vac pressure for 1lb eps

General Discussion
1

ok so i put poplar perimeter rails on my friends 9’ foot board, i did two 1/4" pieces around the outer edge on each side. after that i put the whole thing in my vac bag and sucked everthing down. i pulled between 6 and 7 inhg after every thing cured i noticed wrinkles in going vertical near the nose and tail in the foam witch it looks like it was crushed slightly from the pressure. from my experience i have not had happen but i have never worked with 1lb eps. i guess it could be the foam or just to much pressure. the foam i bought came from a supplier in baltimore witch is where im from. it was advertised as dock flotation but its virgin eps not reground. its cuts really nice with a hot wire and sands very well also. so i if anyone has answer it would be greatly appreciated.

                    will

born in a garage raised on a beach

2

I use -0.1 to -0.15 bars and this avoids 1 lb EPS being crushed.

3

ya i was really surprised to see this happen but after sitting out of the bag for a while the ends of the foam started to come back to there previous shape, and everything is pretty much back to normal. my gage could be off but i doubt it. ill be doing another compsand but with balsa on my 6’ fish. but im only going to pull about 5 inhg this time and see what happens. really thats all the pressure i need to press the rail in place and the deck. i also have been thinking since the poplar is much stiffer than balsa and even though i was bending 1/4" rails around the perimeter and i was putting so much pressure on the rails for them to stay put that could be a reason why the foam started to compress.

born in a garage raised on the beach