1st,& 2nd knurl

[darkzero]

I agree with Mikey. I too try to knurl in the least amount of passes possible to avoid/minimize flaking. I'm usually able to knurl Ti in one pass with my lathe so non-ferrous is no problem either for me.

90% full form is recommended cause it very easy to overshoot 100% depth and as far as functionality for grip, not needed. 100% can be too coarse on the hands for a coarse pitch knurl.

When you overshoot 100% it drastically reduces (damages) the quality of the knurl as it's trying to roll over the peaks. This extra material that gets displaced will roll into the workpiece. It can also damage or reduce the life of the knurling wheels.

With a knurling tool, feed is by eye, there is no dial or a means to measure how much feed on the wheels & the amount to feed varies depending on the work piece diamater & knurling wheel pitch.

Here's one of my first knurls on Ti done with 2 passes. You can see some of the flaking. This type of flaking is usually seen on harder materials. I suppose they can be picked out but would be very time consuming I imagine. As Mikey stated aluminum flakes like crazy but looks different & will usually get rolled into the work piece making it look like crap.

 

[Aukai]

Something else to try....Mikey style

 

[mikey]

Here's one of my first knurls on Ti done with 2 passes. You can see some of the flaking. This type of flaking is usually seen on harder materials. I suppose they can be picked out but would be very time consuming I imagine. As Mikey stated aluminum flakes like crazy but looks different & will usually get rolled into the work piece making it look like crap.

View attachment 313953

I dunno', Will, that looks really good to me. I can see some flakes but it's really minimal.

This is a full pattern knurl. See the sharp peaks? It isn't overdone but it is a full knurl. If this is to be handled by hand it will be sharp so most of us will run a file over the top to take the sharpness off. A 90% knurl will not be as sharp, although I would still make a pass with a file to make it more user friendly. Aukai, this is a very nice knurl.

 

[darkzero]

I dunno', Will, that looks really good to me. I can see some flakes but it's really minimal.

This is a full pattern knurl. See the sharp peaks? It isn't overdone but it is a full knurl. If this is to be handled by hand it will be sharp so most of us will run a file over the top to take the sharpness off. A 90% knurl will not be as sharp, although I would still make a pass with a file to make it more user friendly. Aukai, this is a very nice knurl.

Thanks Mike. Yeah not too bad on the flaking on that one. I wonder if a wire brush would have cleaned it up. But I wasn't happy with it & never used that one, either it's in the scrap bin or I already reused the stock.

That was 1" dia & what I call a medium pitch knurl for the size. Yep too sharp on the hands. The only time I will use a fully formed knurl is for a very fine pitch knurl. They don't feel so sharp & they just look pretty. Lately I have just been doing partial form knurls, not really grippy at all, more for cosmetic I suppose.

 

[mikey]

Yeah, I think after you get used to knurling, that sharp peak thing gets to be a bit much and a partial pattern knurl makes more sense. It's kind of dumb to make sharp peaks and then file them off, right?

 

[mikey]

Here's one for you. It's called a Square Knurl. Any idea how it's made?

 

[darkzero]

I suppose, haha. I guess it's just part of the learning process. We practice to achieve that "perfect" knurl, then when we are happy with what we have done we're at ease. I have done the same except I don't use a file. I'll take a very light skim cut or use emery cloth, same result though.

 

[rwm]

I suppose you could do a straight knurl and then cut circumferential groves?
Robert

 

[darkzero]

Here's one for you. It's called a Square Knurl. Any idea how it's made?

View attachment 313988

I'm not sure but I assume either it was milled or done with a cut knurler. Never looked into it though.

On the flashlight forum some of the guys were making that pattern on flashlight bodies but not nearly as fine as that. They were milled though with an indexer then grooved on the lathe. Sometimes called a frag pattern like on a grenade.

One of my cut knurlers has 15° knurling wheels available in addition to the tool angle that produces a 45° angle knurl instead of the common 30°. But the angle is 45° out from that so still resembles a conventional diamond knurl rather than square (with the peaks machined flat) 90° knurl. Well I think, I don't own any of those knurls.

 

[mikey]

I suppose you could do a straight knurl and then cut circumferential groves?
Robert

Yup, this is how it is done. This is one of Geo. H. Thomas's creations and it produces a grip-friendly knurl that doesn't require filing or sanding. Looks best with fine toothed straight knurls. You have to measure the valley between the peaks and grind a HSS tool to the same angle, then space them the same as the peaks. Cut in the same depth as each valley and you have it.