MadModder

The Shop => Tools => Topic started by: Dell on March 12, 2024, 11:50:03 AM

Title: Knurling
Post by: Dell on March 12, 2024, 11:50:03 AM

I made a couple of knurled knobs but when knurling them I couldn’t get a very nice knurl , I couldn’t get knurling very deep and it was better on both outer edges but the middle of the knurl was rubbish , I have a scissors type tool in the rear tool post on my Myford 10, the shorter one I am very happy with and was done some time ago from the front but the longer one I made today using same tool but from the rear, I thought maybe the knurles were the wrong way round so turned then over but I didn’t try moving bottom one up top and top on bottom could that be the problem?
Dell
 

Title: Re: Knurling
Post by: RussellT on March 12, 2024, 12:47:43 PM

I don't think it matters which way around the knurls are.

I start with the knurl quite loose to establish a bit of a pattern and then tighten the clamp up to make the pattern deeper.  The clamp has to be properly on top and bottom of the work otherwise it'll be pushed away from the work.  Oil helps.  Some people say you have to get the diameter right so there's an exact number of knurl patterns.  I haven't found that to be the case.

Russell

Title: Re: Knurling
Post by: Dell on March 12, 2024, 12:52:48 PM

I ran slow with tool on centre and added pressure by tightening adjuster with oil.
Dell

Title: Re: Knurling
Post by: Joules on March 14, 2024, 06:59:10 AM

The knurls never bit down hard enough, what is your material and has it work hardened ?

Another point, were the knurls clean of swarf, metal particles.

Title: Re: Knurling
Post by: Dell on March 16, 2024, 07:20:16 AM

 

Quote from: Joules on March 14, 2024, 06:59:10 AM

The knurls never bit down hard enough, what is your material and has it work hardened ?

Another point, were the knurls clean of swarf, metal particles.

The Steel is EN1 mild bright I cleaned everything before hand and used lots of oil , I am wondering it moving tool to the rear made the difference because I had to take everything apart and put it back together the other way round otherwise the adjuster would have been on the bottom and impossible to adjust.
Dell

Title: Re: Knurling
Post by: RussellT on March 16, 2024, 08:41:59 AM

I don't see how that could make any difference.  I don't really see why the tool would have been upside down either - I think even when used in a rear tool post it would be fine to run the lathe forward so the tool could still be the right way up.

You have made me wonder though if there is any possibility of misalignment between the knurls.  If they were able to move sideways or the points of the diamond pattern were out of line then that might cause a problem.

I assume you are using diamond knurls?  You can do a diamond pattern with straight knurls at 45 degrees.

Russell

Title: Re: Knurling
Post by: Joules on March 17, 2024, 08:08:59 AM

A couple of pictures of your knurling tool in situe, showing alignment and one with a bit of stock between knurls before knurling.