Which knurling tool?

[raynerd]

Hi guys, despite being in this hobby for near 4 years now, I've never owned or used a knurling tool. There are a number of neat threads on this forum covering this topic, but quite a lot of the threads discuss home made cutters. I'm looking to purchase a commercial cutter and curious if anyone had any recommendations.

I'll be using it in the boxford for now although if I could fit it to the small Cowells all the better.  I know size is a consideration but if I get a bigger one does that mean I can get smaller work in it as well, or do I need a couple of sizes in the long run? Also, I appreciate that the disks produce the different patterns so it would probably be good to get a set of a few different wheels.

Any recommendations would be welcomed. My reading so far seems to infer that these clamp style ones are "best".

Chris

[andyf]

Hi Chris,

The clamp type is better for your spindle bearings than a "bump knurler", which is simply pushed into the side of the work with the cross slide. The floating pincer movement of the clamp type exerts equal pressure top and bottom, which is better on smallish lathes, though your Boxford might not mind bump knurling.

I bought mine from Warco at one of the shows, and think it's the second one shown about  halfway down here http://www.warco.co.uk/132-knurling-centres-die-holders . The arms can be attached to the inner or outer holes on the frame, so it will cope from very small diameters up to about 35-40mm. I have used it in part bump, part clamp mode on a 50mm diameter, but that was in softish aluminium.

It's too big for your Cowells; you couldn't get the cross-slide far enough out to get the knurls to straddle your work, and the shank which goes in the toolpost is 10mm square.

Andy

[Jonny]

Depends what you want to do and if times on your side or want a better job no set up and done quicker with a more useable tool.

Clamp style the constant setting up for each diameter just for a one off would be deemed for the scrap pile upon first use. The only advantage they would have there is long deflecting work. Then theyre only any good for cylindrical knurling, cant do large diameter front faces or tapers just the edges.
Change of knurl pattern means changing the two wheels over.

[raynerd]

Cheers Andy. Will look up that one when I`m fresh tomorrow and can read properly. Currently rocking baby to sleep and am half alseep myself.

Jonny: Can you please explain what you mean by this as I don`t understand what you mean by setting up?? My understanding is that there was no setup as such and you simply start the work turning and slowly screw up the clamp onto your bar until you are happy with the knurl. That said, I haven`t used one so please do put me right!   

"Clamp style the constant setting up for each diameter just for a one off would be deemed for the scrap pile upon first use.

[awemawson]

Chris,

Definitively use the clamp style on your small lathes or you will b*****r the headstock bearings in no time at all. The plain 'feed in' style apply enormous radial forces where as the clamp style mainly contain the stress within the clamp arrangement.

As for constant adjustment, I've seen pages written on the correct mathematical relationship between blank diameter, knurl diameter and depth, but in practice over more years than I care to remember I've adopted the following with excellent results: set lathe rotating very slowly, bring the clamp knurl over the work so that the knurl centres are in line with the stock centre. Slowly adjust the clamp until the knurl starts to form then traverse the width of the work by hand, re-traverse several times tightening the knurl as you go until you have the depth you want. If hard stock use copious oil. Takes far longer to write than do!

[Stilldrillin]

Chris.
Wot Andy sed! 

Just work it gently, until it looks right......

David D

[RussellT]

If you use the clamp type you can do diamond patterns with straight knurling wheels by setting it up at 45 degrees.

[sshire]

Chris
Mine is from Hemngway Kits. It's not only nicer than most I could buy, but it was quite easy to build
And does a fine job.

[John Rudd]

use the clamp style

Yup, I also use a clamp style to great effect..

[Jonny]

Thats just it, got to continually keep winding in or out to match the diameter.

No body heard of a tailstock?

[Stilldrillin]

Thats just it, got to continually keep winding in or out to match the diameter.

No body heard of a tailstock?

Jonny.

We've all heard of pifflin' headstock bearings, in lightweight lathes.......

David D

[Meldonmech]

The normal convention in clock making is to make components having a straight knurled finish, it would be shame if after spending many hours building a fine clock to have it frowned on by the traditionalists, if this is something you already know please ignore my comments.
                                                 Cheers David

[minerva]

Chris,
for my two penn'oth.
I have two knurling  tools , the first acquired from ArcTrade Euro :  item 060-330-00100 a   12mm Clamp Type Knurling Tool priced at £24.00  this tool is used frequently on my Real Bull 7x12 and performs extremely well. The second unit was acquired from Hemingway Kits when I first recognised  a tool that I first used in my apprenticeship day over 50 years ago the unit concerned permits control over the knurling process utilising a cam motion to control the knurling depth. This is useful where a batch of components need a consistent knurl. The tool is straightforward to manufacture over say a weekend  and is a useful exercise in tool making.
Regards
Terry T