question about a cabinet construction

[Susumu Mori]

Hi all,

I don't have much experience with sheet goods, but I need to make a cabinet with 32 (horizontal) x 30 (height) x 15 (depth) with two large drawers (32 x 15 x 13) and a laminated maple counter top (33 x 16 x 1).

My question is the carcass construction. I can cut a 3/4 birch plywood to 30 x 15 for the sides and connect them with 32 x 6 x 3/4 cross members; may be two at the top, two in the back and two at the bottom. This would create a carcass of 32x30x15 and I can hang two large drawers and put the counter at the top. To hang drawers, we need sheet surfaces only at the sides, right? So, I think the top, back, and the bottom don't have to be full sheet to save $.

1) Do you think this carcass would be strong enough if I screw the two back cross members to the wall? Or do I need a 32x30 backboard (like 1/4 plywood) for rigidity?

2) Should I use a full 32x15x3/4 sheet at the top and the bottom instead of the two cross members? I believe the weak point of this construction is the sheering force from the side. So, the backboard would be more important than the top/bottom reinforcement? But if the back cross members are screwed into the wall, the sheering force is no long an issue?

3) I'm thinking about simple butt joint for the cross members to the side boards using a couple of Domino. Would you recommend rabbet or dado for stronger carcass?

I would appreciate your advises!

Thanks,

Susumu

[John TenEyck]

Susumu, with no offense intended, I think you should buy a couple of books on cabinet construction before you start cutting wood. There you can read why cabinets are constructed the way they are and see diagrams of how the parts fit together. It very much sounds like you are just starting out; as such, it's better to learn the right way of doing things to minimize frustration and disappointment. Here area couple of references you may want to consider.

http://www.amazon.com/Illustrated-Cabinetmaking-Construct-Furniture-Woodworker/dp/1565233697/ref=sr_1_4?ie=UTF8&qid=1406920011&sr=8-4&keywords=cabinet+construction

http://www.amazon.com/Complete-Illustrated-Furniture-Cabinet-Construction/dp/1561584029/ref=sr_1_1?ie=UTF8&qid=1406920011&sr=8-1&keywords=cabinet+construction


John

[Mark W Pugh]

I just went through this learning/research phase myself. I read a crap load of books, watched the internet to the end, and asked for advice on here. What I decided to do was follow this guy's building techniques. The carcasses are strong and fit together nicely.

https://www.youtube.com/watch?v=Apd_Hc5wr0s

One of the most critical points is to ensure you think out your cutting list. You want to cut out like dimensions all at the same time.

[Susumu Mori]

yeah, that has been always my problem; do first and fail. At least I asked help this time here:)
Thank you for the suggestions of the books. I do have a fair number of books for solid wood furniture and I have made a few pieces of desks and chest drawers in the past, but the sheet good cabinets seem to have quite different construction mechanisms; support by lines and faces. I went through some Youtube like Norm's videos and some carcass drawing in the internet, but still a bit loss about the degree of strength we can expect from different ways of construction....

[Mark W Pugh]

yeah, that has been always my problem; do first and fail. At least I asked help this time here:)
Thank you for the suggestions of the books. I do have a fair number of books for solid wood furniture and I have made a few pieces of desks and chest drawers in the past, but the sheet good cabinets seem to have quite different construction mechanisms; support by lines and faces. I went through some Youtube like Norm's videos and some carcass drawing in the internet, but still a bit loss about the degree of strength we can expect from different ways of construction....

If you get a chance, just take at look at the videos I posted. I just built mine and everything was made with butt joints. No glue, just screws. I used 4" wide stretchers, and I added a 1/4 back for looks, not rigidity. Mine are PLENTY strong. Remember, cabinets will be attached to the wall, which will hold the cabinets rigid. I can't remember if I read it or heard it, but cabinets are cabinets, not playground equipment.

[John TenEyck]

The principles of design are the same whether the cabinets are solid wood or sheet goods. The joinery may change, but they both must fulfill the same requirements. Read a book on kitchen cabinet construction if you want to see specifically how sheet goods cabinets are put together. Go to a furniture and look at how their cabinets are put together. Really look. Then go to Home Depot or similar and look at the kitchen cabinets display, and do the same over in the bathroom vanities section. Open up the doors and drawers and really look at how they were constructed. You'll learn a lot.

John

[Jim Matthews]

I'm a hack, so take what I tell you at face value.

There's so much I don't know about this topic,
but that didn't dissuade me, either.

******

To get the dimensions right, build the face frame (or mockup from cardboard) first.
That will allow you to set the proportions and work out where everything
goes together. It will also illustrate where you might have collisions or obstructions.

I built my bathroom cabinet in much the method you've described, and it's rock solid.

I rabbet the "side" panels to provide more glue area along the front seam where the panels join.
I still apply molding to cover the joint, as exposed plywood edges can be damaged by rough handling.
(If you've got kids, you'll get dings and dents - 'wrap' the edges to prevent flaking of the plywood.)

There are very few screws or fasteners, as the modern construction adhesives make them redundant.
You'll need clamps to hold things in place, but little else.

I used the Loctite brand of "quick grab" adhesive to secure panels in place.



294063 294064

If you build from the wall outwards, you'll always have a solid point to anchor the assembly.

Worked for me, anyway.