Is a 48" long by 12" wide slab cabinet door going to warp?

[Brian Elfert]

I am building some cabinets for my RV. They are long skinny overhead cabinets. I would like to buy or make a 48" long by 12" wide slab cabinet door that is paint grade. I am considering MDF or Baltic Birch plywood. Weight is an issue in an RV so I would prefer to use plywood. Will I have a problem with a door this long and skinny warping? Would it work if I attached some stiffeners to the back of the door?

My other option would be to buy some shaker style doors that have a frame if they will be less likely to warp.

[David Hawxhurst]

i have shaker style door in my rv. i like the look better then flat panels. if you choose flat panel i think you would be fine with baltic birch plywood. you should consider so sort of edging for the plywood.

[Brian Elfert]

My RV is not at all fancy. If I do flat BB plywood doors I would route the edges. I am just painting the cabinets so no need for edging.

My main concern is warping on such a long door. If Shaker style doors would not warp compared to flat plywood I will go that route.

[Peter Quinn]

As long as you seal all sides and edges you stand a fighting chance. There are never any guarantees. I'd use at least 3-4 hinges over that span, which will go a long way towards resisting warping. I'd use BB for reduced weight, or ultraliite MDF if available, perhaps with an 1/8" solid wood edge band to give the edges more impact strength.

[Brian Elfert]

Any other comments/ideas?

[Bill White]

Brian, the shaker door will probably be the best bet. At least 3 hinges for sure.
MDF would be heavy unless ya use the lite-weight stuff. Then you'll have the edges to worry about.
Just my vote.
Bill

[Brian Elfert]

It seems like they make cabinet doors out of MDF all the time. Why would the edges be an issue? I'm leaning towards the shaker style doors as I have no cabinets in my RV right now except a few temporary ones I picked up at a local building materials reuse place.

[johnny means]

Properly finished MDF will do very well in this application. I would stay away from Ultralite, it's very soft and the edges damage easily. I can dig a chunk out with my fingernail. Baltic birch can work also, but can be a little more hit or miss. I do a lot of inset slab doors with baltic birch. At about 50"x12" any deviation from flat shows. Honestly, more often than not, the first piece I grab isn't flat enough.

[scott vroom]

Weight is an issue with an RV, which should eliminate an MDF slab. My suggestion is shaker style with a 1/4" plywood center panel. I'd make 2" rails/stiles from poplar, and use 3 hinges on each o'head door. If the poplar is dry, flat & straight warping will not be a problem. I'm assuming you'll be securing the doors with latches which will discourage warping.

[Bill ThompsonNM]

Weight is an issue with an RV, which should eliminate an MDF slab. My suggestion is shaker style with a 1/4" plywood center panel. I'd make 2" rails/stiles from poplar, and use 3 hinges on each o'head door. If the poplar is dry, flat & straight warping will not be a problem. I'm assuming you'll be securing the doors with latches which will discourage warping.
That sounds like a winner to me. Bound to be the lightest solution. Looks nice and should stay warp free. Can't ask for more.,.

[Brian Elfert]

I will need to buy doors if I decide to use Shaker style doors. I simply don't have the tools or space to make cabinet doors. All I have is a chop saw, Craftsman table saw, a Kreg jig, and a few other tools. I don't even have a router right now. I think I can make some cabinets good enough for my RV with what I have.