Critique my Cabinet Design...be Gentle

[Gore]

I realize that as I type this, that a picture would probably be helpful, so maybe I'll add one later, but I think you can visualize what I am saying.

Also, I already build 7 cabinets this way, so it's a little late to be asking this, but I plan to build more.

I built several wall cabinets following this plan:
1. Use 3/4" mdf for all sides, including full back (maybe overkill for the back, but I can add mounting screws anywhere this way.

2. Cut 3/4" dadoes, 1/4" deep, 1.5 inches from top, bottom, and back (making the back of cabinet 3/4" from wall, except on edges.

3. Cut the same dado on the back panel, so the top and bottom shelves sit in a dado on all sides.

4. Glue/screw/nail all pieces together.

5. Face frame is the standard primed fj pine at big box stores, top rail is 2.5, sides and bottom are 1.5", which makes the bottom of ff flush with bottom (shelf) of cabinet, and flush with bottom of sides considering the dado ends 1.5" from bottom/top. 3/4" overhang on sides, 1 3/4" on top.

My doubt comes into play when I consider the added benefit of a full thickness back panel, and if I am losing too much interior space by cutting the dado where I do. I lose 1.5" of depth on a 12" cabinet. I did this to account for any evenness in the walls, but I may have gone overboard. I could cut a rabbet on the back of the cabinet and use only 1/2" material, and gain an inch.

Also, since these cabinets are 12" x 24" shop cabinets, I don't put any shelves in them, but I think I may add some later.

 

[bergheger3]

Design sounds good.

I use plywood for the carcasses because MDF has a tendency to swell when it get any type of moisture on it. I really like using prefinished maple. I then pocket hole the carcasses together.

Your face frame idea is good. I like the look with the rails being flush like you mentioned.

You can pre drill shelf pin holes prior to assembling the carcass. For the shelves I’d use plywood not MDF.

 

[mike93lx]

I avoid MDF if at all possible. Sure it is easy to work with and consistent but the dust is terrible and it can't handle any water.

I would use plywood and get rid of the dados. Rabbets are plenty strong, more forgiving and a lot easier to cut. 3/4 works for the back, but its more than needed. 1/2 is plenty, sometimes 1/4 is as well.

 

[hawkeye2]

On my cabinets I used 4” x 3/4” plywood top and bottom rails for the back.l and left the rest of the back open.

 

[Jeff Ivers]

My experience with mdf is on purchased metal framed shelf units that had mdf shelves. I found the mdf tended to swell and warp. I have replaced most of those shelves with 3/4 plywood, which I find to be much more durable. With regards to your construction technique, the advantage of the full thickness back which is dadoed for the shelves is more support for the shelf and resistance to warping. On my built cabinets I have sometimes skipped a back and other times used 1/4 plywood set into a rabbit. On backless cabinets, I have notched a 1/2 into the sides at the top and the bottom of the cabinet to provide mounting flexibility.

 

[Terranova]

Not to mention. 3/4 mdf is heavy As F. A full back, yes. 3/4" is overkill.

 

[JonBoehman]

I build cabinets regularly for custom built ins and remodeling. 1/2" birch ply would be more than adequate for the box structure of a wall cabinet. A rabbit joint in the back for 1/2" or even 1/4" backing would suffice just as long as you used some 3/4" x 2" for the stiffening brace to attach the cabinet to the wall. 3/4" MDF is going to be a lot of weight on the wall and not only that but to lift it into position to mount. MDF also doesn't take glue very well due to the nature of its makeup and will come apart if it gets wet.