voids in plywood?

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Rex R

LV2
Joined
Apr 21, 2010
Messages
6,392
Reaction score
383
so what do you do when your nice laser cut 1/4" plywood fin has a void? was doing some sanding of the leading edge of the fins for my phoenix when I found a void, thought no biggie I'll fill that with spot putty latter...well latter came around. was about an 1/8" wide, one ply thick and an inch or more deep. I squirted some white glue into it then jammed two (flat) toothpicks into the hole. then trimmed them off. I will fill any remaining holes with spot putty after the glue dries and have sanded the toothpicks to match the leading edge.
Rex
 
oh, just a wee bit. middle ply of 5-ply plywood(didn't feel like whittling one down to fit). toothpicks can be used for all sorts of things :), including picking at stray bits of food.
Rex
 
That can really piss you off when you find one in a sheet of 3/4" Baltic Birch that you paid $55 for. I occasionally make speaker cabinets and you want the highest quality plywood for a speaker cabinet because a void causes rattles in the cabinet. No one wants a $150 speaker cabinet to rattle. It's bad enough the bastiches started coring the birch with poplar and just use a veneer of birch...bogus. Sometimes I look around for a while but amazingly most of the time Home Depot has the good stuff. I have caught them punking out but for the most part they've been honest, more than I can say about "specialty hardwoods" sellers....
 
Elmer's wood filler- work it on, let it set, and sand.


Mark Koelsch
Sent from my iPhone using Rocketry Forum
 
That can really piss you off when you find one in a sheet of 3/4" Baltic Birch that you paid $55 for.

I've paid that much for 1 sheet of 1/8 okume marine ply, [the whole 4x8 weighs 28# ] but then it has a Lloyds of London Register guarrantied voidless mark. :)


Richard
 
As a general rule, either 'aircraft' plywood or 'marine' plywood is specifically built up so as to not have voids.
 
Can marine plywood be found at boat shops?

Yes; but it's also available at any decent Lumber supply or Building material supply house.
Marine Grade Plywood's are normally A/A grade meaning both exposed surfaced are top quality finish...meaning expensive but for most applications where inner ply voids are to be avoided worth the price. 1/4" thick and below are very hard to find, I'd check by phone or on-line before venturing around town to locate a stocking source.
 
Had a similar problem with the last six sheets of 1/4 inch plywood I bought at National Balsa wood. I too used flat tooth picks.

Andrew
 
Usually I find voids in the cheap Home Depot/Lowes Birch hardwood ply which is like 45 bucks a sheet (last time I bought it that is). Interesting they are advertising it as domestic now instead of the import stuff they used to have, its still pretty much crap. I buy mine from a wholesaler and its true baltic birch iirc like 15ply for 3/4 inch (and less than $45 per 5x5 sheet). I usually deal with void the same as most people, inject glue and a chunk of wood to fill the void. Usually with big box home stores the problems been delaminating, once again inject glue via syringe and clamp tightly.
 
Back
Top