Guys,I am down to just the knurling part of my knobs which has me very nervous at this point.Looking for some tips that will put things in my favor since there's alot working against me.Any pointers,advice that you can give other than "don't try it"?I have watch several utubes on how to figure the OD to get it as close as can be so that's a plus.Thanks for the help
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Tips For Knurling Stainless Steel
- Thread starter Kroll
- Start date
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- Sep 29, 2014
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What kind of tool and knurls will you be using?
A cut knurl will require the least amount of force.
A cut knurl will require the least amount of force.
That would be good information to know,dang my memory.Anyway thanks for asking,I have one of those scissor knurling tool Eagle Rock which I just purchase a set of wheels from Accu-Trak that are the 30TPI RH/LH type which I hope is the diamond pattern(think its called)When I order the wheels I told them that I am trying to knurl SS so this is what they suggested.I know nothing about knurling,this will be my first time
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- Sep 29, 2014
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I have used one of the Eagle Rock tools.
Like any form knurling tool with 2 knurls run them onto the part as fast as you can, on a CNC lathe I feed the tool into the work at .025" Per Revolution, I believe that Eagle Rock reccomends more then that, on a manual lathe a cross feed stop would be a good idea but not necessary. Run the feed in as fast as you can until it hits fairly hard then move it a bit more. If you go to far the backlash in the lead screw will cause the knurls to pass center and pull the cross slide with them, knurling takes a great deal of force.
This is a test piece with the eagle Rock tool, 1/2" 304 SS, I ran the part the same way and it double tracked so I had to make another part, it worked just like the test the second time, go figure.
I work in a fair sized machine shop so we have thousands of pounds of drops lying around.
Good luck
Like any form knurling tool with 2 knurls run them onto the part as fast as you can, on a CNC lathe I feed the tool into the work at .025" Per Revolution, I believe that Eagle Rock reccomends more then that, on a manual lathe a cross feed stop would be a good idea but not necessary. Run the feed in as fast as you can until it hits fairly hard then move it a bit more. If you go to far the backlash in the lead screw will cause the knurls to pass center and pull the cross slide with them, knurling takes a great deal of force.
This is a test piece with the eagle Rock tool, 1/2" 304 SS, I ran the part the same way and it double tracked so I had to make another part, it worked just like the test the second time, go figure.
I work in a fair sized machine shop so we have thousands of pounds of drops lying around.
Good luck
- Joined
- Jul 9, 2014
- Messages
- 613
I've not done knurling for almost 50 years , my memory dims with time and health in general .
Is there a formula for knurling a known recommended diameter ? ( Any lists / charts on line ??? )
On the knurling wheels do the engraved numbers indicate such a related formula ?
Is knurling best done between centres or the chuck and a live centre point or would the live centre point get in the way ?
Is there a formula for knurling a known recommended diameter ? ( Any lists / charts on line ??? )
On the knurling wheels do the engraved numbers indicate such a related formula ?
Is knurling best done between centres or the chuck and a live centre point or would the live centre point get in the way ?
I found a chart on Utube which I downloaded,even after using it to come up with a correct OD I still think that I am doing it wrong.My knurling just don't look right.Wreck/Wreak I read your post couple of times and I don't understand which means I don't know if I'm doing it correct or not,I have never in my hobbist life done any knurling until this weekend.Anyway let me explain and please correct me,my eagle rock is the scissor type which I move it over the part (top/bottom) on center.I turn on the lathe and turn the nut down till it tight and make a pass using hand feed.After one pass I turn the nut a 1/4 turn then make another pass in the opposite direction which after the second pass I call it good cause I don't know either way.If I find my camera I am going to post some pics.----Carroll
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- Sep 29, 2014
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Did you get the instructions that came with the tool? If so follow them.
If not.
In brief, square the tool (in practice on a small hobby type lathe you may have to set it out of square to offset any flex in the machine) put the knurls as close to the X axis centerline as possible and note the dial position.
Tighten the scissor screw by hand until the knurls touch the work then back off the cross slide, turn the adjusting nut 1/4 or more turns, turn the spindle on and run the cross slide in to center as fast as you dare, feed to length. You may want to let it dwell at the beginning and end. Trying to pick up the pattern for a second pass rarely works well.
Knurling is more of an art then a science, I have never met a single person in the business that likes it, they usually give it to me in this shop because I'm the one whom dislikes it the least (-:
Disclaimer: I do this for a living and have an estimated job time to meet which rarely gives time for screwing around doing tests, I am expected to get it right the first time, every time.
If not.
In brief, square the tool (in practice on a small hobby type lathe you may have to set it out of square to offset any flex in the machine) put the knurls as close to the X axis centerline as possible and note the dial position.
Tighten the scissor screw by hand until the knurls touch the work then back off the cross slide, turn the adjusting nut 1/4 or more turns, turn the spindle on and run the cross slide in to center as fast as you dare, feed to length. You may want to let it dwell at the beginning and end. Trying to pick up the pattern for a second pass rarely works well.
Knurling is more of an art then a science, I have never met a single person in the business that likes it, they usually give it to me in this shop because I'm the one whom dislikes it the least (-:
Disclaimer: I do this for a living and have an estimated job time to meet which rarely gives time for screwing around doing tests, I am expected to get it right the first time, every time.
Thanks Wreck,I now understand how to go about the setup.Will give it a shot,quick question on diameter.Using the information that I found on the net for 30tpi wheels I come up with .742 dia for the perfect knurl but mine is far from it.Then I also read other post not to worry about the diameter that does not matter and will look just fine well it don't.Any advice on the OD on how to figure the size?
My wheels I purchase from AccuTrak,they are the ones that are convex in shape,but when I am knurling I am getting shavings which I read that the tops of the diamonds is being cut off.What is the TPI on the one that you did in previous post
My wheels I purchase from AccuTrak,they are the ones that are convex in shape,but when I am knurling I am getting shavings which I read that the tops of the diamonds is being cut off.What is the TPI on the one that you did in previous post
- Joined
- Sep 29, 2014
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- 2,102
Can't help you with the diameter as I have always had to knurl the parts at the specified diameters on drawings. That being said the diameter is probably less important then the process being employed and the machine itself, doing it on a spindly flexy lathe with any repeatable results will be difficult at best.
As I mentioned above the picture was a test on a piece of the material used to make the part, same piece of stock, same lathe, same tool, same setup, same program, same hour.
The test was a success, the actual part was a failure the first time.
Eagle Rock also recommends using 2 coolant nozzles, one for each knurl which I did.
As I mentioned above the picture was a test on a piece of the material used to make the part, same piece of stock, same lathe, same tool, same setup, same program, same hour.
The test was a success, the actual part was a failure the first time.
Eagle Rock also recommends using 2 coolant nozzles, one for each knurl which I did.
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