Storage cabinet door bowing

The left door on a storage cabinet that I built recently has suddenly developed a vertical bow, making the hasp/latch difficult to latch. When I hold a straight edge vertically along the right side of the door there's about a 1" gap between the straight edge and the door at midpoint. The left side of the door has no bow. The right hand door is not bowed.

The door is approx. 23-3/4" (width) x 66-1/2" (height), made with T-11-1 siding and framed with 1x4 Douglas Fir fastened using wood glue and deck screws. I primed and painted everything prior to assembly.

 

Do you have a question?

 

I'm wondering what caused the door to warp/bow and if there's a way to fix it without having to build another door.

 

66 1/2" is a pretty long door. Generally if that was a raised panel door, it would be broken up into 2 sections, with 3 rails. I assume your door only has 2 rails... top and bottom, so it can pretty easily bend in the middle.

We also don't know what your T1-11 is... some is 5/8" thick plywood... some is 7/16" thick fiberboard, some is 5/16" thick cement board. None of them are guaranteed to remain flat... plywood probably has more of a tendency to warp than others.

And then your 1x4 can warp. Yes, painting can help control/reduce that but it's not a guarantee that things won't warp. If you glued a painted surface to a painted surface, you might not have gotten a good glue bond.

Only way to figure out which one bowed is to disassemble it. And I would say that when you rebuild, glue bare wood to bare wood, clamp it flat for 24 hrs, caulk joint perimeters with painters caulk, then prime and paint all sides.

And your 1x4 frame should probably have an additional middle rail, it would provide more glue area and strength.

Long doors often also need an astragal between doors or a backer board behind one of the doors to keep them aligned when shut.

 

Common problem with that size door and T111. I anticipated that problem when I built my shed. I used a "Z" support on the inside section.

 

@ XLSleeper The T-11 siding is 5/8" plywood.

The door has 3 rails, top, bottom and center.

I pre-painted everything before assembly so yes it's possible that the glue bond is poor, however I used screws to attach the framing so even if the glue joints were bad I wouldn't have expected the door to warp, at least not this soon. I did clamp everything for over 24 hours after gluing and screwing. I didn't use caulk, but the climate in this area is very mild and the door hasn't been subjected to a lot of moisture.

The side of the door that's warped has an astragal strip screwed to it which was cut from an 11/16" piece of exterior grade plywood. I'm wondering if the strip might be the source of the bow. Guess I'll have to remove it to find out.

@ Norm201 I was thinking about framing the backside of the door to give it a little more strength and hopefully pull it straight. If I take that route I'll most likely use "Z" bracing.


Thanks for the advice/suggestions.

 

The 3/4 backing really isn't really heavy enough to prevent bowing. As you found out its kind of a crap shoot... 50:50 at best. I have built many shed doors using 2x2s behind the plywood and even then some of them have bowed.

 

I'd initially considered framing the back of the door with 2x4's but decided not to because of the weight they would have added. I'm about to start framing the back of the door with some leftover 1x stock that I have. If that doesn't do the trick I may try using some angle iron.

What ticks me off is I spent a big chunk of money on the T-11 siding mistakenly thinking that it was better quality than the cheaper siding material that's available. The non-grooved, rough sawn siding is much cheaper and seems to be just as good, qualitywise, as the T-11. And the porous nature of the grooves on the T-11 made painting them a pain.