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jroma1

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For the past several years I have tried to knurl using the old familar rocker type and the one that came with my QCTP tool post. In either case I continually have had poor results. There are those that believe the scissor version is the best and I have to agree. The photo above shows a homemade scissor type knurling tool that I made and it has for the first time shown in some decent fashion,reasonable results.

The basic frame is made using 1018 CRS,the lead screw I believe is 12L14. Both the top and bottom bars are attached to the "T" bkt with grooved pins (for lack of a better description)that are secured with what I'm told are called "E" clips. There is some side play which brings up a question;how critical is that characteristic should this be a tight fit?


ANY COMMENTS SO FAR?


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The homemade screws shown above are also made using 1018 and if you look close enough you could detect ware.
Question;Would it be wise to temper these screws

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This photo shows what the knurler can do,I purchased two sets of knurlers,medium and coarse. The medium knurl doesn't look too bad,on the other hand the coarse leaves something to be desired some of the diamond pattern looks pitted. I purchased the two pair of knurlers from the same supplier OD = .750 , ID = .250 , HT = .375 The ID of the coarse knurlers is .015"larger then the medium set,could this be a problem

ANY COMMENTS

I'm still learning any comments suggestions will be greatly appreciated

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They don't look too bad but I do see what you're talking about. You should be able to get fine results with the scissor type tool. In your shoes, I would roll-out the knurl and manually calculate the pitch. Out of curiosity, how much did the knurls cost? Reason I ask is that good ones are upward of 30 bucks (per wheel!) -and it makes a difference. Also, use the search feature here and look for other knurling threads. There are a couple good threads here and some time ago, I posted a spreadsheet that caluclates proper diameter. You can also fine-tune the pitch value to match your wheels if they prove to be off a bit (and most of the inexpensive ones are off). I had some cheaper wheels and the holes were not well centered and the pitch varied. It's those finer details you need to look for...

Also, technique is everything. Takes a lot of cutting oil and practice. I find chomping in hard and fast gets best results.

Ray



jroma1 said:
View attachment 46255

For the past several years I have tried to knurl using the old familar rocker type and the one that came with my QCTP tool post. In either case I continually have had poor results. There are those that believe the scissor version is the best and I have to agree. The photo above shows a homemade scissor type knurling tool that I made and it has for the first time shown in some decent fashion,reasonable results.

The basic frame is made using 1018 CRS,the lead screw I believe is 12L14. Both the top and bottom bars are attached to the "T" bkt with grooved pins (for lack of a better description)that are secured with what I'm told are called "E" clips. There is some side play which brings up a question;how critical is that characteristic should this be a tight fit?


ANY COMMENTS SO FAR?


View attachment 46257

The homemade screws shown above are also made using 1018 and if you look close enough you could detect ware.
Question;Would it be wise to temper these screws

View attachment 46258

This photo shows what the knurler can do,I purchased two sets of knurlers,medium and coarse. The medium knurl doesn't look too bad,on the other hand the coarse leaves something to be desired some of the diamond pattern looks pitted. I purchased the two pair of knurlers from the same supplier OD = .750 , ID = .250 , HT = .375 The ID of the coarse knurlers is .015"larger then the medium set,could this be a problem

ANY COMMENTS

I'm still learning any comments suggestions will be greatly appreciated
Click to expand...
 
Ray:
Thanks for your feedback,you are right,the knurler wheels are cheap. I bought the wheels from Victor Machinery at $10.00/pr. I should of known not ot expect too much for that price.

I don't know very much about pitch and as you might of guessed I don't know much about knurling. This spreadsheet you talked about how can I get a copy and is there any written info on how to use it.

Where did you purchase the better wheels.

Thanks Again

John Romano
Philadelphis Pa
 
My favorite are convex wheels from Accu-Trak. You can see some of my knurling on Ti 6-4 in post 9 here. They're $28 per wheel directly from Accu-Trak but the quality & results are fantastic, I won't use anything else now.

LMS has a simple calculator on their website that works well. I had my bro make me an app that uses their formula as one of the options for use on the PC and on my Android phone.
 
You can also use those convex knurls to make yourself a brass microscope type knurl like I have posted here with pictures of my work. For brass,I advise you to use a fine thread knurl as brass starts to fall apart if too coarse a knurl is used.

I make my knurls by running drill rod knurl wheels against threading taps horizontally or at angles while the tap is rotating in the lathe chuck or collet. I have described the process with pictures before.
 
the bolt that you are using to hold the knurls should be the hardest material you can get 1018 is not going to work. Many set ups use micrograin tungsten carbide for the pins. At the very least think about using a hardening steel like O-1 (hardened to a dark yellow) and even then it will need replacing on a fairly regular basis.
 
And indeed, it was the accu-track wheels I was referring to. Pretty sure Will (darkzero) turned me on to them and I got a set. Nice, real nice. They have contoured edges that allow for easy lateral motion. Only used them once but got good results. -Need to practice a bit more with them because it's just like anything else... For each piece of equipment you have, it's important to really experiment and get to know it. Even something as simple as knurling wheels needs practice...


Ray

darkzero said:
My favorite are convex wheels from Accu-Trak. You can see some of my knurling on Ti 6-4 in post 9 here. They're $28 per wheel directly from Accu-Trak but the quality & results are fantastic, I won't use anything else now.

LMS has a simple calculator on their website that works well. I had my bro make me an app that uses their formula as one of the options for use on the PC and on my Android phone.
Click to expand...
 
Ray C said:
-Need to practice a bit more with them because it's just like anything else... For each piece of equipment you have, it's important to really experiment and get to know it. Even something as simple as knurling wheels needs practice...


Ray
Click to expand...

Totally agree Ray! Knurling may be simple to most & in theory but for many others it can be very frustrating if you are trying to achieve that perfect knurl. Luckily I did not struggle that much (although I have at times) but I think that's because of the person who taught me & the tools I'm using.

Depending on the work diameter & the pitch of the knurl, sometimes the forces are so great when knurling Ti that I have to pin the QCTP to prevent it from moving. Carbide pins are a must for me, also got them from Accu-Trak.


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