Talk:Knurling

adding new section

This article needs some edits. I can do it when agreed. It is mentioned in this article, "On the lathe, knurl cutting is usually accomplished using the same automatic-feed mechanisms that are used to cut screw threads;" Do we cut anything in knurling? Do we get some cutting waste out of this process. If not then let me do the edit. —Preceding unsigned comment added by Altafqadir (talk • contribs) 15:22, 2 June 2009 (UTC)

Re rolled knurls Though the picture shows a knurling tool with two rollers this is only one sort. The other sort has two roller that are clamped on opposite sides of the workpiece. This means the force used is not against the headstock bearings or the cross-slide nut. Furthermore the force used can be much greater. If enough pressure is used a knurl can be made on any diameter of workpiece. When doing this the workpiece and the rollers on the knurling tool should be well lubricated. Where the knurl needed is wider than the knurling tool only a very light force should be applied. The tool is then moved across the workpiece, then the force is increased and so on till the required knurl is achieved. A knurl made like this produces some dust and the result is larger in diameter than the original piece of metal. It would seem to me that most of what happens is the metal is squashed into shape. When the knurl is finished it always looks better if the end of it is chamfered. On a long knurl 45 degrees looks ok but on a short knurl 60 degrees looks better. 81.100.167.66 (talk) 10:47, 28 January 2010 (UTC)

History

Historically, how long have knurls been around? I have a knob from the early 1900's that has been knurled... —Preceding unsigned comment added by Wikimvn1 (talk • contribs) 17:32, 7 October 2010 (UTC)

(it's another person writing)

i can deffenitily assure you that knurkling has been around since the second part of the XVIII centurie. The designs on it became more an more complicated with time until the end of the XIX when we started to loose the knowledge of it's making. Many artisan still have many of them but we live on limited suplies of conplicaed designs, since once you ruin one, it's gone forever and no one knows how to make them. But I do know a fellow metal spinner who is taking great interest in it and might find the way to do it again.82.226.87.88 (talk) 21:06, 19 September 2017 (UTC)

Rolled Knurls

The following section is a popular myth but complete nonsense:

Rolled knurls are somewhat more complicated to design than cut knurls because the outer diameter of the work piece must be chosen to allow the roller to roll an integral number of patterns around the workpiece. By comparison, for cut knurls, the spacing of the cuts is not preset and can be adjusted to allow an integral number of patterns around the workpiece no matter what the diameter of the workpiece.

The difference in the number of patterns around the workpiece at the spacing of the knurl differs by three between top and bottom of the impressions. As long as the knurl is presented so it makes an adequately deep cut it will self-align and cut an integer number of knurls regardless of diameter. Stub Mandrel (talk) 11:33, 19 August 2016 (UTC)

I have changed the text. The explanation is simple:

A typical knurl has a depth of about 0.6 the knurl pitch. The circumference of the cutter will be 0.6 x pi = ~2 knurls greater at the tips of the pattern as at the roots. The opposite applies to the pattern on the work, so the 'correct circumference' is four steps larger at the tip as at the base of the pattern, in practice the knurl will self align rapidly.

Another way of looking at this is that the cutter needs to be move inwards by ~0.5 knurl height (as some extrusion takes place as well as cutting) during the cut. The effective circumference of the cut decreases by about 1.5 knurls as this happens. Only with a very timid approach and great luck is it possible to maintain a double pattern without the knurls self aligning during this process.

Stub Mandrel (talk) 14:27, 29 September 2016 (UTC)