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John Stevenson
12-04-2005, 12:12 PM
OK as promised the article on cut knurling.

I bought an incomplete diamond cut knurl tool off Ebay and whist looking for info on this spotted the single wheel cut knurl tools for doing straight knurls.
Did a bit of looking and they looked simple to do so I decided to experiment.
These use a 45 degree knurl set at 45 degrees to cancel the angle out, the reason for this is to give the rotation of the knurl as it moves along the work a shearing action.

First experiment was a piece of square with a recess in it to take the wheel and the shank of the square turned to 5/8" to fit an existing boring bar holder.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/Straight%20knurl1.jpg

The knurl which was bought from J&L has had the front face surface ground to take the chamfer off to give it a cutting edge.
Close up:-

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/Straight%20knurl2.jpg

and results.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/Straight%20examples.jpg

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/Straight%20%20knurl%20tube%202.jpg

This tube is 1-1/2" diameter 16 gauge and it isn't a staged shot, no support and only lightly gripped in the chuck. It it was tightly gripped you would see crush marks, likewise had it had spun you would see skid marks which proves how little cutting forces are needed.

This worked OK and produced a good knurl but it was hard to setup to get the knurl to track in a straight line, it only needed a small amount of twist on the shank to make it track off. What was needed was a method of fine tuning.

This led to the MKII which is similar but built into a dedicated toolholder.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/straight%20knurl1.jpg

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/straight%20knurl2.jpg

Main differences are the shank is held by a pinch bolt on the top, same as a tailstock and the flange just behind the knurl is tapped for two push screws that bear on the lower step to allow the tool to be twisted accurately for tracking.
The fancy knob on the top is the hight adjustment screw for the toolholder but it also carries a spare finer knurl so you don't have to go hunting.

Sir John [ Earl of Sudspumpwater ]

IOWOLF
12-04-2005, 12:18 PM
Um, Sir John, you messed up the Aloris type tool holder is inside out,and therefor will not fit mine and that is the mistake.

------------------
The tame Wolf !

John Stevenson
12-04-2005, 12:49 PM
Done purposely like that so you can't borrow it http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif

Seriously this toolpost or at least the original design was done way back in about 1988 in a period when we had no cheap imports and I had never heard of Aloris.
The onlt QC holders here in the UK were the very expensive Dickerson type.

So I set to and made a toolpost and holders for my Myford ML7 which I had at the time.
I wasn't too worried on the complexity of the toolpost, after all you only make one [ usually http://bbs.homeshopmachinist.net//biggrin.gif ].
What I wanted was a series of holders that were easy to make and milling these with a horizontal mill in a long stick was the easiest for me, the internal dovetail would have been harder to do.

It does have one advantage that I have found and that is the unused slot being internal is better protected from chuck jaws and bumping the tailstock.

Knowing what I know now I would probably go for a copy of the Aloris but with over 50 odd holder between three lathes I'm now committed.

Sir John.

JRouche
12-04-2005, 01:49 PM
I see a rotary table collection? Are those homegrown or store bought? I am in the market for a used Yuasa 8" to convert for CNC but would like to see some you fabbed up if that is the case. Thanks, JRouche

Err, oh yeah, nice knurlin tool.

TGTool
12-04-2005, 04:25 PM
I did a similar tool, cutting the step in the end of a round bar that fits the boring bar holder of the quick change. The clamp screws then let me adjust the wheel so the grooves are horizontal. (Boring bar holder is thus at 90 deg from the normal setup).

Nice pictures of various items, and shop background is a bonus!

JM

Mike Burdick
12-04-2005, 05:28 PM
John,

Does the knurl have a bearing or does it just run on the shank of the socket head cap screw?

John Stevenson
12-04-2005, 05:45 PM
The knurl which obviously is hard runs on a top hatted stepped bush made from drill rod and hardened right out, no tempering.
The screw traps this in position. The step portion is larger in length by a few thou than the knurl to allow it to spin but have a secure spindle.

I chose this type of recessed knurl as they have a larger hole to accet such a bearing and you can get closer with it being recessed.

If you can control end float there is no reason why you can't use a conventional plain knurl but again you need to surface grind the face to get a sharp edge.

JRouche,
The Rotary tables are commercial units I convert as a job, I don't sell these or have any control over them.

I have converted many in the past see
http://www.divisionmaster.com/
Examples of use.
The 6" Vertex, pic's No. 2,3,4
The BS1 Dividing head pic 6
The 5C spin indexer pic 8 and the large Hoffman D/H pic's 16,17 and 18 are all my tables/heads that tony has used in his web page.

Sir John.

J Tiers
12-04-2005, 06:01 PM
I like it......

I think even I could probably do a good deep knurl with that setup.....

Most setups make me feel like I am springing the whole lathe. And that's a reasonably heavy Logan, not a real lightweight.

Fair warning..... I intend to shamelessly copy the setup.

John Stevenson
12-04-2005, 06:02 PM
<font face="Verdana, Arial" size="2">Originally posted by J Tiers:
I like it......


Fair warning..... I intend to shamelessly copy the setup.

</font>

That's the whole idea of me posting here.

John S.

Mcgyver
12-04-2005, 09:21 PM
<font face="Verdana, Arial" size="2">Originally posted by John Stevenson:
If you can control end float there is no reason why you can't use a conventional plain knurl but again you need to surface grind the face to get a sharp edge.
.</font>


John, thanks very much for sharing all of this know-how.

Would I be correct in assuming that why would controlling the end float is an issue with a conventional plain knurl that when you sharpen in you changed the float? too bad, I have some plain knurling wheels.

if you held straight knurls at a 45 angle, could you similarly cut diamond knurl or is it not that simple?

lugnut
12-04-2005, 10:44 PM
Sir John, THANK YOU
Mel

John Stevenson
12-05-2005, 03:32 AM
<font face="Verdana, Arial" size="2">Originally posted by Mcgyver:


If you held straight knurls at a 45 angle, could you similarly cut diamond knurl or is it not that simple?</font>

No, not that simple unfortunately.
If you did this you would just one side of a diamond knurl, right or left depending on the angle you held it +45 or -45.

I got into this cut knurling after buying an incomplete diamond knurl tool off ebay.
These are quite complex as the wheels meet the work below and above centre. Because of this and beacuse they are at an angle the knurl wheel only lies flat on the work at one diameter.
To get by this the axles can tilt so the wheels lie flat at any given diameter.

The fact that the axles are tilted anyway and the adjustment tilt which is in a different plane makes these hard to understand and duplicate.
I'll take a picture later as it will show it better.
If you don't get the adjustment correct it doesn't meet the work on the front edge and so it doesn't cut.
If you get too much front tilt it cuts but the knurl is not symetrical and comes out elongated in the vertical.

Sorry for sounding so vague but it's hard to explain in words.

Sir John.

Evan
12-05-2005, 09:59 AM
Damnit John, the last thing I need is another project. I even have a pair of straight knurls laying about that don't fit my knurling tools. Now I will be forced to think about using them every time I see them in that drawer.

Maybe if I move them it will help...

John Stevenson
12-05-2005, 10:09 AM
<font face="Verdana, Arial" size="2">Originally posted by Evan:
Damnit John, the last thing I need is another project. I even have a pair of straight knurls laying about that don't fit my knurling tools. Now I will be forced to think about using them every time I see them in that drawer.

Maybe if I move them it will help...</font>


Perhaps if I sent you the pic's of the diamond tool..............................

Sir John.