Replies

1. 
   hack123 | Mar 04, 2006 05:35pm | #1

   I don't agree with the notion that poplar likes to move, I always use it where I need stability and freedom from excess movement, notwithstanding questionable moisture content and the cardinal sin of finishing only one side.  In a door of that size, I would divide the panels with some additional rails for increased strength and stability if possible but it's the one sided finish that did your doors in.

1. 
   knc | Mar 04, 2006 07:10pm | #2

   Thanks for the input.  I agree

2. 
   JohnWW | Mar 05, 2006 03:17am | #3

   Those are large doors for a 3/4 inch thick frame, especially with no intermediate rails.  No matter how you made the four corner joints, the door assembly wouldn't be very stiff and would warp easily if the wood in the frame or the panel started to move.

   There are three possible explanations for what is happening here, the problem is probably a combination of all three.

   1.  The wood in the frame wasn't straight grained and possibly had some reaction wood in it, and, as the frame has adjusted to the moisture levels where it is installed, the wood has warped.  For frames this size anything other than carefully chosen quarter sawn stock would be likely to cause trouble.  Poplar isn't an especially unstable wood, I don't think the fault is with the choice of species, but rather in the choice of the individual boards.

   2.  If the doors are freshly painted on one side only with a water based paint, then one side is temporarily much wetter than the other and warpage is to be expected, this will settle down after the paint has dried and the moisture in the stock has evened out, but the door may be permanently racked.

   3.  Even after the paint has dried, the interior and exterior faces of the doors will be gaining and losing moisture at different rates because only one side is finished, again causing stress on the frame.  Finishing the unpainted side of the door will solve this problem.

   Under the best of circumstances, with meticulous care taken in choosing the wood, and then building and finishing the doors very carefully, I still think that these doors would be likely to warp at least a bit, it's a structurally weak design.

   John White, Shop Manager, Fine Woodworking Magazine 

   
   

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   Edited 3/4/2006 7:20 pm ET by JohnWW

1. 
   knc | Mar 05, 2006 05:20pm | #4

   Thanks John. We needed a good text book explanation on what is needed to make a cabinet door warp. I am going to remake those doors (eight of them). I just needed to explain to the designer, the painter, the General and me, that together we were able to create warped cabinet doors.

   Edited 3/5/2006 9:29 am ET by knc

1. 
   JohnWW | Mar 05, 2006 05:38pm | #5

   Glad I could help, good luck with the new doors.John