Need Keway Broached

lesrhorer said:
Well, OK. How much do you want to do two pulleys, one with a 4mm keyway, and one with a 5mm keyway?
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Cover shipping and a 12 pack (plus include some blueprints), and I can get to it next time I'm in the shop. PM me and I'll send you my address.
 
Well, whew! Spent most of the afternoon getting the first one setup.

I made a plate of aluminum into a holder to put in the vise as a poor-mans angle plate.

I ended up turning a close-fit bar that I could put down the bore, use paper off each side to touch off and use a dial indicator and math to center the tool. I figure the keyway is sub-3 thou centered wise.

I only ground 1 tool for both keys, so it is only .130 wide, which means a bit of back and forth with the dial indicator to cut the whole thing. I fed only 2-3 thou per cut so it got a pretty smooth side.

Then I did a cut across the bottom to clean that up. I got a touch of chatter for some reason at the bottom in 1 spot, but didn't notice until it was off the machine.

Depth and width were cut to exact book-spec, though the key I was given ended up not fitting cleanly. I spent a few moments with a file, and it fits just right. PXL_20210831_224834545.jpg
 

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That is some fine looking work. I would feel bad if it were not for the fact (I hope) you will be able to make good use of the fixtures and tools in the future.
 
lesrhorer said:
That is some fine looking work. I would feel bad if it were not for the fact (I hope) you will be able to make good use of the fixtures and tools in the future.
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:D I like using the shaper, and wanted an excuse to make an internal shaping tool, so this was a good excuse!

Additionally, the mill work for the fixture plate lead to me discovering my mill was miswired! I had a separate thread about that one a few days ago. So multiple good things coming out of this project.
 
I got the pulleys in the mail yesterday and spent the night installing them and machining the idler pulley bracket. Everything works great! The lathe spins up to 3000 RPM quiet as a mouse with almost no vibration.

I want to give a shout-out to Erich for his excellent work on the pulleys. The 45mm bore was perfect. The 19mm bore was just a tenth or so under, which isn't surprising since he did not have the actual shaft to use as a measure. It was close enough I could have pressed it on or heated the pulley, but I want to be able to easily change it in the future if needed. Two minutes with a Dremel sanding drum and it slides on and off with ease. The keys fit easily and smoothly.

It was a real joy working with Erich.
 
Ah shucks! I really thought it was going to be the opposite! I hit the 19mm shaft dimension within about 2 tenths, and was almost 2 thou over on the 45mm bore!

I wonder if the shafts are a little oversized? (Or maybe just my metric to 'Merica conversion was off a touch!).

Either way, glad it worked out for you! I had fun getting the shaper set up for internal keys, it was a fun experience to do on this new shaper. I'd only done it before on a small one.
 
Well, the 45mm fits on a threaded shaft, so if it is .002 or so oversized, it's not at all obvious. I did not measure the run-out, but visually I don't see any. The gear next to it has a lot of axial wobble, so that it touches the pulley on every revolution, so it is far better than the lead screw gears on this lathe. (I will have to do something about that, some day.) I seem to recall the motor shaft was indeed about 0.2 thousandths over when I measured it a few weeks ago.
 
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