Yeah I'm thinking of that or same on the mill using the quill. I don't want to have to buy broaches. So making something in hss and slowly doing it will probs be my best option.
- Thread starter God mode restorations
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The keyways are already in the shafts, it's the pulley keyways I'm struggling with!
Have a very similar looking TEC motor I mounted recently to a Pollard drill.
The pulley was bored out by a friend, hobbymat I have not big enough.
On advice I used a 8mm dog point screw through the pulley, which I mated into 4mm recess I made in the motor shaft opposite side of the keyway. It's been good, but your application might be more demanding.
If I went belt and braces, I would go steady and just file carefully for the keyway - again on advice - which I might still do.
Thanks for checking. I think they sell mostly King gear. I need to make a door like the one you are doing, and hoping to find a cheaper supplier of the bits than brundel. Cheers
Memmeddu
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That's a good idea it will help to save time.
We use some sort of shaper at work, essentially the same machine but vertical
Use your mill to slot the keyway sideways - leave it round on the top as the key drives on the sides. Assuming you are securing with a socket set screw though the pulley onto the key, the key will remain in place in the shaft well enough.
Pls can you explain, I don't see how I can do it sideways? Thanks.
I think I've worked out what you mean. Rather than plunge, lower the end mill to full depth of the inside of the pulley, then come in from the side. That's not a bad idea. I will probs need a longer end mill though.
Fred Trevvett
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I've never done anything like this, but could you mill slightly 'too deep', so there's less material to remove manually? Like this:
Yellow line is milling pass, then you've only got the two corners in blue to square off. Blue dotted line shows where the base of the key would sit, obviously it's the sides of the key that are taking the load not the base so it doesn't need much contact area, just enough to stop it moving.
Yellow line is milling pass, then you've only got the two corners in blue to square off. Blue dotted line shows where the base of the key would sit, obviously it's the sides of the key that are taking the load not the base so it doesn't need much contact area, just enough to stop it moving.
Theoretically this would be possible, however in reality the long (50mm?) endmill can not cut accurate enough, depending on required quality of work.
The fit on the sides of this type of key determines the service life of the connection. Tigth fit and contact over the full surface area is the best, achieved only with a broach or a file and lots of effort. Milling as proposed can help to remove some material first.
I might spend half an hour making a single point broach out of some 16mm bar with an 8mm hss cutter. Then just one thou cuts. I'm in no rush.
Apologies, poor wording on my behalf - I'm not a machinist! Plunge should do it, as long as you end up with straight sides to the keyway to locate on the key.
If you've got enough material, you don't need to square off, as long as the straight sides locate on the key, and you retain the key with a socket set screw through the pulley hub.
Its not exactly British Standard, but should work okay in this application.
Success with the keyways. Made a broach out of 16mm tool steel. Piece of 8mm hss. Gentle cuts. No side clearance, no top clearance just 7° ish behind cutting edge. I know cast iron is supposed to be cut dry but I used a little cutting oil. One down one to go. Had to bodge a spindle lock!
