Pine panel doors, expansion/contraction

[Jeremy Patrick]

Hello,
I wanted to ask what people have to say about spray finishing panel doors, like a six panel pine door and expansion/contraction.
I have sprayed a few doors now, but I always seem to find that after a few years or even just a few months, After the door expands and contracts with the seasons, I will see a lip of finish were the edges meet as I was spraying it at the time.
wanted to ask how people have spray finished panel doors like this, and not had the type of seam/cut off build up when a panel expands/contracts

[Curt Harms]

Spray the panels before assembling. I see this with a closet door that we bought assembled but bare wood. It doesn't swell/shrink too much but it's noticeable between the seasons.

[roger wiegand]

+1-- finish the panels prior to assembly, as with any other frame and panel construction.

[Jim Becker]

Yes, the best way to help combat that is to prefinish the panels at least through the first top coat of the finish before final assembly of the door or other construction if your rails and stiles are subject to seasonal movement in a meaningful way. Some door construction is less susceptible to this, such as veneered lamination on composite substrates that don't move much.

[John TenEyck]

Or perhaps your question relates to pre-made doors? The best approach I know of when that's the situation is to finish them when the humidity has been low for some time, like late Winter where I live, so that they have shrunk as much as possible. Then when they expand again the panel will expand into the frame and won't reveal any paint gaps.

One thing to keep in mind about painting pre-made doors, try very hard not to create a fillet of paint where the door meets the panels, especially if painting them when the humidity has been high high for some time. If the panel gets welded to the frame, it's likely to split when the RH goes down. You can tape off the panel from the frame, and then the frame from the panel and finish each separately, or you can finish it all at once and then blow any excess paint out of the joint with compressed air before it sets. Taping off takes longer but is more likely to give better results both technically and aesthetically.

John