Sunday, October 26, 2008
On the last small run of Battery Boxes I did, there was a huge amount of interest. I sold 5 pairs in less than an hour. So I have done another, bigger run. I’ve got 12 pairs to sell.
Construction: The side walls, top and bottom are made of expanded cell PVC sheet (1/4”). The end pieces are made of PVC pipe, sliced in half. All joints are glued heavily with PVC cement. They are sturdy enough to stand on.
I have not put any holes in the front for the cables or the sides for mounting to the feet. If you are putting motors inside of them, cutting a hole in them and mounting them shouldn’t be a problem. But I don't know if different motors will be compatible with the 1/4" sidewalls and the reduced width of 2.9". These have not been tested for NPC motors.
Specs: These boxes are to club specifications with one exception. The width of the boxes is about .1" shy of the 3.00" blueprints. PVC pipe with an exact 3" outside diameter is difficult, if not impossible to find.
The inside dimensions are 1/2" smaller than the outside.
Finishing: The boxes have been finish sanded down to 320 grit. All the joints are smooth and clean. They are almost ready for primer. They may need a bit of touch up sanding here or there.
Price: $85 a pair plus shipping. Email me at firstname.lastname@example.org for exact shipping costs, and paypal that email address to place your order. I should be able to get them shipped out with a day or two of getting the order.
Monday, October 13, 2008
Here are the little tube things that go on each side of the center ankle and on the outer ankles. It took a couple of tries to get them just right, and I am still not perfectly happy with them. But I think once they are painted they'll be fine. I cut 1 inch (inside diameter) pvc pipe to length. Then I cut little squares of 1/8" pvc sheet to glue to the ends. I glued those and let them sit for a few days. PVC cement gets a lot harder if you let it cure for a while. If you sand it too soon, it'll be more flexible and soft than the surrounding material and you'll sand it out of the joint and make a groove.
Once those were cured. I used the sander to round the square pieces down to match the round edge of the pipe. This wasn't a very reliable method for getting them to perfect circles. But I couldn't think of another method that would leave me with no seams.
The little channels that are cut into the circumference of these pipes are supposed to be .03 " wide or so. My table saw blade is .1 so that was too much. My bandsaw blade was just right. I figured out the depth of the channels and put a stop on the crosscutting slider on the bandsaw so that it would stop the piece just after the blade began to cut the pipe. Then I would carefully roll the pipe into the saw blade, keeping the slider still. So it cut a groove all the way around the pipe. This was a reliable and good method with good results. It just took 15 minutes to cut all four pieces and a spare. Then I cut the little hexagonal end caps for the tubes and glued them on. A little more sanding and these will be ready to go.
Here are a couple of pictures of the finished shoulders. I'm pretty happy with these. In an earlier post I detailed how I built up the plywood pattern for these that would guide the router roller bearing as I cut them. I cut all 16 or so pieces, and glued them all together in stacks to make these ribbed assemblies. Then I sanded the outside edges down to clean them up. I spend some time putting putty on the insides of the interior pockets, as you can see, and then routing those on the forms again to clean them up. This wasn't the perfect method. If i was doing these again, I wouldn't cut the interior pockets out at all when I was cutting the individual layers. I would wait until the whole assemblies were glued up and then I would drill a hole in the middle of the pockets, and then rout that out once and all at once. Make sense? That is, instead of routing these pockets out 16 times on each individual layer piece, I would glue them all together and rout them once. Then I'd get really clean aligned inside edges. And there wouldn't be the need for putty. But I think these will clean up for paint just fine. The three dowel holes will get filled later. And I think I'll put some dowels sticking down into the legs for attachments.
Saturday, October 11, 2008
I've got R2D2 Battery Boxes for sale. I have 4 extra pairs. They are constructed from PVC. They are rough sanded and just about ready for primer. They may need a small bit of filler, and some spot sanding. They are to club specs with one minor exception:
Full Disclosure: The boxes are 2.87 inches wide instead of the called for 3.00 inches. PVC pipe with an outside diameter of 3 inches is very difficult to get in the US. But the difference would only by noticeable to someone with calipers and a copy of the blueprints.
They are $75 a pair, plus shipping. I can have the boxed and shipped very quickly. Paypal my email: email@example.com. Send me an email with any questions.
Here's a couple more pictures: