Making a Knurling Tool for the Lathe (Narrated)

In this video i'm making a knurling tool for the lathe.

I needed to make a straight knurling for my „combination lock“ video on my main channel. I did use my friends knurling tool in a previous video, as it's good to have your own I decide to make one. I bought two straight knurling wheels and now I only need to make a holder for them to use it on the lathe.
The first thing I did was making a drawing of it with all the measurements and tolerances. Once I knew the dimensions of the finished part I could organize the material. As material I choose a heat treatable steel 36CrNiMo6 (1.6582). The good thing about this steel is you can't overheat it when hardening and ruin the hardening, as I'm just going to harden it with a blowtorch that's perfect. The piece was much bigger in the beginning than it actually needed to be, but that's no problem I'll just take a few cuts more and make some more chips. I got this part for free from my friend, so I was happy to get started. First, I turn the part to lenght on the lathe (120mm). Next I did mill it to it's dimension 20x25mm, once I had this done I took out the step 5x95mm. Then I milled the slot for the knurling wheel. Once I got that I only needed to make the hole for the pin and cut the thread which will hold the pin. After the machining I did the heat treatment. Heat it up to around 800°C (cherry), hold the temperature for a moment and quench the part in oil. After that I needed to temper it to take a bit of it's hardness and stress away. Because of the high temperatur of the quench the part turns black, but it won't stick properly and start to peel of. So I cleaned it all up with Scotch Brite and then I used the bluing liquid to give it a nice and even black finish. The final test worked very well. By the way, I didn't clamp the knurling tool 90° to the part, I clamped it at 91°. This way only the right edge of the wheel will cut to the final diameter, which gives it a much nicer finish.

I hope you like my work and the video.

Huge thank you to all of my Patreon and PayPal supporters and specially to:

Afreeflyingsoul
Stewen Guyot
Adel AlSaffar
Alan Hanson
Amanda Taylor, Esq
Andreswara Hermawan
Andrew Phillips
Dan Williams
Gregory
Joan Casanovas
John Romero
Jonas Richartz
LVE
Marc P
Paul Ambry
Paul Mampilly
TallBaldandCrafty
Trevor Kam
Vince Valenti
Zachary Grimes


Timestamps:

00:00 intro
00:08 showing the knurling wheels
00:18 showing the drawing with the measurements
00:26 showing the starting material (36crNiMo6)
00:46 turning the part to lenght on the lathe
01:30 making the part 20x25 on the mill
03:01 making the step 5x95mm on the mill
03:51 turning the mill head 45° and mill the big angles
04:26 milling the slot for the knurling wheel
05:13 drilling and reaming the hole for the pin
05:58 drilling and threading for the threaded pin
06:30 removing all sharp edges
07:16 preparing the hardened pin
07:52 test assembly before hardening
08:16 hardening and tempering
08:51 bluing with bluing liquid
09:19 assembling
09:33 final test
10:56 footage of the „combination lock“ video
11:20 showing the finished knurling tool


Time and costs of this project:

I was working on this project for 1 day
$80 two knurling wheels


I turn a Stainless Bolt into a Combination Lock:
   • I turn a Stainless Bolt into a Combin...  


My main channel:
   / @mymechanics  


My camera:
Panasonic HC-V180


If you have any questions about the process, machines i'm using or other stuff, just ask me in the comments. I read them all and i try to reply as soon as possible.

Sorry for my bad english, it's not my language. I try my best to improve my technical english.

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Thank you for watching :-)

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  / mymechanics