Door Shrinkage Issues in Refinishing

A cabinet refinisher gets advice on how to limit the problem of wood drying shrinkage causing unstained edges to become visible. September 3, 2010

Question
I refinish about 30 kitchens a year and out of 30 some of the doors shrink and reveal the unstained part of the panel (in the stiles and rails). I usually go back and touch this up. Is there any way to avoid this or stop it from happening? This problem mainly happens on stained and lacquered doors.

Our procedure is as follows:
-Stripping of doors
-Lacquer thinner rinse
-Sanding
-Tacking the top and bottom of panel to the rails if needed
-Staining by hand
-WB sealer
-WB lacquer
-Shading
-Two coats of lacquer

I've tried everything from bradding the panel to spot gluing the panel in place but nothing seems to work. It seems that when the panel wants to shrink there's no stopping it. Please keep in mind that this does not happen to all the doors - maybe one or two out of the whole kitchen.

Forum Responses
(Finishing Forum)
From contributor C:
When staining dip a rag in the stain and using an air nozzle blow stain into the crack between the rail and panel. If the panel shrinks at least it will be the same color.

From contributor K:
There are a lot of variables here. If you are using water to rinse the doors after stripping, it would be best to let them dry out for about three days. If you put the stain on sooner, and the door panels continue to shrink, the unstained wood will show, so you may well have most of the doors drying, but the two or three might be a problem because they are being handled differently. They are at the last of the stripping batch and therefore not getting as much drying time, or they are being put in a part of your shop that doesn't allow them to dry as fast.

Contributor C's approach works, but there is still the same problem with the finish - as the panel shrinks, the finish edge will start to show. If you can, get the doors to dry to a similar moisture content as would be inside a house. Possibly putting them in an air-conditioned room in your shop (cooler air holds less water vapor than warmer air).

Another thought comes to mind, again assuming that you are using water rinse: throughout the drying process are you rotating the doors to get an even drying process? If you have a compressor, use it to blow out the water in the in the voids.

Your words, "It seems that when the panel wants to shrink there's no stopping it," is absolutely true. Pinning, bradding, etc. will not stop the expansion/contraction of the wood with changes in its moisture content. The forces at work are greater than the strength of the wood fibers to hold together. Even under constraints, the wood will move, and the area(s) of least strength will give way. Once the drying has been completed, a finish will act as buffer, slowing the movement down. But it is not totally eliminated.

From contributor G:
Contributor K has it. I would add that overdrying the doors would shrink the panels to their minimum and all subsequent movement would be expansion and would tend to hide rather than expose the unstained part. If however the panels are loose and the edges are exposed because the panels have slipped around then you are on the right path by pinning the sloppier fit panels in place, after they are dried and before staining.

From contributor B:
I'd say you may not want to tack the panels. If they'll move around when you�re staining by hand that's a good thing. You'd be able to work stain under stiles/rails with a stiff brush. The same thing goes with your first seal coats.

I wouldn't tack/pin the doors until after the final coat and I didn't mean to imply that you should use a brush to work any finish under the rails/stiles while you�re sealing the doors. That could mess up your stain. If the looser panels moved pretty well you could slide the panels around while you�re applying the first seal coats.

From the original questioner:
Great tips - thanks guys! I've done all of the above though even to the point where I place the doors in the staining room which is 35% humidity but I still manage to get one or two doors than need touching up. Not a major thing but still a pain in the butt.