Polyester gelcoats and porosity

Discussion in 'Materials' started by bigjonny9, Nov 13, 2014.

  1. bigjonny9
    Joined: Apr 2010
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    Location: New Zealand

    bigjonny9 Junior Member

    I am interested in producing bathroom vanities. I have done a little research to find that there are not to many companies actually producing fiberglass vanities. I am a qualified boat builder and have dealt with polys/vinyls and epoxys for years. However I feel like I am missing something fundamental. I notice that there are plenty of companies offering fiberglass baths and shower surrounds but not vanities..My thought is that the gelcoats could be to porous and that they could stain easy? therefore having issues with warranties? I do understand that there are acrylics and plastics out there but I know I could build plugs and fiberglass moulds and products relatively cheaply so what am I missing?
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    I think that gelcoat is softer and stains easier than the acrylic.
  3. ondarvr
    Joined: Dec 2005
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    Location: Monroe WA

    ondarvr Senior Member

    There are many thousands being made with gel coat every day. The cultured marble industry makes counter tops, sinks, bathtubs, showers, etc. from polyesters by casting them from a thickened mixture. Any large box store has many on the floor every day.

    This industry has taken a big downturn over the last 6-8 years with many players leaving the market.

    The cost of a sink made with fiberglass tends to be higher and the market won't support it. There is a small market for them in boats and RVs because the cast versions are significantly heavier. Most builders make them themselves for these applications.
  4. rxcomposite
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    rxcomposite Senior Member

    There are many types of these vanities ranging from synthetic stones, cultured marble, or synthetic granite. A low shrink resin is mixed with fillers such as calsomine, aluminum trihydrate (ATH) or granulated granite. Marble like finish is really just a gel coat applied with a swirl in a resin/filler mixture. Others are just tinted clear resin and overcoated with the final color to give a deep hue finish before the resin/calsomine is poured.

    For sinks. you need to buy the plastic fittings for the overflow cavities. The technology is simple and some resin manufacturers gives seminar on how to make this. Competition is stiff as these synthetics are used in fairly expensive hotels, condos, or high rise so you need to produce a really good quality products.

    There is also substantial investment like a fairly large flat solid table with vibrator, a mixing drum with provision for degassing, and plastic edging mold for making molded edge finish. Large pieces are heavy so heavy duty trolleys are needed and a lot of buffing machine. You will be cutting "stones" so a diamond saw is a must.

    Go and check companies that offer seminars.

  5. rxcomposite
    Joined: Jan 2005
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    rxcomposite Senior Member

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