# Best plywood to use for stand construction?



## kroner19 (Mar 18, 2012)

Hey fellow TPT do-it-yourselfers,

I'm planning on constructing an ADA style stand for a 60-P and was wondering what would be the best type of plywood to use. I see from some other members projects that all different types of plywood was used. But which one is the best? I would think that marine plywood would be the best for this type of project due to its water resistance. Should I pay almost 3x the price for the marine ply? Is the Formica alone enough protection for the wood against water damage? Can I get away with using a different type of ply (prefinished, obx, mdf, veneered ply, etc.) and seal it prior to laminating it with Formica? Also, what thickness would suffice to hold the 60-P? My first thought would be to go right for the 3/4" for its rigidity but I'm open to suggestions. 

Anyone who has had any bad experiences with a particular type of plywood (warping, buckling, expansion, rot,etc.) please let me know. And the same goes for those of you with good reviews. Please post what type of wood you used, any specific sealers/lacquer you might have used, Formica that you found matched ADA's pretty closely, any tips, hints, or problems you might have encountered during your project, or anything you would've done differently if you could go back in time and correct, etc. 

Money is tight so any mistakes or poor engineering decisions that you may have made and I can learn from/avoid would be extremely helpful. 

Ill conclude by telling you that I was and always will be a carpenter at heart and currently I am an iron worker by trade. I possess enough knowledge in design and construction to easily complete the underlying "cabinet" with professional quality however I have never had to construct something to be water resistant/ waterproof. I also have never worked with Formica. Never did a job that required it. Anyone in the building trades, or the weekend do-it-yourself-er can tell you that you will never learn everything there is to know about a particular trade but you must be willing to learn and absorb something new everyday. That being said, this ADA stand will be my self-lesson in wet area, waterproof cabinetry with a small lesson in laminating and routing Formica. Always learning. 

Sorry for the lengthy post for what seemed to be a simple question. In my head I just constructed the whole project and these are the questions I was left with. 

Thank you in advance,

Mike


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## GraphicGr8s (Apr 4, 2011)

You don't need marine plywood. Any good cabinet grade plywood is good. Birch is fine but it's about the same cost as oak plywood down here at the BBS. Stay away from the construction grade stuff. There aren't enough layers and there are voids in the plys.


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## kroner19 (Mar 18, 2012)

Should I use 3/4" or 1/2" plywood? or a combination thereof? And, should I construct the whole cabinet and then seal/lacquer it prior to applying the glue for the formica?


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## GraphicGr8s (Apr 4, 2011)

I use 3/4" for my cabinets. The back is rabbeted into the sides and is generally 1/4" But I sometimes use 1/2"
Seal the inside first. At least that way you won't get any on the laminate. Even thoug you're going to laminate it use proper construction joinery. Bottom gets rabbeted. I'd even go so far as using tongue and dado joints.
Don't seal where you're going to put the laminate


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## Hoppy (Dec 24, 2005)

An aquarium stand doesn't need to be waterproof, or even very water resistant. You obviously won't be dumping water on the stand, and any small spillage will dry quickly enough to prevent it from affecting the plywood. I used birch veneered plywood for all of the stands I built, mostly because I found that all other plywood was already warped in the store, usually Home Depot. I can't even remember the last time I saw a sheet of plain fir plywood that wasn't warped. I see no reason to use 100% birch plywood - baltic birch/finnish birch/russian birch. They are just too expensive for what added value they have.

Another good material to use, even though many people don't believe it, is MDF. That, of course, is assuming that you really get MDF and not particle board. It is very flat, very hard surfaced, sometimes much cheaper than birch plywood. It does have disadvantages - special techniques are needed for joints, it is very heavy, so the stand is very heavy, and it can emit formaldehyde fumes until it is sealed. But, I always liked making cabinets with it.


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## GraphicGr8s (Apr 4, 2011)

I've gotten a lot, and I mean a lot of oak plywood at both HD and Lowes. I've never found a straight, flat sheet. We have a local small lumber supplier here and the prefinished plywood was warped too. I had to search through hundreds of board feet of solid 3.5" x 1" x 8' to find fairly straight stock. Most of the time I had to cut around the warp, cup and twist. 

As for the other statement you made Hoppy, look at the sink cabinet in the kitchen. That sees more water than a tank stand. And even the MDF holds up for a while. The better cabinets are made of plywood and they hold up fine. Yeah. I know I'm agreeing with you. Get over it


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## Husker13 (Mar 23, 2012)

I built all of my kitchen cabinets with 3/4 cabinet grade plywood, what ever you get (oak, birch, maple, etc) it is all going to have the same material on the inside - random wood. What you need to look for is the number of plys and grade of plywood core. For ultimate strength and durability I prefer Baltic Birch plywood. I have found that it is relativly inexpensive, a 5/8 4x8 sheet should be around $50. If you want 3/4 cabinet grade plywood should be about $30-$40. Just look hard wood suppliers or cabinet suppliers.

As for assembly I would not use rabbets or tongue or dado. I only use pocket holes and screws, no glue is needed and it is a lot faster. Every strength test I have seen done on pocket screws is that they perform as good or better then a dadoed joint. Kreg makes a lot of neet kits for this.

I would seal the inside of the cabinet with paint, and silicone the joints. I have seen to many store bought stands fail because of leaks.


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## GraphicGr8s (Apr 4, 2011)

Husker13 said:


> I built all of my kitchen cabinets with 3/4 cabinet grade plywood, what ever you get (oak, birch, maple, etc) it is all going to have the same material on the inside - random wood. What you need to look for is the number of plys and grade of plywood core. For ultimate strength and durability I prefer Baltic Birch plywood. I have found that it is relativly inexpensive, a 5/8 4x8 sheet should be around $50. If you want 3/4 cabinet grade plywood should be about $30-$40. Just look hard wood suppliers or cabinet suppliers.
> 
> As for assembly I would not use rabbets or tongue or dado. I only use pocket holes and screws, no glue is needed and it is a lot faster. Every strength test I have seen done on pocket screws is that they perform as good or better then a dadoed joint. Kreg makes a lot of neet kits for this.
> 
> I would seal the inside of the cabinet with paint, and silicone the joints. I have seen to many store bought stands fail because of leaks.


Oak and birch 3/4 plywood down here is about $45/sheet. they don't stock 5/8 in anything except construction grade. 
I use both pocket screws and dadoes. Each has its advantages and its disadvantages. It all depends on the situation. My personal preference is the dado. I've also done pocket screwed dadoes. The advantage in a shelf or cabinet bottom (in reality another shelf) goes to the dado however. With a properly made and glued dado the wood itself fails not the joint. That's borne out in independent testing. Don't know anyone who would say a pocket screw alone is stronger depending of course on the joint being made. The advantage to pocket screws is no clamping time. 
Now if you're talking about using a butt joint instead of a dado then yes pocket screws are much stronger than glue or edge screwing since pocket screws go in to face grain and not edge grain. 

Siliconing the joint is a waste of time. Use a good glue. If you apply poly over the cabinet it's like adding a laminate to it and it's pretty much sealed. About the same with latex paint.

Don't get me wrong though. I've gone through literally thousands of pocket screws. I love them. But every joinery technique has its place. Of course if time is no object then M&T is the only sure way to go. And yeah I use biscuits too. There is absolutely no more strength in a biscuit joint then in a straight glue up. But they do make alignment easier.


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## Hoppy (Dec 24, 2005)

GraphicGr8s said:


> I've gotten a lot, and I mean a lot of oak plywood at both HD and Lowes. I've never found a straight, flat sheet. We have a local small lumber supplier here and the prefinished plywood was warped too. I had to search through hundreds of board feet of solid 3.5" x 1" x 8' to find fairly straight stock. Most of the time I had to cut around the warp, cup and twist.
> 
> As for the other statement you made Hoppy, look at the sink cabinet in the kitchen. That sees more water than a tank stand. And even the MDF holds up for a while. The better cabinets are made of plywood and they hold up fine. Yeah. I know I'm agreeing with you. Get over it


OMG, does this mean I'm wrong?????:icon_mrgr


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## GraphicGr8s (Apr 4, 2011)

Hoppy said:


> OMG, does this mean I'm wrong?????:icon_mrgr


Doubtful. How could you possibly be wrong if we agree?


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## kroner19 (Mar 18, 2012)

Lots of great info here. Thanks everyone. Now some questions about Formica. I haven't looked for any yet but I'm assuming it comes in 4x8 or 4x10 sheets. In order to keep the pieces more managable, would I cut it down to maybe 1" bigger all the way around whatever side im working on prior to gluing it on routing it to size? If so, can a circular saw be used if the finished side is face down? Or would using a straight edge and router be better?


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## Hoppy (Dec 24, 2005)

When I was using those formica sheets I found it was very hard to work with. The sheets are very "floppy", and will crack easily if allowed to bend too much. Also, cutting it can and will chip the finished surface, possibly add a few cracks to it. The best way I found to make it manageable was to set up a sheet of 3/4 plywood on sawhorses outdoors, to give good support to the whole sheet. I did most of my cutting from the back side, and used a hand jigsaw with a hacksaw blade, as I recall. I did no more cutting than necessary before gluing it to the cabinet. This did waste some formica, but kept breakage to a minimum. When I had to pre-cut, I cut about 2 inches of extra material all around, to keep any cracks from extending to the good surface. At times this worked like a charm. Other times I hated working with it.


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## GraphicGr8s (Apr 4, 2011)

Formica generally comes in a larger sheet than plywood. At least at the HD here it does. You cut the sheet on a tablesaw with a zero clearance insert and a blade designed for laminate. The sheet is cut about a 1/4" larger and is trimmed to fit with a laminate trimmer after it is glued. You use contact cement on both surfaces and it's allowed to tack up. You put dowels on the glued surface and put the laminate on the dowels. You line up the edges as best you can and start pulling the dowels out. You work from the center out. Then a J roller is used to put the laminate in intimate contact with the wood. Trim with laminate trimmer. You can also use a bastard file to smooth it out but the cabinet shops use laminate trimmers. You could also use a full size router with a laminate trimming bit.


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## cobra (Feb 4, 2005)

kroner19 said:


> Lots of great info here. Thanks everyone. Now some questions about Formica. I haven't looked for any yet but I'm assuming it comes in 4x8 or 4x10 sheets. In order to keep the pieces more managable, would I cut it down to maybe 1" bigger all the way around whatever side im working on prior to gluing it on routing it to size? If so, can a circular saw be used if the finished side is face down? Or would using a straight edge and router be better?


I trimmed my sheets down with a Harbor Freight sheet metal power sheer. Cost $45 bucks and it went through the formica with ease.


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