As a fresh-from-the-womb woodworker, I have a glaring need of a workbench and a power tool organizer, and I don't have a lot of space. So, I want to make a cabinet big enough to hold several power tools, with a work surface on top, and locking casters on the bottom. I expect to build a "real" workbench down the road, but I need something to get me started, and I need some help with the design to make sure everything is sound. Since it's my first project I want this to be as inexpensive as possible, but not something that's going to fall apart!!
It starts with a 3/4" piece of plywood for the base, with four casters (not shown in the pictures) screwed into the bottom. The two side panels sit on top of the base, nestled in 3/4" rabbets. Would it be better to do a 1/2" rabbet on the base instead, along with a 1/4" rabbet on the sides, to form kind of a lap joint? (Is there a real term for that?) I would secure this joint with glue, and use screws (from the bottom up) to help hold it in place initially. The back panel would be 1/4" plywood, and would sit in a 1/4" rabbet cut from both side panels and the base. Again, this would be attached with glue, and probably an 18 gauge brad nailer. The face frame would be glued and nailed to the front edges of the two sides and the base, unless there will be a problem with movement?
You can see from the fourth picture that there isn't a lot of "face" for the work surface to sit on top of. Will I need to shore that up? If so, how? Approximate outer dimensions of the carcass, including the face frame, are 36" x 23 1/4", and the work surface is 40" x 28". I don't want a central support in front, because the two shelves need to be able to slide out. How would you attach the top?
I'm also thinking about making a bigger work surface. How much of a lip would you guys leave? Right now I've got two inches all the way around; is that enough to clamp on to? I like the 28" depth because that will fit through most doors, but since this will probably always be in a garage it likely won't matter if I go bigger. At the very least I was thinking about extending one end another eight inches or so in case I want to add a bench vise later, or some shelves/hangers on the side.
My final questions (for now!) are regarding materials. I will probably prime and paint everything. I've seen a lot of people use a double layer of 3/4" MDF for the surface. If I use that, I would have enough left from the sheet to make the doors out of MDF too. Thoughts on that? What kind and grade of plywood for the carcass, and is there a good way to make sure what I get from the lumber yard is flat? What about for the face frame (poplar, maple, birch)? Last, since the face frame extends inward, the shelf slides need to be effectively shimmed as well. Can I just stack and glue a couple pieces of plywood together, making sure the screws for the slides go through plywood faces and not the edges?
I apologize for the length and number of my questions; there's a lot of self doubt going on here! I expect a lot of learning by doing, but the more advise I can get up-front the better off I will be. Thanks everybody!
Edit: Okay I lied, one more question. The shelves are 32 inches wide, but only 21-22 inches long. Will that be a problem? I've read that slide manufacturers recommend that the width not exceed the length. One shelf will hold a router (two bases); the other will hold a circular saw, power drill, random orbital sander, and maybe 1-2 other power tools. All in plastic cases.