it easier to pull out.


Offline Alyn Foundry

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Re: Cutting keyways without a broach.
« Reply #16 on: December 24, 2017, 01:56:55 PM »
Hi Peter.

Seasons greetings.

Your tapered key in a parallel key way will only “ bite “ at the point of contact.

It would be better to place a packer behind the back of the flywheel and broach/slot a tapered way through the boss.

I remember years ago restoring an EEC gas engine for a customer, this engine had been fitted with taper pins instead of the usual gib head key and way. It was a rather neat way of fixture, I’ve never seen it done on anything since!

Cheers Graham.

Online Gas_mantle

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Re: Cutting keyways without a broach.
« Reply #17 on: December 24, 2017, 02:16:01 PM »
Hmm, I think it's time for some of this  :DrinkPint:  to help me think about it  :)

Offline pgp001

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Re: Cutting keyways without a broach.
« Reply #18 on: December 24, 2017, 05:05:45 PM »
Peter

I have a 1/16" broach and the bush to fit a 5/16 hole which would probably be OK for an 8mm, I could put the keyway in for you.

Phil

Online Gas_mantle

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Re: Cutting keyways without a broach.
« Reply #19 on: December 24, 2017, 05:38:51 PM »
Thanks Phil, that maybe something I'll take you up on  :)

I would like a set of broaches but they are expensive for the limited use I need so I can't really justify the cost.

Happy Christmas and thanks for your help.

Offline Alyn Foundry

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Re: Cutting keyways without a broach.
« Reply #20 on: December 24, 2017, 06:24:33 PM »


I would like a set of broaches but they are expensive for the limited use I need so I can't really justify the cost.

Happy Christmas and thanks for your help.

Hi Peter.

Whilst I agree with your sentiments a couple of broaches of the sizes needed in most ME applications has done me for well over 35 years and they’re still ready for the next engine.

All the best, Graham.

Offline Bobsmodels

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Re: Cutting keyways without a broach.
« Reply #21 on: December 24, 2017, 10:22:17 PM »
Hi

I finally made up a set of tapered sleeves for the broaches I had.  I have attached a file showing how I made a Master block.  It was then used to cut the angle in sleeve and make keys.  The only critical dimension is 1/8" in 12" taper.  Even that is not critical, just get your Master close and make everything using the Master block and all will fit together.

I got tired of always making do especially since I was going to making more flywheel engines.

Enjoy

Bob

Offline 10KPete

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Re: Cutting keyways without a broach.
« Reply #22 on: December 24, 2017, 10:27:21 PM »
I've always wanted a 'set' of broaches but the cost is prohibitive. So I have three small size ones that do all the model size stuff and I make a bush when needed.

I don't find I want a 'set' anymore! Not runnin' a job shop here.....

Pete
Craftsman, Tinkerer, Curious Person.
Retired, finally!
SB 10K lathe, Benchmaster mill. And stuff.