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Production Jig for our Rocket Launch Controllers

We manufacture Rocket Launch Controllers for amateur rocketry. A year ago when we were starting up, our son bought us a small Shapeco CNC. One of the features of our wired controllers is an ethernet port to connect the controller to the remote console. I had been struggling to figure out how to cut the shapes consistently with what I had in a reasonably appointed shop. Needless to say, I was off to the races a week after opening that package, and then discovering Easel.

The issues with that small hobby machine were two: My polyethylene stock is really tough and I had to reinforce the Z axis motor mount and bearings, as the bearings would constantly work their way out or the plastic motor housing; I had to cut the larger part, the controller spool, in three jobs - shifting and flipping the piece as needed. There was also the issue of vacuuming up between each job.

I did learn how to fashion some pretty slick clamp jigs out of scrap polyethylene. They allowed me to secure the material with screws on the side or the piece.

So our first project on the XCP was to machine a special wasteboard overlay designed to cut these parts in bulk. Our stock is 24x48x0.5" Weather-Resistant VHMW Polyethylene. Each sheet is cut on a table saw and yields 7 spool cores and 9 side piece sets for consoles. After cutting all of the parts, I would take the spool cores to the table router and route out 0.25" channels where the spools bend so that I could form the core of the spool.

The jig also has inlay-ed pockets where the job cuts all the way through the stock. The idea of wasting wasteboard does not appeal to me at all.

So with all of the room provided by the 24x48" XPC I set out to make a jig to clamp down 6 cores and nine console pieces so that I can cut the common features in one fell swoop. I will still have to break this into three jobs, as some features are cut on one side, others on the opposite side - all with 1/8" end-mill bit, and the routed bends work a lot better with a 1/4" mill-bit.

I also cut some clamps from walnut. I was very pleased with how those turned out. The hardest part of the job for me was transposing the holes for the clamps #5 hex-head screws to the back of the board to cut inserts for the t-nuts to screw into. I am going to need to add a 36 or 48" rule with mm scale to my tool kit. The one we have now is fine for rough carpentry.

Our next challenge is to accurately lay out the ports across what Easel considers a solid 24x48" piece of stock.

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