Saturday, September 8, 2012

Being stubborn, or learning a new skill?

After the sucess of pulling the panel I decided to make new baggage decks. The PA baggage decks are a beautiful wood that needs to be sealed and carpeted, weight about 3.1# each. I took it as a challenge to make lighter ones out of glass and foam.



I found that a nail punch worked great for making holes in the foam.



Instead of the lousy Harbor Freight vacuum pump I tried a venturi adapter by West Systems off my air compressor. Bad idea #1, it meant running my 20 gallon air compressor for over 6 hours.



Bad idea #2. I had read that you could run 2 lines to a large mold to increase the vacuum. I took this to mean you could run 2 molds at once. Nope, the most I got was 15" of vacuum.



Bad idea #3 can be seen under the molds above. I tried an old trick of taping plastic wrap to a work  table as a release agent. Instead the tape was not tight enough, the plastic lifted off the table,  and they both were junk.



That's why they call it learning, it was off the Fiberglass Supply for a new load. I like my Imprenza, but I miss the cargo capacity of my old '85 Mazda GLC. I could fit an entire sheet of 4x8 plywood inside with room to spare.




First was to make a better place to use as a mold. I tried applying a coat of 3M spray glue to a piece of MDF, and laying 4mil sheet over it...



but when the glue set up it outgassed, leaving bubbles and making it useless. 



Instead, like I used for the panel layup, I bought a sheet of  finished MDF and trimmed it down. Ironically, the perfect material is a sheet of glass, plexiglass is also an option but both are cost prohibitive. The green film is a water soluble release agent.




I also went with a good vacuum pump. Amazing how much quieter it is, and how little oil it throws compared to the cheap HF unit. I was even able to add a piece of tubing to route the breather oil outside the hangar.



 

Voila. Much better. Still got the gaps in the bottom layer, I think my slurry mixture is too thick and doesn't compress/spread well.The gas are not air bubbles, they're solid down to the foam. If it had been a structural member I'd probably redo it, though.



Old and new. The little hump in the middle is sanded off and a piece of scrap glass laid in.




Just for practice, while I had everything out a did another layup with scraps. Later on I'll use the tools and equipment again to reinforce the nosedeck.




Was it worth it? I saved ~0.5#/deck, but the glass will be easier to work with for something I want to do to them. Plus I learned a new skill, who knows when that will come in handy. And it was fun, too. Can you put a cost on any of that?

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