solid oak V groove door problem

[Dominique Meuris]

We have made a kitchen for a customer with solid oak cabinet doors.

We have contructed them in the following way.
A 2 cm thick frame on the back, with a middle rail. Frame width is 6cm.

and on the front of the frame we glued 8mm thick planks with grooves in it.

But now all the doors have started to bend in the middle.
How does this come and is there a way to solve this?

+ for in the future, what is the best way of constructing solid oak cabinet doors with V-grooves? without using a frame + panel

[Lee Schierer]

Can you provide a photo or sketch of the construction? I suspect that the construction does not account for seasonal wood movement due to ambient air moisture changes.

My father replaced the original doors in their kitchen with Knotty pine doors to match the rest of the woodwork in the house. He made the upper doors and they have worked great and never bowed or warped because he made them in a way that let the individual boards move seasonally. He passed away before he could make the lower doors and my mother hired a guy to make them for her. His doors did not account for wood movement and each winter they curl up and each summer they flatten back out and will actually close. In the winter the are curled partially open.

[Mark Bolton]

The best way to construct these in the future is to not construct the in them first place. You say this is for a customer yet you've violated the first fundamental rule of wood construction?

A balanced glue up with thin veneers laid up on a stable core (edge banded) would be a start.

Doing this with solids is a well known recipe for disaster.

[william watts]

What you are describing is cross grain construction. The natural expansion/contraction of the front panel is restrained by glueing it to the rails at each end and in middle. Construction should allow for wood movement, thats the point of frame and panel construction. Marks advice to not do these doors in the first place is spot on. Do whatever is neccessary to keep your customer happy, you will benefit in the long run.

[Jerry Miner]

You can do this if the front panel is made up of individual boards (I would T&G them) instead of a glued-up panel, so the boards can expand/contract individually without warping the door. I would probably attach from the back with screws, rather than glue---but if the boards are narrow enough, you might get away with gluing them.