Michael K JohnsonJun 5, 2022
Michael K Johnson

I've been working on a design for a keyway cutting tool for my lathe, based on a morse taper 3 quick-change tool holder. I finally learned that I can make hidden line animations in FreeCAD that make the inside workings clearer, so here's one to enjoy. ☺

https://forum.makerforums.info/t/keyway-cutter-design-and-project/85441?u=mcdanlj

Keyway Cutter design and project

This project is a bust. I think it’s a combination of small amounts of bad implementation and large amounts of bad design. I did cut that 5mm keyway, but there were complications. It turns out that the reamer I used for the sleeve wasn’t really a tight enough tolerance for the tool rod, and it wiggles. Not very much, but when you are trying to take off about .001" at a time, it really doesn’t take much. There’s a bit of play in my compound. Not much, but trying to use this, every little bit ma...

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Jun 5, 2022 at 2:05pmWeb
Show threadMichael K JohnsonJan 22, 2023

All the recent youtube #machining videos in the past month or so caused a run on the Hemingway sensitive knurling tool, and also got me to browse the Hemingway site for other things that might be fun to make at some point. I found this tool:

https://www.hemingwaykits.com/HK1230

I'm happy with mine, though! ☺

Show threadsmells of bikesJun 5, 2022
@mcdanlj this is definitely clearer than just looking at the drawings on github. Thank you!
Show threadMichael K JohnsonJun 5, 2022
@smellsofbikes I'm already learning that I probably want the shaft tang and tension rods 40 or 50 mm longer, because the handle interferes with the handle on my QCTP while I'm trying to insert it. But that won't fundamentally alter the design.
Show threadMichael K JohnsonJun 6, 2022
@smellsofbikes The tension rod binds in the collar because the raw stock is slightly oversized from nominal so I need to file/grind it down to get sufficient clamping range, and I need to actually make some bits to cut with. But I can see the light at the end of the tunnel.
Show threadMichael K JohnsonJun 6, 2022

Sleeping on it, I decided to design the collar deeper and thicker and add a separate screw for clamping the collar from the screw for the pivot. It seemed parsimonious to have one screw do two jobs but I've decided that was false economy.

I'll try adding the clamping screw to the existing collar, but won't hesitate to use the same ¾" material I used for the handle to make a new collar too.