Cabinet of “white wood” cupping badly
Joe Sullivan
| Posted in General Discussion on
IN the course of trying to improve my skills and build storage at the same time, I build an 8 ft tall tool cabinet out of edge-glued “white wiood” (maybe pine) from HD. I dadoes in the shelves. It lookes reasonably good given my skill level, and stores my stucc — but now some of the individual boards are cupping and causing real problems. I may not be able to hang cabinet doors, and some shelves may become unstable.
I guess the wood was wet and dried unevenly.
Is this common?
Can I do anythng about it? What about hanging damp rags in the cup and seeing if the foders will swell back?
Replies
If you used wet wood for the cabinet it just has to dry to the point where it is in equilibrium with the prevailing conditions there.Did you fit the shelves into grooves/dadoes? And how have you joined the carcase at the corners?
Hanging wet rags etc will not be of any use as a permanent solution.
I reckon you should just sit back and observe at your leisure what happens when you use unseasoned timber. Measure some widths and make some marks as a reference on how things are now and compare what happens in the future. It is not as if the shelves are going to fall out of their grooves.
Philip:
You are very kind to answer so many of my blockheaded questions.
What I did was to make each side out of three nominal 1x6 boards at the bottom, with one two full width shelves. The cabinet then cuts back welsh dresser style to a single 1x6 for about 2 feet to give clearance for outfeed from the bandsaw and drill press which are on either side of the cabinet i my 11x 22 foot shop. ABove the cutback area, the sides are made of two 1x6s.
The bottom shelves are dadoed in, and braced by nominal 1x4s back and front which are mortised into the sides, glued with Gorilla Glue, and nailed with finishing nails.
The upper shelves are dadoed in , and glued only with no mechanical connection except that the shelf back, made of birch plywood, is screwed on.
All the shelves are fine, but the boards on the upper part of the sides are cupping and breaking the glue joints. Not only does this concern me, but i was in the process of fabricating doors with extensive racks for chisels and other tools, and obviously if the front boards are cupped, any doors I put on will not close properly.
Had also considered using wide strong clamps to bring the boards true, and then fitting over some wooden braces to keep them straight.
Joe, I wrote the first response, went for some food, came back and re-read it-and thought I would delete it as it appeared a bit off-hand:then saw your reply-glad you did not take it negatively.
I think there is nothing you can do other than to let it settle down-it could take a couple of seasons, then you will see what can be done to neaten it up. The boards are cupping because they are shrinking- if you try to stop this you could have cracks instead of glue joints separating.Make sure air can circulate inside as much as possible to lessen the cupping.Philip Marcou
I'm having a little trouble visualizing what you are describing but it sounds like you may have some cross grain situations with the shelves. If shelves are dadoed and glued into the sides, they can only be glued if the end grain of the shelf is butted into the long grain of the sides. If the sides of the shelves are glued across the grain of the sides, then you will get the type of situation you describe.Can you post a picture?Howie.........
NO digital camera at the moment, unfortunately.
Think of it this way. 1x6s go full length, floor to ceiling. Dadoes cut across the grain hold the shelves. The shelves are butted into the dadoes and glued on the ends.
The shelves are flat and fine. It is the uprights that are cupping, and pulling away from the shelf-ends.
I think you can clamp the verticals back in place and screw them into the shelves, countersinking the screws just enough to have room for plugs to hide the screw heads.On the other hand, if appearance is not important here, you can avoid the countersunk screws in favor of getting a bigger 'bite' in the soft pine.pins
Joe,
The reason for your problem is that Home Depot white wood is not dry to the extent of furniture grade material. It was meant for framing houses. It will continue to shrink and warp until its moisture level matches that of your shop. That could take several weeks to years. I would suggest putting the cabinet together with screws, not glue. You will eventually have a few open joints, but probably nothing will break apart. Shrinkage is far greater widthwise and thicknesswise than lengthwise. Any dimensions controlled by long pieces will shrink negligibly. Remamber that as you build the doors which should probably be frame-&-panel style. Good luck.
Cadiddlehopper
Indeed so. I did not relaize just how wet construction lumber can be, and mistakenly thought that all would be well with some that I had bought several weeks before cutting, but it was not so. That was the first of several miscalculations it would seem. Live and learn.
Joe
If you are not to fussy, apply an assembled face frame of kiln dried furniture grade wood. Screw the frame to the carcass without any glue and through slots rather than holes in the face frame. Hang your doors to the face frame (not inset in the frame). Since you will have (most likely), many visible screws in this cabinet, once stable, countersink them enough to fill flush, and sand well. This sounds like a good cabinet for a paint finish. JL
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