I’m in the bidding and planning stages of building a cabinet that will be for exterior use. The cabinet will have some protection from the elements but not completely and be well primed and painted. Even though treated ply would be best for longevity it’s surface will not produce a good finish. If this were an interior cabinet I would simply use maple ply but I’m not sure of its stability to the elements and longevity once the owner assumes maintenance I.e. repainting. I have used ¾ luan primed, painted with oil base, in a similar circumstance but the jury remains out on that since it’s a recent project and I haven’t seen how it will hold up under the full spectrum of elements.
Any suggestions, input etc for a good finish grade ¾ ply for this application?
Replies
Scott
Cant you use MDO plywood, its used for exterior use, I believe it is used to make signs. Its meant to be painted and you can use some 1/4" strips of solid wood on the edges for added protection.
Doug
Doug, I’m not familiar with MDO ply. Can you give more detail?
Jamie, There is the quandary; I need an exterior ply with the finish qualities of cabinet ply, both sides. The best exterior ply I can find doesn’t come close. The supplier where I bought the ¾ luan stated it was made with a waterproof glue, I have to take his word for it since this is beyond my field.
Thanks for the input!
Scott R.
Scott
MDO plywood is made for exterior use, it has a paper product laminated onto the ply, great for painting, that's what its made for. You will get as smooth a finish as you would on birch or maple ply.
Your lumber yard should have it, or at least be able to get it. Even some of the big box lumber yards have it.
I remember building a sign for a sign maker and I'm sure that it was MDO that he had us use.
It comes it 3/4, 5/8, and 1/2", I don't know about any other sizes but I now for sure you can get it in those.
Cost isn't that much more than birch or maple cabinet ply.
If I remember right a lot of plywood is made with exterior glue, but that doesn't make it exterior ply, in the sense that you would want to make exterior cabinets out of the stuff.
You cant go wrong with the MDO, but you have to paint it, because of the paper laminate on it.
Doug
I'm not sure if you know this, but the Formica type countertop surface laminates are made of several ( something like 22 ) layers of fine building paper pressed together with high quality plastic resins to make that hard water resistant surface.
MDO plywood is a high quality fir ply, filled and sanded, and laid over with about 4-6 layers of aproximatly the same material and process. The result is a paper surfaced, water resistant, smooth paintable plywood.
I've used it for a lo6t of exterior detail work. Just this morning, I moved a third of a sheet of left over that was sitting outside the shop for ages - well, maybe three years - being used for occasional temporary worktop over sawhorses for painting or glueups. It has suffered absolutely no problems in spite of extreme abuse.
Like has been mentioned, it is easy to buy, can be had in 1/2" or 3/4" faced on one or both sides, and is about the same price as birch ply.
Another possibility is MEDEX, an exterior MDF. If you are milling someth9ing like raised panel doors or profiled edges and trims, this might be the better choice but it is HEAVY!.
Excellence is its own reward!
Thanks for the input. MDO ply is what it will be then. Scott R.
Use plywood intended for the exterior of a house, like T111 without the grooves. It has waterproof glue holding the plies together; your usual cabinet plywood does not.
Medium density overlay (MDO) is what you need. I paid $45.00 per sheet for 1/2" primed both sides. Any good lumber yard carries this. Spray painting is best, takes several coats to cover well with a brush, more with foam roller.
ANother vote for 2-sided MDO. Iv'e had a few sheets of this outside for several years (a sign), painted, with no ill effects.
The weak spot of this stuff is the edges; make sure to prime and paint themwell.