Tips for knurling

[@Roadrash-fk9rn]

Finally a person with a spanner wrench 😊. I love seeing people use the proper tooling.

[@occasionalmachinist]

I certainly could not apply the torque needed without it, and something like vice grips are too dodgy for my liking

[@37yearsofanythingisenough39]

First person on KZbin to speak the truth. In 55+ years of machining I have never calculated the diameter of the stock for knurling and they have all turned out for me as well!

[@occasionalmachinist]

I can understand that in theory you could, but why do it if you don't need to?

[@JB-ol4vz]

Very informative as always. Thank you for taking your time to make these films.

[@DK-vx1zc]

Great explanation. thanks for sharing

[@occasionalmachinist]

Hope it helps. Lots of people say they can't knurl, but like parting, it's a knowledge/ practice thing

[@Warped65er]

Thx for the vid.

[@azenginerd9498]

A while back Mr. Pete / Tubalcain discussed (ranted about) the lack of need for a specific diameter to successfully knurl. Being an "armchair machinist" I decided to do some calculating on the matter. Here are some knurling numbers to ponder... The "pitch" of knurling wheels seems to follow an industry standard: Coarse = 14TPI = 0.071" pitch Medium = 21 TPI = 0.048" pitch Fine = 33 TPI = 0.030" pitch IF the workpiece OD was important for a successful knurl, the circumference would need to be an even increment of the pitch in use. For example, the circumference of a nominal 1" diameter workpiece divided by the pitch and rounded up to the next whole number comes out to 44 coarse "teeth" and a specific diameter of 1.0004" (25.41 mm) The next larger diameter corresponding to 45 coarse "teeth" is 1.0231" (25.99mm) - a difference of 0.023" (0.58mm) (or the pitch / pi). Similar calculations for a medium wheel give a difference of 0.015" (0.38mm) and 0.010" (0.25mm) for a fine wheel. But you don't knurl at the surface diameter. The knurl "pitch diameter" should be smaller than the stock diameter by about 50% of the pitch. If the stock OD was critical, you would need to dial in your knurl pitch diameter in the range of 0.005" to 0.010" (0.12mm to 0.28mm). Those are pretty tight numbers to try to adjust a bump or scissor knurling tool to on the fly.

[@occasionalmachinist]

Exactly.

[@paulmorrey4298]

Thanks

[@replicant357]

7:08 I’m not even close to being called a machinist, but even I have “partake” in such naughty practices 🤣

[@occasionalmachinist]

I thought I'd mention it. If it helps 🤷‍♂

[@MarkATrombley]

EP Grease = extreme pressure grease. Had to look that one up.

[@occasionalmachinist]

Always a balancing act about what you spell out vs what you leave as an abreviation. Always learning...

[@MidEngineering]

That's a nice tool. Better than the one I have that has pivoting arms, which sticks out too far from the tool post & is a bit flexible...

[@occasionalmachinist]

They are probably available on the usual online second hand sites

[@HM-Projects]

Heh not cheap. $250+ even for used ones. I made myself a similar version, works well. Got the Aloris wheels on sale from Amazon to go with it. It's a good design, bit overpriced though.

[@occasionalmachinist]

@@HM-Projects I bought mine many years ago, so can't comment. They do work well though.

[@karlulvestad7155]

Material displacement👍, yep either push till you get it or calculate for diameter😁

[@occasionalmachinist]

I must admit - one day I'd like to get a strobe light going while knurlling. I think video of that would be rather cool

[@philcook9967]

Please let me know where I can purchase a 6 jaw chuck like the one you are using to hold the bar stock. Thanks - Phil

[@occasionalmachinist]

That's a Pratt & Burnerd EC Collet chuck (@thisoldtony has one too - a source of some amusement to my friends). I don't think they are are made anymore. Your best hope is to watch eBay, or possibly some of the industrial clearance auctions/ sales

[@billdoodson4232]

Knurling is not something I do very often at all. When I do, I just put the diamond tools on the bar (no matter the dia) and its always come out fine. I have never calculated anything, maybe I have just been lucky. I always use Rocol RTD as a lubricant.

[@occasionalmachinist]

No. Just sensible.