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ZINOM
03-17-2006, 01:25 AM
I was thinking of getting one of the scissor type knurling tools....maybe from Eaglerock....the only method of knurling I have at the present is an Eaglerock hand knurler (like a c-clamp).

I was wondering if they (that type, not necessarily the brand) work well, I have a lightweight-ish 12" Craftsman lathe....and I don't think I'd be trying to work real hard materials.

I also don't know anything about knurling, I checked a textbook and it didn't seem TOO complex....I'm sure like all things in this hobby, there are complexities to that operation as well.

I was also wondering if the scissor type is meant to travel with the powerfeed....I would hope it would or else I'll just stick with my hand version.

Thanks for the recent help guys, I really appreciate it!


John

Joel
03-17-2006, 01:59 AM
Scissors knurlers work great and yes, you do use the power feed. Knurl at low speed with a fairly fast feed and use lots of oil. As far as technique, I would say to give it a try and see if you have any problems.
If it doesn’t work well for you, do a search. In the archives, you will find that it is easy to always get perfect knurls - and that knurling can hardly be done at all. http://bbs.homeshopmachinist.net//biggrin.gif

debequem
03-17-2006, 05:47 AM
I bought one from Enco (cheap thing) and even I can do it. What I like is that the lathe doesn't take the beating since the work is clamped by the scissor and not by pressing with the slide.

joeby
03-17-2006, 07:21 AM
I have a scissor type, and a 12" Atlas. Works much better than a conventional knurling tool; but be careful with the overhang. If you have an QC toolpost all the better. The scissor type tools are kind of long and put a strain on the Atlas' flimsy top slide if you try to feed too fast.

Kevin

John Stevenson
03-17-2006, 08:01 AM
One point to watch with the sissor type tools is if they have long arms and are not rigid enought and many imports aren't, when you travel down a bar the arms get skewed to the rear and make a mess of the knurl.

Some of the better ones hace a ridgid keep plate on the tailstock side to stop this twisting action.

The longer the arms the worse it is.
I have one here that's only useable on a short knurl where you don't have to travel and it looks well made. It's the leverage and pressure that cause this.


Sir John.

flatlander
03-17-2006, 09:32 AM
I bought one out of Enco's sale flyer and have had pretty good results with it, even on hard SS alloys. I have a QC tool post on a fairly heavy 13x40 lathe. As a rough rule of thumb, I run about half the speed I would run if cutting the work with HSS. As Sir John said, the longer arms are a liability, and the import knurler from Enco has fairly long arms. I squirt a generous amount of WD40 on the work piece & knurls before starting, and keep squirting as long as the knurler is working. WD40 helps cool & lubricate the knurling rolls; it also helps keep any of the metal fines displaced by the rolls from being pressed into the work surface and screwing up the knurl's finish.

JCHannum
03-17-2006, 09:38 AM
Sir John as usual makes a good point.

The Eagle Rock is probably one of the better scissor tools. It is made to do the job, while the imports are made to look like the Eagle Rock. There is a difference.

ZINOM
03-17-2006, 09:58 AM
Excellent input..very helpful, thank you all!

John

johnny o
03-17-2006, 03:35 PM
Hello
I had made this scissor knurl some time ago and use it on my 6" atlas. Evan when it had the bushed head on it, I found it worked quite satiafactory on many jobs.I hope the pic. posted well, its been awhile since I've tried.It's capacity is up to one inch and mounts on a dovetail quick change post.
Thanks:
John http://img.photobucket.com/albums/v211/jore1563/cabinfever2006025.jpg

johnny o
03-17-2006, 03:38 PM
All right guys,I posted a nice pic.(billboard)
I have to knock that down a size next time.
John

Mike Burdick
03-17-2006, 04:21 PM
John,

Excellent work and great finishing details!

debequem
03-17-2006, 06:08 PM
Just keep your fingers away from the knurls!!!!

miker
03-17-2006, 09:28 PM
How do you determine the amount of clamping pressure to apply?

Also a good article on these devices in latest HSM magazine

Michael

Joel
03-17-2006, 10:33 PM
You just add pressure until you get the depth you desire. I usually get the best results when I stop just a bit short of full points. In other words, stop adding pressure when there is still a little bit of a flat spot (although it is not really flat) on the peaks of the knurled points.
Typically, the only trick is to keep the knurls from double tracking.

Nice work johnnie o.

johnny o
03-18-2006, 09:48 AM
I agree with joel, its good to stop just short of a full knurl to allow the spring pressure to unload itself that last little bit and I dont prefer a full diamond pattern anyway just to keep it from being too rough. As for double tracking,sometimes it does and sometimes it don't!!!
Thats it!
Johnny OOOOOO http://bbs.homeshopmachinist.net//biggrin.gif