How to Knurl ???

[jtice]

I have yet to attempt to knurl anything yet on my lathe.
I wanted to get some pointers here first. (man I love this MMM section)

I think I get the general idea, but there seems to be a few odd things I am not sure of.
I assume the knurlers wheels should be positioned directly above, and below the piece?
And then tightened down onto the peice so its pretty snug?

Heres the things I dont get.
1) How do I move the knurler down the piece? Is there a threading setting I should be using?
I cant just hand crank it, cuz then the knurling would turn out all weird, and not spaced out right.

2) Wouldnt the knurling look different for each diameter piece?
A larger dia. would mean it would take more rotaions of the knurler wheels to go around the piece.
If thats true then, wouldnt there really need to be a certain dia and patern knurler wheel for each dia piece?
The grooves on the knurler would have to be spaced out just right so that the groove rolls back over the first groove it made.
If not, it would never be grooving in the same spot, and just,,, well it up the piece.

I just dont understand how I am supposed to get a nice even fairly deep knurling.
Especially when going down the lingth of a body for example.

Thanks for the help guys.

 

[Chief_Wiggum]

Ahh, I'm in the process of making a knurling tutorial. I'll get it done today, just for you /ubbthreads/images/graemlins/grin.gif

To answer your questions:

Yes, position the knurlers directly above and below the piece. Tighten as tight as you can.

1) I hand crank. Surprisingly it works fine, because once you start the knurling, the wheels stay in their tracks. You need to go slow so as you crank the the wheels follow the pattern they just made.

2) Yes. You need to turn the piece down to a diameter that's an even multiple of the pitch of the teeth on the wheel /ubbthreads/images/graemlins/wink.gif I put up a web page calculator to do it for you:

http://www.myrolypoly.com/users/Taig/knurl_calc.php

So if your 0.750" diameter wheels have 75 teeth, then the wheel has 100 teeth/inch (tpi). The distance between the teeth is the 1 / tpi = 1 / 75 = 0.013" The starting diameter of the piece needs to be x * 0.013" where x is some integer value.

That's the basics. Unfortunately, in practice I've found knurling to be one of the most frustrating operations to perform on the lathe.

I'll post in the tutorial how I've been getting great knurling almost every time.

 

[cy]

Thank you!!!! looking forward to your tutorial

I LOVE this new section. This forum is answering most of the questions I've had stored up.

 

[jtice]

Mike,

Wow, thanks alot!
Cant wait to see the tutorial, that sounds great.

You answered alot of what I was wondering though, thanks.

I am just so scared of ruinning a part I spent hours on.
Gonna have to do alot of practive knurling first.

 

[Chief_Wiggum]

I always knurl FIRST. That way when I screw it up, it doesn't hurt so bad /ubbthreads/images/graemlins/grin.gif