Knurling

[Dell]

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

 

[cocker]

Did you try different speeds ? And more pressure ?
Is everything locked up good and tight , rigidity is your friend here .
also , is the knurling tool bang on center height ?
I've never used them scissor typ .

 

[Kram]

Easily done. The answer with these pressure/displacement knurlers is to do them up tight. If its too loose the knurl will recut in a different position and give the double or triple tracked result as in your photo. If its tight, it will track the previous rotation. The good thing is your using a scissor knurler, so doing it up tight wont put any excessive pressures on your lathe.

 

[Dell]

Easily done. The answer with these pressure/displacement knurlers is to do them up tight. If its too loose the knurl will recut in a different position and give the double or triple tracked result as in your photo. If its tight, it will track the previous rotation. The good thing is your using a scissor knurler, so doing it up tight wont put any excessive pressures on your lathe.

That’s exactly what I did but I was wondering why the wheels had left and right on them when they are top and bottom could it be that the L should point left & R point to the right in that case putting tool on the back would swap them round.
Dell

 

[Misterg]

I was wondering why the wheels had left and right on them when they are top and bottom

The L and the R refer to the direction of the pattern: left hand or right hand diagonal. You need one of each for a diamond knurl, but it doesn't matter which is which.

It looks like your knurls may not have been running quite square to the work (top to bottom). I had a cheap scissor knurler where the pivots were out of line enough for it to cock over like that. Sometimes, it seems that the knurls 'get off on the wrong foot' and never really recover. Skimming the surface and trying again is my remedy and it often works. (May or may not be related to the pitch of the knurls vs the diameter, but that's verging on a religious discussion.) The initial engagement needs to be very positive - I tighten my scissor knurler up with the wheels slightly off the centre line of the work and advance the cross slide to wedge them more tightly.

Some (possibly) interesting reading:

https://www.doriantool.com/wp-content/uploads/SEC-H-Knurling-Tools_LowRes.pdf