Total departure from plywood, MDF, and HDF for today's entry!I went to a co-worker's house yesterday who had volunteered to break out his metal lathing machine (which he hadn't used in a year, I found out), and brought along the aluminum I had previously purchased. But, on the way, I first had to CAF-FEI-NATE!, so I stopped at a familiar Seattle site. As usual, when someone asks how my day is going, I will give them a literal answer rather than a "Oh, I'm gooooood, thaaaaanks." So, I told them I'm on my way to build a part for my Dalek. Then, when my coffee order was ready, I saw this.
So that started the day off in a lovely way! Anyway, on to the more interesting stuff. I'm not going to describe all of this in too much detail, for my friend did most of the work, and I was essentially in a quality assurance role.
First, we needed to mount the aluminum and center it, since the piece wasn't too much bigger than what the width of the finished piece would be. Oh, by the way, we worked on this thing converting from metric to imperial all the while, to the 1,000th decimal point! For this piece, we needed the OD to be 54mm, or rather, 1.692 inches. He had an interesting gadget that measured the surface of the mounted piece, and he would hand-spin it to see the variations as it turned, making minuscule tweaks to the mounting posts as he did so.(Side note: I had swung by Lowe's on the previous day and found a scrap of corrugated pipe that looked like 1" in OD, but turned out to be wider. It's a pity, since I liked the thick walls of this pipe. However, it was too wide ultimately, and that sucker was *heavy*. Good weapon to thwart burglars, though.)
Then, we had some fun geometry errors when lining up his angled cutter mount, accidentally using the reciprocal angle of the one we should have been using (which, if you're keeping score, is 38.66°). But, the good thing about a mistake like that is you can correct it. We changed to the correct angle, and shaved off the incorrect one!
Wash, rinse, repeat, until all angles and interior diameters were cut, then we sanded and cut off the piece from the remainder of the stock.He then proceeded to lathe down a piece of wood, mark eight lines on another, and bolted the two together with the gun boss tip mounted on. This then got clamped onto his drill press table, and the decorative holes were then marked and drilled. This was when we both noticed that the center band where the holes are drilled wasn't as wide as the plans (5mm), so our decorative holes were a little big for it. I don't really mind, though. What bothered me a tiny bit more was that the spacing between all eight wasn't exactly uniform due to drill bit drift, along with the unclamping and reclamping of the jig. But, you'd have to be really close to the Dalek to see that.
Next up was drilling the holes for the rods. I had brought the rods with me to his house so that we could test the holes as we cut them. And we got them nice and snug! They are 3/16", by the way, or ~0.187". I didn't want to use the decorative holes as a guide since, as I said, they were slightly non-equidistant from each other. So we checked and rechecked and rechecked before committing to the plunge of the press. We also wound up drilling all the way through the piece (instead of stopping just short of the barrel) so that the rods have the maximum amount of space to be set within.Roughly 5 hours later, we were done. It surprised both of us that it took that long! The final piece isn't perfectly symmetrical, but I think it's going to be fine. We learned a few lessons and will be applying those for when we next get together for the base of the gun.
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