knurling

[Vinny]

I haven't knurled in over 40 years. I have a piece of 12L14 that I've already turned down to what my knurling tool needs. I'm all set and ready to run but I have one problem. Like I said, I haven't knurled in over 40 years. I remember it's done in back gear in slow speed. How slow???

[DaveH]

I assume we are talking 'bump' (pressure, force) knurling and not the cut knurling.
I do it at 90 rpm because that is as slow my lathe will go, slower may be better (40 rpm)
If you have force flood coolant that will be good to flush away the chips. If you don't have any force flood coolant then here's my little secret.
This will be our secret so don't go and tell everyone   
You will need a hard small brush a small brass or steel one and as the knurling starts brush as hard and as fast as you can to get rid of all the little chips. Chips from the work piece and the knurls.  This stops the little bits getting embedded into the work piece gives a better knurl.

Now be careful - don't get the brush caught up it will wreck your knurling, your knurling tool and your nerves. So be careful it can be quite scary when it happens - I know from experience  
 
DaveH

[Vinny]

I had already planned on 30 RPM since that's the slowest speed. What I don't remember is the carriage speed. And yes, bump knurling. Good idea, our little secret!

edit: after re-reading my original post I see I was as clear as mud wrt speed!

[DaveH]

(10-28-2015, 04:27 PM)Vinny Wrote:   What I don't remember is the carriage speed.  

I've only moved the carriage manually - slow and I sort of "notch" it along with one hand a bit at a time ....... the hard brush is in the other hand
I sort of feel it.
Hope that helps 

DaveH

[Roadracer_Al]

And LOTS of oil.

[Vinny]

SUCCESS!!!!!

I opted for 32 TPI and it seemed right.

So, oil can in one hand, brush in the other and we have this


One note, the reddish or stringy stuff you see are from the molting HF shop rag I used to sop up some of the oil left on it.

The line in the middle is my cut line. It's going to be two handles.

[DaveH]

Wow that looks good  
 
DaveH

[wawoodman]

Not too shabby!

[Vinny]

Thanks guys! I just posted the finished project in the "what did you do today" project thread.

[Mayhem]

Nice knurling there Vinny.