"Experience is that which enables us to recognize our mistakes - the next time we make them."
Due to the good humor of the site they also have a conversion for 'apples to oranges'.
This is a link with some basic information on the various grades of plywood and the differences in them.
There is not anything more toxic about the glue used in exterior grade plywood than that used in interior. There are plenty of woods as well as treatments to wood that you do need to be aware of. Treated lumber. many woods themselves are toxic. But plywood is not one of them. If plywood was toxic I woudl have expected to have seen it recommend that you where a respirator when cutting it for that specific reason. I have never seen any such recommendation. I have frequently seen them in regard to cutting treated lumber. It is true that lung protection is recommended for cutting of any wood due to the risk from saw dust. The warning about toxicity is specific when it exists.
Thanks Daniel Y for clearing that up for me. If you look around many manufactures use it on inner covers, you probably just don't recognize it. I get exhausted from all the arguments on this site, especialy the ones that could be avoided with a little research. They do make PT plywood but that is not what I am talking about.
Last edited by beehonest; 11-26-2011 at 06:37 PM.
All beekeepers can agree on one thing, and that one thing is, that all beekeepers can't agree on one thing.
another way to convert any measure is Google, just type what you know and the unit you want to know
I've used old cupboard doors for inner covers. They have an outside frame that can be cut down to size, the center inset piece is thin enough to cut an oval hole in it. The difference between the frame and the inset is my bee space. I have several of these made from smallish cupboard doors purchased at ReBuild for about 50 cents a piece. I've also cut notches out for bee entrances on some of them.
I'm using 1/2" CDX (I think, I was planning to buy 3/8" CDX and the sheet I selected turned out to be 1/2" when I started cutting it, so it was on the wrong pile) for both telescoping and inner covers. I figure the extra thickness won't hurt, and my brother's bees REALLY glue stuff down. His Kelley covers come apart when being pried off, so I plan to set the plywood into a dado with about 1/8" of rim on one side an at least an inch on the other. That way we have a bit more room over the frames for things like protein patties, and the wide side will work nicely for a candy board or insulation.
The nice thing about making your own stuff is that you can make anything you want! The bees won't care unless you violate bee space, in which case they will build comb or glue it up for you.
I don't recommend inner covers thinner than 3/8" though -- too likely to warp with condensation in the winter. I think the bee will appreciate the extra wood overhead, too, so long as you have ventilation, it's more like their normal homes.