Looking for tips on scissors knurling.

Thanks for the compliment @woodchucker! As I was just trying I didn’t bother trying to figure out the diameter to pitch. I must of got lucky enough. Is there any recommendations for feed speeds? I’m thinking that the slower you go the more re-forming/cutting that’s happening?

Also I set the tool square to the work. When feeding you could see it flex away from the headstock. Does everyone set it that way or should I be competing for that but rotating it a little bit towards the headstock?
 
Thanks for the compliment @woodchucker! As I was just trying I didn’t bother trying to figure out the diameter to pitch. I must of got lucky enough. Is there any recommendations for feed speeds? I’m thinking that the slower you go the more re-forming/cutting that’s happening?

Also I set the tool square to the work. When feeding you could see it flex away from the headstock. Does everyone set it that way or should I be competing for that but rotating it a little bit towards the headstock?
For a scissor type it should be 90 to the stock (MOSTLY), that doesn't mean you can't try to get special effects by skewing it. Everything you do to learn what happens when you do adds to your knowledge, and in this case saying never is just not a good idea. Everything has to be considered.
So 90 is the goal.. but learn what happens when you turn it off 90. Yea, you'll go through stock, but you may learn something. If your knurl is ever giving you problems, maybe your testing will show you something that helps you troubleshoot.

Hints while knurling:
Don't use a brush, most of the time it will get sucked in and cause issues.
Use an oiler or squirt bottle.

Go slow, you are doing a lot of form cutting, and it's tough on small lathes.

Keep flooding it. I've never heard of too much cutting fluid.

Try too much pressure, you will see why, and need to recognize it when you have done it.

I looked up the thread that Will @darkzero did on knurling. Take a look. These were pretty in Titanium.:
 
I'm in the camp of knurling in one pass/least amount of passes if possible. I also calculate for diameters although with soft materials like aluminum it's not really necessary all the time.
 
While I use machining math many times every time I get in my workshop, I react to links to math calculations like a 12 year old. “Aw, man, I don’t want to do math!“ The link to the knurling math was enlightening and once the pitch is calculated it’s very easy.

I haven’t made a nice knurl yet with a new knurling tool that came with a Bostar QCTP set. Never had a problem with my old one which is American made. The information in the link made me realize that the Bostar knurler probably has a metric pitch. It’s also one of those with fixed wheels so it has to be centered perfectly. The old one pivots so perfect centering isn’t critical. Got to try it out again and do the math for both of them.
 
Here is another site link to a knurling calculator for a cheating math guy.

My boss and I have just started talking about this very topic for a possible job.



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One pass, using oil or water soluble coolant. With aluminum, the grade and type does matter as far as machinability. Difficult to pick up knurl for cumulative passes in production .
Not necessary for a production machine or commercial lathe.

You use the leadscrew and the reversing function and never disengage the tool.
 
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