The blanks I have are done really well with 1/8" basswood stringers on the glued up ones while the others are split with good straight cuts… those could be flexed some up or down before gluing up stringers which I have done with both basswood and PVC material. 1.5 to 2 lb density. Knowing exactly what density EPS is more an edcuated guess than exact science.
Anyone else interested in getting some of these, I’m open to doing so. Like I said, I got them at a liquidation price and can let them go for a bit more than the shipping box and freight charge.
talked to the guys at ShayZeus.com a while back about getting some custom EPS blanks. never ended up ordering, just got too busy but they said it would take about a week and I think it was $60 per blank. they’re based in Portland.
Northwest Foam in Wilsonville has big blocks of EPS. But as McDing has pointed out, making your own blanks from block foam is a process all in itself. I do my own only because I can’t get 1# blanks I need for composite any other way. If you are just starting out, buying a close tolerance blank will save tons of grief and get you in the ballpark much simpler.