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Revision as of 23:24, 22 December 2015 by Jeff (talk | contribs) (→‎Vacuum Bagging)
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Material Selection

Google's cache of the now-defunct www.pe.net/~rpm/about2.htm mentions:

  • All gas tanks are made of vinyl ester resin for chemical resistance to gasoline.
  • Fenders and side plates are made of iso-flex or DCPD resins, no low grade ortho resins are used.
  • All parts are made with iso-flex gel coats to reduce cracking.

Epoxy Resin vs. Vinylesters and Polyesters at Red Rock Store. This is an excellent layman's explanation of the different chemical properties of resins.

  • Epoxy resin
    • Strongest molecular bond
    • Will crack along a single line rather than splintering
    • Minimal shrinkage
    • Thin resin, easier to thoroughly wet-out fabric
    • Excellent repairability
  • Vinylester resin
    • Essentially polyester resin toughened with epoxy molecules
    • Weaker molecular bond than epoxy
    • Difficult to repair/patch
  • Polyester resin
    • Cheapest resin available
    • Highest water absorption
    • Highest shrinkage
    • Spider cracks when stressed
    • Difficult to repair/patch

Vacuum Bagging

  • Vacuum Bagging On $50
    • Glad ForceFlex trash bags are polyethylene and are suitable for vacuum bagging with epoxy.
  • JoeWoodWorker.com has some excellent guides intended for applying veneers to woods.
    • Project EVS is a how-to guide for building a very advanced vacuum system for a relatively low cost.
      • Uses two vacuum reservoirs made of Schedule 40 or 80, solid-core PVC pipe. Just as an air tank prevents an air compressor from having to run continuously, a vacuum reservoir reduces the strain on a vacuum pump.
      • Uses a vacuum controller to switch the vacuum pump on only when additional vacuum is needed.
      • Uses a "3-way Mac Valve" to relieve vacuum from the vacuum pump, which otherwise might prevent it from re-starting after cycling off.

Resources