A or B?

[Coastie]

I am building a flat-bottom skiff using exterior fir AB plywood. Which side is the exterior, the "A" side or the "B"? Does it matter since I will be glassing the bottom? Also, is it customary for the "A" side to have footballs all over it?

Thanks in advance! :confused:

[D Gobby]

Hiya Coastie

Since you are using ext grade plywood it doesn't matter which side faces out.
Ext grade means that it was put together using waterproof glues.
The footballs on one side are where there were knots or defects in that one face that is the A side. The other side with knots and defects is the B side.
If you are going to glass the outside,fill,and fair the B side might be better leaving the clean face on the inside.
Darrel

[NormMessinger]

If you are glassing the outside I'd put the "B" side out. Consider glassing inside also since Fir plywood checks. The footballs will offend.