Hello, everybody. I have been on a new med and have lost 30 of 80 pounds overweight. I have also learned that I am diabetic, mildly.
To safely transport and store the ultracapacitors I use in my electric bicycle, the seller wrapped a wire link around each pair of terminals and tightened them, stretching the wire but more importantly shorting the electrostatic charge of the capacitor.
I am building a parallel / series relay switch board for banks of eight caps and needed to know if my plots were on scale so I plotted out an early version and went over to Dixie to get two pieces of 4 x 9 x 1/16 inch aluminum to make shorting plates for banks of eight. I have two banks, or rather I have sixteen caps randomly assigned to two groups.
I used a 1/16 inch clear dot at 100 dpi with a black cross through it, surrounded by four eight-by-eight black squares with white between them, for a total mark size of 17 pixels. Rather than either of my two optical center punches, I used an automatic spring punch.
I brushed rubber cement on the metal and taped it to the window to form a light table. I positioned the plot carefully and worked it down slowly. Then I foolishly applied rubber cement to the other piece and stuck it on.
Foolish because I should have used a construction paper interlayer between piece, and a wooden underlayer to cath the extreme burrs developed.
When I started drilling with the 1/16 inch bit in the center punched holes, the first one was OK, but then the metal got gummy and I forgot to use WD-40 so it got worse. Also, the very first hole should have showed me I had a burr problem. I impatiently continued drilling with various combinations of burr lengths and locations interacting with the fixturing holes and slots in my drill press table to produce various out of level, that is non-normal positions. It got worse and the rubber cement let go by a sixteenth of an inch. I should have pinned or rivited the pieces together once I got that burr. I just couldn't stand the delay.
At the very least I could have put the work on styrofoam. I have a lot of it and use it for drilling all the time. The meds have somewhat clouded my mind. Soon I will be a Californian: lean, trim, presumably tanned, but stupid. I hope they give me the even more stupid making weight loss drug soon.
I corrected the error and got the holes lined up, then expanded them to 1/4 and then reamed 5/16 from both sides to get the burrs. I finish deburred with a larger drill bit held in the hand.
The rubber cement removed easily.
Perhaps next week I will run the whole thing again. The two pieces of aluminum were only five dollars. No cut charge.
On assembly, all sixteen caps went into their positions without interferences or any need to enlarge a hole. The studs are 6 mm, and the screw heads wide. So all in all, it came out OK.
I wonder what alloy that was. Probably 6061, they only mention one in the sales dispaly. That is they show "aluminum" samples, and don't mention any alloy at all.
The PC board design is nearly done and will likely be cut in vinyl by the local sign shop. I may save a few dollars by weeding the cut myself. It's one big weed, plus all the hole locations. Etching will be easy. Disposal of copper solution is a problem. I'm inlcuding "filler" in the PCB to reduce the amount of copper removed and so put into solution, and so requiring careful disposal.
My senior project at ODU: Google Groups, then "dgoncz" and some of: ultracapacitor bicycle fluorescent flywheel inverter Equipped with BoBike Mini removable child seat, too!