View Full Version : How to calculate airspace for fiberglass box?

02-18-2006, 11:29 PM
I want to make a sealed fiberglass box and I was wondering how exactly do I calculate the airspace? I know for a box it's HxWxD then divide by 1728 (If I remember correctly) and you get your airspace.

02-18-2006, 11:31 PM
IIRC, 28 liters of water is 1 ft^3...

02-18-2006, 11:31 PM
water in liters is the best way

02-18-2006, 11:32 PM
for a sealed box its not very crucial. if the box dosent have any odd shaped faces you can calculate it like a regular box, i dont think the thickness of glass would make much of a difference in sealed. i know one way to find the volume is to fill it with water after your done making it. usually then you would calculate the port length, but again i dont think thats nessesary with a sealed box.

02-18-2006, 11:33 PM
I usually make my "shell" or back first, usually a little bigger than what i am going to plan to use. then i measure out packing peanuts in a 1 cubic foot box and pour as many as you need into a garbage bag. take the bag and place it in the shell and you can kind of shape the bag to how you want your box to look like.
i dunno if that makes any sense.

02-19-2006, 03:53 AM
good work ;)

02-19-2006, 09:12 PM
If you want to know after its built. Packing penuts will get you pretty close. Find you a cardboard box. Calculate internal air space of cardboard box. Fill fiberglass box with nuts. Then take the amount in fiberglass box into cardboardbox. It will get you close enough for a sealed box.