# Plywood for bottom boards - Experiences



## Jim_in_PA (May 17, 2016)

Exterior grade plywood should be no issue. I use scrap sheathing, as a matter of fact, for bottom boards I've built. I see no need for 3/4" material for bottom boards, either. The stuff I use is nominal 1/2", but really ~7/16". Most plywood today is actually metric thickness, but in the US we still seem to want to stick to Imperial measurements and terms...but have to take into account actual thickness if we're building something that needs to fit together closely. But that's a "religious" discussion best left for other venues. The bottom line for your question remains if it's exterior grade plywood, it will last. If it's interior grade plywood, it will likely delaminate quicker than you will appreciate.


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## My-smokepole (Apr 14, 2008)

I like to use a 2x4 with a rabbit cut out for the sides. With tiebond 3 glue. And a band across the entrance. So that all edge are covered by wood. I make them more like a pallet as a single.


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## snapper1d (Apr 8, 2011)

3/8" ac plywood will last for years and years. 3/8" ac fir plywood if you can get it will last a lifetime if painted.


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## orthoman (Feb 23, 2013)

3/4 AC plywood is my preference. Definitely painted. Have not had one fail yet.


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## spunky (Nov 14, 2006)

Thanks for the replies 

regards
Brad


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## Michael Bush (Aug 2, 2002)

The plywood will outlast one bys in my experience. You can paint the outside with copper naphthenate if you want.


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## frustrateddrone (Jan 31, 2015)

All end grain, dips and knot holes coated with painters caulk and then painted will give a longer life.


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## appalachianoutdoors (May 16, 2015)

Go to Lowe's or home Depot, ask to get 18-20 of the boards with a grove in it that lumber is stacked on. Try to match ones with similar depth groves. Take them over to the plywood stacks, and match a plywood to the groove depth in your board. You have to play with dimensions a little, but you can make a lot of bottom boards made this way from a sheet of plywood. And cheaply if a forklift has damaged any corners.


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## Vance G (Jan 6, 2011)

All my bottom boards and tops are made with 1/2" and 3/8" plywood and scrap 1by. Paint the outsides well and soak the feet on the bottom boards with the copper naphthalene treatment and they last long enough to recoup the $2.50 it costs to build them.


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## Bdfarmer555 (Oct 7, 2015)

I use 1/2" ply, cdx, for my bottoms and tops. Wax dip, have no issues after several years


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## spunky (Nov 14, 2006)

Thanks for the ideas

regards
Brad


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## Vance G (Jan 6, 2011)

A further thought on plywood bottom boards. Every time I go help someone with the circa stone age complicated bottom entrance 'system', I love my cheap, light and easily attached with 2 nails antique migratory bottom board.


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## jcase (Jul 30, 2016)

Got these plyqood ones from shastina millworks, coated with a polyurea coating. Haven't tried them yet.

Most of mine in use now are 1/2inch plywood and are working well.


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## heaflaw (Feb 26, 2007)

What about using burnt cylinder oil instead of copper naphthalene?


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## crgshhn (Apr 6, 2015)

spunky said:


> I inherited some plywood next size down from 3/4 " . In
> stead of having to buy some 1xs to make bottom boards : I was wondering if anyone had any tricks to making plywood last more than a few seasons ?
> 
> regards
> Brad


I use 5/8" plywood stamped "Exposure 1". It is scraps that I get really cheap from a farm supply store. I fill any voids on the edges with a Titebond 3 and sawdust paste, let it dry, then paint edges and exposed side with 3 coats of exterior paint. I've built bottom boards, telescoping covers, inner covers, and nucs out of this. So far, so good.


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