Yes, absolutely veneer both sides especially if you are using real wood veneer (ie the 1/8" you are talking about). In my opinion 1/8" is still too thick as a veneer, you really want to get down to below 1/16".
It doesn't have to be the same species, either, ie for hidden areas you could use poplar veneer to save some $$.
I always try to lay the veneer so that the grain is running perpendicular to the substrate, this way the veneers counteract each other in terms of wood movement. The cross-grain situation is good enough to hold each other tight, but not strong enough (thickness under 1/16") to crack.
Also, I wouldn't secure the veneer with the pin nails. You will have to sand the piece after you veneer it and if you use the pin nails they will make sanding problematic, and also show after the veneer is sanded down.
That being said, a closet would be a really, really obnoxiously sized piece to do using thicker veneer. Not to discourage you, but just some things to consider as you are still early on, since you only have the ply broken down:
1) Do you have a large vacuum press? Pieces of that size would be very, very difficult to cold press properly. You will see problems at your veneer seams, and also if you don't press properly I guarantee you will see bubbling.
2) Is there a particularly good reasons to be using real wood veneer on this, over a high quality walnut ply? I can see a rationale if you are doing some thing like book-matching or grain matching, but you can also do that with commercially available veneer (which is much easier to apply without a vacuum press, just contact cement or cold-press glue). The other rationale is if you are using some very very expensive wood like rosewood or cocobolo, where the extra time investment makes financial sense.
3) What glue/adhesives are you planning on using? I've veneered small-width pieces with cold-press glue but for veneer of that width you'd almost have to go with a urea-formaledhyde glue to ensure you don't get any glue creep (happens with most PVA glues). Those are nastier glues to work with and also certain individuals have allergies to formaldehyde- especially since this piece is going to be in an enclosed indoor area, it will continue to off-gas.
4) Time... do you have the patience to joint, resaw, joint/drum sand, (repeat multiple times), sand the veneer, rough cut the ply, seam the veneer, spread the glue, press, sand the seams, finish sand, finish cut the veneered ply?
Personally if you wanted the look of real wood, it would be more cost efficient to do it with solid walnut, no kidding. On the veneer work that I have done, I would think the total time investment was at least 3 times that of what it would take me to do the same thing with solids, and probably 6 times that of what it would take me to do with a appropriately faced commercial ply. I would just get a good quality DOMESTIC walnut plywood (Murphy?) and attach a face frame. You can ask for bookmatched (not rotary cut) face veneers if you want.
5) Last consideration, substrate quality. Since you are doing the veneer yourself, the ply can do all sorts of crazy things as you lay it on. Remember your veneer work will only be as good as the bond for the face veneer of your substrate. Even if you can stick your veneer on, if your substrate veneer peels off....
You absolutely need the best ply that you can get. Ply that is flat and will stay flat (try putting glue on the face veneer of cheap BORG ply and see what happens). IMO there are only two choices- Finnish/Russian/Baltic birch (13 ply), or domestic Appleply. Figure $60-$70 for a 5x5 sheet of BB, and $120+ for 4x8 ApplePly.
You can also look at MDF (very, very glue hungry, and iffy when it comes to water contact), or MDF core ply.
Good luck, let us know what you decide on doing.
alfa said:
Festoolfootstool said:
Hi
You will need to veneer both sides of any of your ply to keep it straight.
That's something I need clarification on:
Will it still be necessary to veneer on both sides
if the plywood is 3/4" AND the walnut is
