How do you keep a cabinet frame square?

I am making a china hutch in a Mission style. The top part is separate from the buffet and is near completion, but I have not yet glued it up. It is approx. 53" wide by 46" high. The sides are 4/4 divided light windows, the top and bottom are frame and panel solid 3/4" oak, and the back is 3/4" frame/divided light for mirrors.

I am not worried about the back as the frame squares it up perfectly. The front is only a narrow outside frame with two 7/8" by 1" divider/stiles which will house 3 divided light doors. I am working with the flattest surface I have, but I have noticed that even a little pressure to the top corners will push the frame out of square.

Is there an accepted method for dealing with this flexing? I have seen cabinets with a solid immovable door in the middle, but I don't really like that idea. Is it acceptable to have to shim the bottom to get everything at 90 degrees once you bring it inside to a less than flat floor? Any suggestions would be appreciated. Hopefully, it will become ridged enough once I glue it up.

Thanks, Dan

I have attached a photo for reference (Yes my shop is a mess.)

Once you attach the back the front will become much more rigid and may not need any additional reinforcement. The glass or other panels you will put in teh back will also stiffen the carcase.

P.S. Put the back in place and clamp it at several locations. You will see an immediate difference in stiffness.

If the front doors are going to be inset, then you are going to need something for them to stop against to keep them properly flush to the case. The ones that I have built have a 2 - 3 inch board that runs the width of the cabinet at the top recessed the thickness of the door. This provides a solid stop for the door and adds stiffness to the front of the cabinet. I do not see this on your cabinet. Of course if these are overlay doors, then as Gilda Radner used to say..... Never Mind!

BTW: It this cabinet of your own design? Or it is based on a purchased plan?

Looks too late for this project, but when I want to make certain one stays square in the field, I use lap joints on the face frame. Stronger than any other way, and even with the small frame you would stay square.

Dan, both the rigidity of the back and taking care to set up the unit plumb and level will work to keeping the front opening square.

The doors will be inset. The two shelves will be glass, so I was going to incorporate a small corbell on each side under the glass to support it at the outside corners. I may try to make one to act as a stop at the top corners of the doors. I will be using a little brass catch (the ones with two balls and peg.)

The cabinet is my design, although I found much of the style ideas on various other mission furniture. That's my biggest problem, designing the major parts first and waiting till I'm done to worry about the small details.

Thanks, I may use a small strip across the top. That might look better.
Dan

Dan,

I think you're worrying too early, as Lee said the back should prevent racking, so wait and see what happens after you glue up. Looks great so far.