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shedhappens
25th August 2012, 05:29 PM
I had to do keyways in 4 aluminum pulleys today, I didn't know whether or not this had been mentioned in here so I took a some photo's for those that might be interested.

I hadn't done it this way before, I could have used a mate's keyway broach except for some reason, that I don't know why, when I cut the keyways in the shafts I didn't cut them deep enough, I wanted a 1/4' keyway but the keyway depth in the shafts was only 0.111" and should have been 0.125" or there about's ?

So I thought it wouldn't hurt to have a bit more of the key in the aluminum pulley anyway and the keyway broach might not cut deep enough so I cut the keyways in the lathe.

Depth of cut seemed to be the sweetest at about 0.0025" but I soon found that I had to back the tool out of the cut on the back stroke as I chipped it.

I suppose that because I am blind as a bat that I had a bit of trouble getting the tool height right, but every time I save up some moola to buy a proper pair of spec's I have to pay a bill or buy a new tool.

It was the best I could do with the photo's :oo:

John

pipeclay
25th August 2012, 06:08 PM
How deep did you set your cutter when cutting the keyway in the shaft?

shedhappens
25th August 2012, 06:19 PM
obviously 0.111"

maybe I mucked up my conversion to metric, as I said I don't know, I cut those keyways 6 or 9 mths ago,

pipeclay
25th August 2012, 08:10 PM
Not really obvious,where did you measure your depth from,did you allow for the radious of material.

Ueee
25th August 2012, 08:19 PM
when I cut the keyways in the shafts I didn't cut them deep enough, I wanted a 1/4' keyway but the keyway depth in the shafts was only 0.111"


Seems pretty obvious to me.....
Nice work John, just think, once the Austolite is up and running you could cut keyways all day long just for fun:D

bwal74
25th August 2012, 08:33 PM
Hi John,

I was just going to say, That's a job a for a shaper! But Ewan beat me to it.

Nice job though.

Ben

shedhappens
25th August 2012, 09:03 PM
Not really obvious,where did you measure your depth from,did you allow for the radious of material.

The possibilities are endless pipeclay, the most likely is that when I touched the slot drill on the top of the shaft I only THOUGHT that I seen a witness mark :C and I then zeroed in the dial on the Z axis 0.014" above the job and that may account for the lack of depth :q

Then again I might have had too many beers :U

Or........ it might have been one of my rough days :no:

dunno, don't care

simonl
25th August 2012, 09:43 PM
Hi John,

So let me get this straight, you use a boring bar and set it at centre height and perpendicular to the job, set it approx. 2.5 thou into the job and simply drag the cutter through the pulley. Assume you clamp the spindle? So effectively using the lathe saddle as the moving part on a shaper, just with much light cuts?

Good work. Beats using a file which is what I last did on a flywheel!

Simon

pipeclay
25th August 2012, 09:44 PM
Not much a of an attitude,hope that dosent flow across into other things you make.

shedhappens
25th August 2012, 10:43 PM
Hi John,

So let me get this straight, you use a boring bar and set it at centre height and perpendicular to the job, set it approx. 2.5 thou into the job and simply drag the cutter through the pulley. Assume you clamp the spindle? So effectively using the lathe saddle as the moving part on a shaper, just with much light cuts?

Good work. Beats using a file which is what I last did on a flywheel!

Simon

Simon I had the lathe in low gear that's all, the chuck moving was not a problem anyway, it didn't budge when pushing the tool through.

shedhappens
25th August 2012, 10:45 PM
Not much a of an attitude,hope that dosent flow across into other things you make.


pipeclay, next time I do a keyway on a pulley that will rotate at the incredulous speed of 0 - 60 RPM with a massive torque of maybe 10 foot pounds I will ensure that the utmost care and precision is undertaken, health and safety issues are adhered to, and I will even get the thing platinum plated especially for you.

Attitude, you should ponder that word.

Clubman7
25th August 2012, 10:54 PM
Good job.
Have done this method which is like broaching really.
Gets the result and with care is just as accurate.

pipeclay
25th August 2012, 11:24 PM
If the pulley is virtually unload why go to the trouble of cutting a keyway to an extra depth,when you could of just broached it and machined or ground the key to suit.
My attitude towards most people is the same,give them the respect I beliieve they deserve or earn.

shedhappens
26th August 2012, 12:11 AM
I'm really getting sick of your pathetic questions pipeclay.

I have seen you do this arrogant form of nit picking to other people and as far as I'm concerned you can go and jump.

why didn't you do this

why didn't you do that

you sound like a nagging woman

Steamwhisperer
26th August 2012, 12:14 AM
HI John,
I have lost count of how many keyways I have cut in the lathe. Successfully as well. So many I went out and bought a broach kit. You could have made more shims to go behind the broach to bring it out more...assuming you have the broach still:)
With regard to the Peter (Pipeclay), he is a very learned gentleman with regard to gearcutting and all things Hercus but as I have found out on a previous occasion, he will keep this going ad nauseum. I also found out you will have to be the one to just forget about it and stop responding. I have no idea why he does this. I'm sure we don't need aggravation like this here.

Phil

shedhappens
26th August 2012, 12:19 AM
Thanks Steamie, :U

Big Shed
26th August 2012, 09:56 AM
Not much a of an attitude,hope that dosent flow across into other things you make.

Pipeclay, please confine yourself to positive contributions to this forum, any further nit-picking posts will be moderated.