This project was created on 05/15/2014
So here's the deal. I was starting to run out of time and didn't take enough pictures of the final steps. But here's the gist of it all:
I have a backpack with a laptop area. I made a square out of 3/4" PVC pieces which fit snugly in this pocket. On the top of the square is a "T" pointed upward that receives the pipe connected to the skull.
I did trench out a channel in between the two foam halves to hide wires for putting LEDs in the eyes. But like I said, no time. I boxed this up and shipped it to San Francisco. One joint on each of the wrenches has not been cemented. I thought about using cotter-pins but I think the friction fit will be good enough for one weekend and it makes this quite easy to pull apart and toss in a bag if I need to.
So if you're at Maker Faire this weekend. Look for the floating Skull and Wrenches that looks like it's chomping on my head.
After the glue had set I cut off any that squeezed out. It was then time to lay out the pieces so that I could drill holes for PVC fittings.
I used some straight edges to make sure the pieces were aligned. I then drew layout lines with a sharpie on both pieces. These were to help ensure the hole I drilled with a hole saw was as straight as possible. Here's a test piece I used to make sure my plan of gluing PVC junctions in the foam would work:
The image below shows it with all the pieces in place, but I didn't glue in the fittings yet. This is because I wanted to remove the fittings for part of the paint job.
Time to paint! I first coated everything with matte black:
I ended up putting two coats on each side, paying special attention to the edges. Here's the thing, spray paint has acetone in it. Acetone dissolves polystyrene. But if you keep the can far enough away and don't let the paint pool it won't eat the foam.
My plan was to have black edges and silver with metal flakes on the faces of the logo. So I kept the waste from the cutting process. After removing the PVC fittings I put the foam pieces back together and used it as a stencil:
I used some spray adhesive I already had on hand to hold the foam sheets together while I cut them out. This adhesive didn't form a strong bond, I planned to use Gorilla Glue (polyeurethane) but I thought this glue layer might be hard to cut through.
I first traced the paper patterns with a sharpie. Then slowly cut out each 2" thick shape. The video above has been sped up ten times.
With all the pieces cut out I separated them and cleaned the adhesive off with some rubbing alcohol. I then spread a thin layer (as thin as I possibly could) of Gorilla Glue between the halves and clamped them together to set.
Wrenches (this has been curing for 2-3 hours)
The skull during curing.