Long hive sides are bowing outwards.

[Bob Wilson]

The first two long langstroth hives I made are warping. They are 4 feet long, one made out of 3/4 inch white pine boards and the other out of 3/4 inch exterior grade plywood.
The plywood hive is bowing outwards in the middle. The frames sit on the frame rests at the two ends, but in the middle section they fall down into the box. If I move a frame towards one side to seat the frame on the frame rest, it falls off the other side. It is very frustrating to inspect the hive.
The pine board hive is also warping some.
HOWEVER... the third box I made was from 2X10s, and it is nice and straight.
Anyone else experiencing this problem?

[BeeMaster2]

Bob,
Since I don?t have top bar hives, I haven?t but what I would do is put a bar clamp acros the top where it bows the most and put a wire strap across it and screw it down on the outside so that the screws are not in the way of the top boards. Use the top boards to determine the best location so that you have minimum interference whit the top boards.
If you don?t have large clamps, I have some you can borrow.
Jim Altmiller

[Acebird]

Put a block in the center of the bow and run a cable around the hive going over each block on the sides.  Use a turnbuckle to tighten the cable.  Protect the corners with a small piece of angle or bend sheet metal around the corners.  Clamping might be helpful initially with the cable as a permanent solution.
As the frames fill with honey the weight could be pushing the walls out.
The clamping method could be permanent by cutting a "U" shape in a sheet of plywood and using wedges between the U and the sides.  Sling the U underneath.

[Bob Wilson]

I have thought of another way of fixing the problem. Since every repair presents problems or interference with the hive in some fashion, I am going to...
1. Build another thick walled 2X10 long lang hive, and,
2. Cut up the problem box into short sections and create 5 nuc boxes out of it.
I think the 4 foot long walls eventually bend due to the natural warp of the wood,the humidity from without, and bee moisture within.
A 4 foot section on 2X10 has less warp and "bendiness".

[Acebird]

I think the 4 foot long walls eventually bend due to the natural warp of the wood,the humidity from without, and bee moisture within.

You will always be plagued with this.

A 4 foot section on 2X10 has less warp and "bendiness".

Not in theory.  If you lay a 6 x6 on the ground it will absorb moisture from the ground only on one side and bow like crazy.  It is the nature of wood to expand and contract by moisture content.  Painting helps by slowing the process down.  Wax dipping would help also but that would be fun on a 4 ft long piece.

[Bob Wilson]

You might be right, Acebird. If the 2X10s warp like the 3/4 inch boards, then I might have to defect to the standard langstroth camp. 

[Acebird]

You might be right, Acebird. If the 2X10s warp like the 3/4 inch boards, then I might have to defect to the standard langstroth camp. 

You might get away with a 1/4 threaded rod configured like a pipe clamp fitted just over the cover on the 3/4 wall.  It would be moveable if you made two sets.  Of course you could buy pipe clamps.

[jimineycricket]

I have some thin-walled nuc boxes that were warped and bulging and could not be lidded very well.  So I braced them with 3/4 x 3/4 stock on the outside and screwed from the inside.  Is it possible that you could expand this solution to fix your larger long hives?

[Ben Framed]

You might be right, Acebird. If the 2X10s warp like the 3/4 inch boards, then I might have to defect to the standard langstroth camp. 

Ace is right. 2Xs will bow as he described. What might help, if you decide  to go that route is painting (sealing) the 2Xs inside and out.
Even though the bees will eventually coat the inside, this will help until their work can be achieved.  In the mean-time, (hopefully),  retarding warpage too a minimal.

Food for thought:
Remember, the humidity will be high inside the hive with bee activity such as nectar drying, moisture exhaust etc., another reason for good ventilation (in this case).

Phillip

[cao]

I have not noticed any bowing in any of my long hives(5 of them).  All made of 2x lumber.  One even got slimed by Shb's with honey running out the front a couple years ago and when I cleaned it up, it was basically filled with water and soaking wet for the whole day.  If you have a good solid bottom fastened to the 2x sides, it will take a lot for the boards to warp.  It  also depends on the quality of the lumber used.

[Bob Wilson]

I suspect so also, Cao. My 2X10s with a solid bottom board screwed underneath is not warping at all. It's only the 3/4 plywood and solid pine. And they are only bowing at the top. I plan on using 2X boards again in the near furure.

[Michael Bush]

I have had the issue.  I screwed a 2x2 or a 2x4 lengthways to stiffen and straighten it.

[Bob Wilson]

Did it work very well, Michael? It would have to screwed from the inside  out into the 2X4 to get a strong hold.

[Michael Bush]

Yes, it has to be screwed from the inside if you are using a 2 by.  It is a pain, but it worked for me.  Keep in mind though that even a two by can warp.  It helps if it's warped slightly n the opposite direction...