@TBJK was awful modest with his show and tell picture of his turners cube. He sure didn’t take the easy route and start with a cube from square stock. He started with round stock, made it square and then did all the work. The attached video is not Tim, but it will give you a good idea of the scope of skill it took to get it done. Good Job! (and yes - anodize it for that wow factor)
I remember when it was just a baby…
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You beat me to the full post.
The whole thing was done on the Colchester lathe, This is United States so the measurements were all done in imperial. I used the large 4 jaw chuck for the entire operation. After it was squared up to 1.372, I had to come up with a way to hold the cube. First, I tried to create a jig to use in the 3 jaw but that didn’t work as I had hoped. Downfall was I spent a quite a bit of time trying to get that to work. This was with a piece of stock a few inches in diameter, with an inset area for the cube. The dimensions I made it to were tight, so tight that it did scar my cube one spot. The next way that worked for me was I used aluminum 1/8th thick strap, 1" wide. I smoothed the strap on the surface plate, then used these as shims to spread the load & keep from marring the finish. This was set up in the 4 jaw chuck & center accordingly. My worst setup was a total of about .0005 total out of center, so actual out of center was .00025
I bored the center bore with a 2 flute end mill, Then used the smaller boring bar from the sherlines to do each step. I did grind my own undercut tool. I took my time with this, that tool probably an hour alone. Grinding, cooling with water to keep from loosing the hardness needed. Each face was undercut when I still had each setup to minimize the number of operations & setups. While its not exactly perfect, its pretty close. The hardest part for me was trying not to get into a hurry, which I ended up doing anyway.
I had 4 sides done with the cube before yesterday. I did the 5th side before the committee meeting, Ironically, I was not going to stay to finish it, but was essentially challenged by my better half to finish it. After the committee meeting, it was back to the lathe after hot glueing the 5 other sides. This is done to keep the cubes from flopping around inside the other. My wife however thought it was some sort of sick gift wrapping.
Well enough with the Jib Jab & on to the pics, hopefully in order of competition.
First portion of the Recap.
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These next pictures are from when I trued up the cube. This is when I was using brass shim stock that I had. I cut that on the shear in the metal shop. You can see some of the writing in dimensions of how much I needed to take off on each side. The first one is a pic of centering using the magnetic base & indicator.
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This one is where I faced off for what was going to be my jig for quick changing. I couldn’t find any other pictures of it or the jig. The second pic is where I started by adding the 1/8th strap.
Here is the boring bar setup with the counter bore stepped faces.
Here is the custom tool I ground out of 3/8 high speed steel blank. The cutting edges were honed with a stone after grinding.
Here is the first series of undercuts, they are hard to see but they are there.
And the subsequent faces, I wont show too many of those since they are pretty repetitive.
This is for the last face. You can see the hot glue. Also note that this was essentially a rough pass taking out all but .005" off, this was left for the final pass with the undercut tool. I wrapped up with the final pass about 10:30 last night.
And a pic early this morning of feed of the glue.
The total of 4 cubes, 3 of which are inside another cube.
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Making tools to make the thing you actually want to make. Meta-making.