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Oct 08, 2004, 07:17 PM
Registered User
CT, USA
Joined Feb 2002
217 Posts
Quote:
 Originally Posted by davidfee As a good friend says, "Time to fire the engineers and start production." -David
As an engineer, I take offence to that comment. Just for my own edification, I want to see a breakdown of the material cost. I'm not considering molds, pump and whatever else you need to buy once.

So epoxy is what, about 9 lb/gallon? Let's say you've got a 20oz plane and a fiber fill ratio of 60%, so that's 8oz of epoxy. Let's say you waste a bit and use a 16 oz. That's .11 gallons. If the epoxy is about \$80 a gallon, including hardner, that comes to \$9 worth of epoxy, lets say \$10 with shipping.

Wax is relatively free.

Ok, on to the graphite. 3k is about 6oz/yd^2. and about \$22/yd^2. So carbon is about \$4/oz. 60% of 20oz is 12 oz. soooo that's \$48 worth of carbon. You would need say \$12 worth of peel ply and breather.

So for an all carbon jobbie, your total cost would be \$70, again assuming you have the mold (this is where the problem is), a pump (~\$300 for a kit), AND assuming you buy in small quantity.