Using an autoclave is only to enhance a cure properties which is needed
in this  this application. The resins I mentioned Cure in average
temperatures.  Pardon me for this, but it's "ultimate thinking" that
seems to dump onto innocent Vanagon mods..  These are workhorse utility
vehicles that are best modified with simple executable ideas.  For this
purpose, either a cosmetic skin, if the guy wants the look, put on a
layer of CF and wet it out. Why break his back or piece of mind with
big procedure. For the DIY topper, they don't "autoclave" boats or
anything else in this size for mass  public consumption.  Today's
vessels and like parts are  vacuum bagged, but not all,--but  the
driving motive is reduction of styrene exposure to workers and emissions.

Another  fact: bagging and autoclave require panels to be built with
extra material to insure stiffness, since thinner, and yes stronger/
lighter panels,  carry the undesirable feature of being flexible.
Stiffness in panels is expressed  2x Thickness = Stiffness Cubed  or 8x
stiffer for every doubling of thickness, which means that thinner panels
become 8x more flexible for every halving of thickness.

So I left the autoclave out of this one.  If a person wants the vacuum
bag route, be prepared to Not  notice the difference in service in this
application. 90 ft sq of wet out would be for the  4 layers would be
just ten gallons of resin.  This would likely be in the 60 percent glass
and 40 percent resin ratio using a hand layup. If that were bagged, you
could see 70 percent glass and 30 percent resin. so about 100 ounces,
say gallon less resin. The part would 8 lbs lighter.  Cost more though
and take more time.  Bagging will leave a slightly smoother finish on
the surface.  A air pressure vacuum can be purchase for $100.  It uses a
venturi and is used occasionally in the shop where I train.  Otherwise,
this time and cost to bag is a wash to just sand and fair one extra
time, that the bag saves.

Mark

  Jim Arnott wrote:

> Where's the cost of renting the autoclave to cure it all?
>
> Jim
>
> On Sep 9, 2007, at 7:21 PM, Mark Keller wrote:
>
>> Well I priced 50 in cloth at 37.50 a yard.  weight was 5.7 oz per ft
>> sq.  Basic Van  is 15 x 6 feet, or 90 ft sq so this give us 10 yards
>> approx or $375 for the cloth.  The wet out could be done at .75 oz per
>> ft sq or 90 oz so a gallon of resin. at $100 or $150 for epoxy resin
>
>
>