wood

[grdev]

This week I found 3/4" Doug Fur in 10' lengths at Menards for a little over eight dollars each. Today I found Marine grade 1/8" PLYWOOD FOR $61.95 FOR 4'X8' SHEET AT WWW.HOVERCRAFT.COM  IN Rockford, Il.  I plan to glue the tong and groove DF flooring boards together with T88 to maximize the useful wood in each board. there is a groove cut in the center of each board.  I'm able to drive to each place and save the shipping charges.  Still debating on whether I should down size the DF for the spar caps, they are stronger than Spruce, but a little heavier, but not sure how much weight I would be adding if I use same size.

[Steve]

This week I found 3/4" Doug Fur in 10' lengths at Menards for a little over eight dollars each. Today I found Marine grade 1/8" PLYWOOD FOR $61.95 FOR 4'X8' SHEET AT WWW.HOVERCRAFT.COM  IN Rockford, Il.  I plan to glue the tong and groove DF flooring boards together with T88 to maximize the useful wood in each board. there is a groove cut in the center of each board.  I'm able to drive to each place and save the shipping charges.  Still debating on whether I should down size the DF for the spar caps, they are stronger than Spruce, but a little heavier, but not sure how much weight I would be adding if I use same size.

Not to overlook the epoxy weight in the glue up - convert the spar callout to board feet and use the published material weights... Question: does that flooring have any preservative in it that would change glue performance?...

How many ply's does the plywood have compared to aircraft stuff?

[grdev]

The wood is just machined, kiln dried wood, no preservatives or other coatings. Just full of splinters. I have an email into Hovercraft asking for specifications on their plywood. They do have one model hovercraft with wings. I will inspect  edges of wood very carefully before I glue.

[grdev]

Steve the plywood is Okoume Marine grade plywood with water & boil proof glue with equal thickness ply's.
Do you think it will be OK?

[Steve]

The wood is just machined, kiln dried wood, no preservatives or other coatings. Just full of splinters. I have an email into Hovercraft asking for specifications on their plywood. They do have one model hovercraft with wings. I will inspect  edges of wood very carefully before I glue.

DF has a brittleness factor that needs to be tested for by breaking samples... With some Googling you will find reports regarding high stress felling events with resulting mill material brittleness...

[Sam Buchanan]

I have plans-built two aircraft with wood wings. I did not cut corners when it came to spar material. Whatever $$$$'s were necessary to guarantee the best/approved wood was willingly spent on spar caps. There are far better places to try to save a few bucks than the sticks that keep the wing from folding up.........

[Bob S.]

Yeah, maybe ribs, gussets, intercostals, fillers here and there for the DF....but I'd go full length Sitka Spruce for the spars without a doubt!! and only AC Ply for the spar webs!! This ain't no boat and the stresses ain't the same! Your butt will be in the air...not floating on some calm lake somewhere..