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The Last of the Fiberglass

Posted by qwindelzorf on April 21, 2011

We are finally done with the fiberglass layup!  Horray!

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We did the last two knees and the other body shells yesterday, and today we finished them and cleaned them up.  This time, when doing the knee molds, we used an alternate process for actually applying the resin and cloth.  First, using a brush you are willing to throw away in 10 minutes, the interior of the mold is painted with resin. Then, dry fiberglass cloth is laid into the mold and massaged into place by hand (with gloves).  Then, once the fiberglass is in approximatley the right place, more resin is painted on the inside. The brush also works well to poke and prod the fiberglass sheet into all the corners and such that are otherwise hard to get to.

This process worked spectacularly.  These are probably the two best pieces we have produced in this whole project to date. No wrinkles, few bubbles.

The other key trick turned out to be relatively simple.  Pull the shell out of the mold before it has time to fully cure.  As the resin cures, it goes through a series of phase changes.  First, it goes from a viscous liquid to a chunky gel, kind of like Jell-O.  Then, that begins to set up and it becomes a crumbly rubber, which is easily broken.  Next, it begins to harden, and feels like a stiff rubber.  This is the time to pull the part.  It can then be put back into the mold to cure.  Over the next hour or so, it will go from rubbery to hard, at which point it can be re-de-molded and finish work done.

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The last thing we did this evening was to give everything a coat of primer, mostly to bring out the flaws and give us an idea of how much work we have left.  Its not readily apparent from this picture, but the answer is "lots". We still have to:

  • build the support frames for the pods
  • build the gun-boxes for the pods
  • build the support frame(s) for the body
  • Assemble all the frames
  • Bondo the shells
  • Paint and finish the shells
  • Build the mechanical parts that will make it move
  • Build the electronics
  • Program the electronics
  • Put it all together

Even with all that though, I estimate that we are now past the half-way mark.  More importantly, we are done with the single most laborious and tedious task in the whole project. From here on out, it should not be nearly so mind-numbingly dull.

So, next stop is cutting out all the frames.  That'll probably be next week sometime, as we are both busy for the next few days.