priming aluminum

[3rdday]

Whatever you do, do not use a polyester gelcoat. It is hydroscopic.

[BigLew]

Whatever you do, do not use a polyester gelcoat. It is hydroscopic.

I'm sorry, but I am not familiar with "hydroscopic." Hydrophyllic and hydrophobic yes but, Hydordroscopic no. What does that mean? Maybe, water will penetrate through it?

[Blue_Heron]

I'm sorry, but I am not familiar with "hydroscopic." Hydrophyllic and hydrophobic yes but, Hydordroscopic no. What does that mean? Maybe, water will penetrate through it?

Couldn't find "hydroscopic", but how 'bout this:

hy·gro·scop·ic
adj
Definition of HYGROSCOPIC
1: readily taking up and retaining moisture
2: taken up and retained under some conditions of humidity and temperature <hygroscopic water in clay>
— hy·gro·scop·ic·i·ty\ noun

Dave

[3rdday]

yes, you are correct, I fat fingered the "d" in lieu of the g. Hygroscopic. Ovviously, choose the polymer that is least hygroscopic. Or, one that is most hydrophobic.