Guys guys guys..... before you go any further, read the safety advice on these products. Polyester resin (used for fibreglassing and as a solvent in the car body filler) is very damaging to ur lungs and theoretically carcinogenic. Not only should u be using in a well ventilated area, you should be using a proper ventilator mask. Not a cheap 2-3 quid paper mask, not a 10-20 quid particle dust mask, but near industrial grade dust and organic fume masks. Cheapest ones in uk I have seen are at least 25 quid and upwards. Dont play around w ur health!
I have built 1 or 2 things, halfords upol cannisters are cheaper and just as gd as isopon