slot blog thread
.. I'm going to s-l-o-w-l-y have at my "version" of the Puzzle Pan chassis that Steve is building. It definitely won't be correct for the time as I'll make some changes along the way wherever it seems like a good idea.
For one, I'm doing mine out of hardened tool steel from a saw blade. After sanding off the lacquer and getting it down to a #320 grit finish, the steel blank I used came in at around .033" or so. The main pan had nice flex and weight once cut it seems (?) and it's really strong of course. There was no way I would attempt to heat and offset the drop arm, so I made it in two pieces (a man's gotta know his limitations!).
Also, once I brought a .jpg of Steve's drawing into my CAD program and traced it in 1:1 scale, I decided to scale it up slightly to a width of 3-1/8". My method for drawing the thing out on the steel is a little different from Steve's and as you can see from the picture, less accurate than his military spec precision. shok.gif My cuts are nowhere near as beautiful as his either, but it should work fine.
I simply cut out the pieces from a sheet printed at 1:1, lay them on the steel and scribe them with a carbide point. Just as far as I got today took me over three hours, so I'm going to put this aside for a while before I get motivated enough to have at it again. My eventual plan is to put a vintage Mura can in this thing that I fixed up a little and mount it can drive (another non-accurate aspect... ahhh what the heck). Anyway, until I get the desire to go back at it again, I got this far:
In keeping with my less-than-speedy build here, I got one more piece of this puzzle that I may use (or not).
Looking at the details of construction and function as explained on Steve's site, I thought that another way to achieve some vertical "slop" between the motor plate and the main pan was to just use thinner steel. I have some .020" steel from some other tool here and cut and fit it oversize for now (I'll trace and cut everything to fit the motor box after I struggle through that part later on!). However, with the main pan being .033", there's a difference of .013" between the two and that's a LOT more than the several thousandths Steve set up. It seemed like a good idea since, being lighter than the main pan material, it would shift a little of the weight forward and to the sides... and I could always grind the side stops to fit lower down instead of further up... I guess. In any case, I may just cut and fit another one out of the samw saw blade as the main pan.
For a bracket, the steel Slick 7 one seems appropriate and is going to save a lot of tedious and probably sloppy looking fabrication time. :-)
When I'm cutting something like the main pan on this thing, I would hate to screw something up because of all the time and material involved in that single piece. Having the drawings (and being able to re-scale things because of the CAD software), gives me a little peace of mind. Besides, I don't even own a machinist's square (or a jig for that matter... yeah I'm a caveman), so being able to cut the drawings up for patterns/templates allows me to lay the thing out more accurately.
Rick, thanks for the encouragement. Obviously, my build will not look anywhere near as nice as yours or Steve's (duh laugh2.gif )... but the whole concept of this thing had me intrigued as soon as I saw it. I guess it's both because of just how cool looking the thing is, but also how different it is from the various hinged designs that have been around for... decades; hats-off again to Sandy Gross!
I've been looking at both simplifying the design and trying to figure alternatives to hinging the drop arm and body mounts (but allowing for movement) for a totally hinge-less design as an extension of Mr. Gross' concept, we'll see how that works out . blink.gif
On the steel thing, I wish I had a Laser Dude but have no doubt if you decided to cut one of these out with a Dremel it would still be perfect. Anyway, a guy has to use the tools at hand. However, for all it's difficulty, steel does present opportunities because of it's strength-to-weight and there are already some pieces I see on the original I won't have to use because of those properties.
With all these puzzle pan builds around, maybe there should be a puzzle pan proxy in Peoria or Pittsburgh or Pawtucket? Heck... if Tony P had a puzzle pan for the puzzlepan proxy in Peoria, Pittsburgh, or Pawtucket (with pizza and prizes of course), THAT would be the penultimate puzzle pan proxy
On the side aspect relating to the motor, I've prepped a nice old arm by carefully cutting-off (the wire was really on there and couldn't be dewound) the wire at the bottom of the arm with a thin Dremel disc to avoid damaging the cardboard stack ends. I tossed the original com and installed a Kirkwood set at 20 degrees advance, did two coats of high-temp on the inside and polished it up ready to wind. Overall length is a bit longer for the Mura two-hole can and I'm thinking this will be a #25 awg wind, but not crazy-hot.
Can is a vintage "A" and the endbell is Tradeship. One thing I noticed was I just could not sand out all those pits in the steel can. I started with a belt sander and moved progressively through wet/dry sand paper finishing up with steel wool. The idea was to have the can match the finish of the chassis. Close enough, but too bad the steel in the can was not as good as the saw blade material John used for the chassis.
German-made ball bearings on both ends of the motor, soldered brush hoods, shunt wires, spring insulation, and spring post protectors round out the build. The magnets are old and have weird wedge shaped edges but were still quite strong! (Vintage Arcos maybe?) They wouldn't fit into the "can in a can" shim so I shim'd them up with .005" sheet steel.
Might need a zap for sure but thus far running it for a minute on the bench... no heat was detected. Of course under load things could be very different.
Spins up crazy-fast with so little internal friction (light brush springs) and I am afraid to give it more than 4 volts! That is a nice wind there, John!!!