One last carpentry question (need quick answers please)

[MichaelD]

Last one guys, I promise. At least for this weekend.

As you all know by now, I'm building a large cage (box, essentially) out of 3/4 plywood. Planning on assembling it w/wood glue and nails from a nail gun.

Being the the pieces are all joining at right angles (90 degree), I can't groove-out a full dado (slot), like you would for shelves in a bookcase.

My question is this:

Should I just assemble the pieces as above, OR should a machine a "rabbet joint" on the edges of the pieces first?

Please see the picture labeled "Rabbet Joint" on this page (small pic on the left)

Strength is key, here, as this is a big, big box (84 x 30 x 30)

Thanks much. Tomorrow morning, I build! *Big, Roman-trumpet sounds*

 

[Thrillhou]

The rabbet would probably be stronger than a butt joint. Go ahead and rabbet it. It will make it easier to line up when nailing too.

What kind of nails are you using?

 

[MichaelD]

<< What kind of nails are you using? >>



Thanks for the reply. I'm using 1 1/2 or 2" finishing nails, shot from a nail gun. 90-100psi. Screws are a pain in the butt. Have to predrill all the holes and even then it would prolly split the plywood anyway. Nail gun gets it done in 1/10th the tiem.

 

[Cerebus451]

You can go to this page to see the various ways to join wood as well as the pros/cons of each. Dovetail is the strongest, but unless you have a router and a dovetail jig, they can be very hard to make.

 

[Ornery]

Screw the butt joints and screw the nailer. Just use cleats in the corners and fasten it all with drywall screws. They can be driven in almost as quick as a nail and will be stronger. Also easy to pull apart down the road.

What's a cleat? I'm trying to track down an image, but not having much luck. A cleat would be a 1"x2" (3/4"x1-3/4"), or 1" square piece fastened in each inside corner. You can screw from the inside out if you don't want the heads to show.

 

[MichaelD]

Thanks guys. I don't think drywall screws will work very well in plywood. Now, with subwoofer box built out of MDF, drywall screws work very well, b/c MDF is very similar to drywall, i.e. very powdery, flaky material, but not for plywood.

I do know what cleats are. The problem is that I don't want to take up a bunch of interior space with them. Thanks for the idea, though.

 

[flot]

Ditto - drywall screws kick ass. Put them in with a normal or cordless drill, they have some serious bite to them and you don't have to drill pilot holes. They shouldn't split the wood unless you get too close to the edges (which you may...) But if you use 2x2 or 1x2 in the corners with the drywall screws, the box will be stronger and hold up nicely.

What are you making?!

 

[MichaelD]

I dunno...I have consulted with my buddy who has the woodshop and he said nothing about drywall screws. He's used to building stuff like bookcases, tables/chairs, stuff like that.

I'm building a cage for my biggest boa constrictor. The box won't really be bearing any weight, besides it's own. I.E. it's not going to have steel rods or anything stored in it. It will sit on an already-constructed stand made of 2x4's The stand is 8 feet x 4 feet x 30inches deep. This thing is so strong, that I jumped up and down on it. (literally) and I weigh 215 pounds. (fatass that I am.)

 

[Ornery]

• This is a cleat!

Drywall screws are the standard construction fastener of choice these days. They come in stainless or zinc plated... whatever you want, any length you want.

 

[MichaelD]

<<

• This is a cleat!

Drywall screws are the standard construction fastener of choice these days. They come in stainless or zinc plated... whatever you want, any length you want. >>



Wow, did you just do that in CAD/CAM or something? That's cool! Simple and quite effective. I wish I could draw.

Here's a dumb question: how do you drive the screw STRAIGHT in like that, w/the cleat so close to the panels? Right-angle driver attachment or something like that?

 

[Ornery]

Click the link again, I just updated it.

Hopefully, you'll have a power or cordless screwdriver that can sneak up against the side. If not, screw it at a slight angle, it won't hurt anything. Come from the outside in if you don't mind the head showing. Use glue too, for an awesome joint.

BTW, the back panel is what holds it all square, so make sure to leave it a little loose till that is attached and square.

Edit Drywall Screws! I love 'em!

 

[MichaelD]

I must admit, it DOES look strong. The screws pull against each other, pulling the boards from the outside, in, against the cleat. Nice. Thanks for the nifty mechanical drawing skillz! Thanks much.

 

[Ornery]

My pleasure. If you want to be fancy, you can pre drill the holes in the cleats and even countersink them. The edges can be mitered for a furniture quality edge. It can be as crude or craftsman-like as you care to. If you were building a shipping crate like that, I would expect it to be done in about 20 minutes, after taking 10 minutes to lay it out. Measure twice, cut once, you know?

Have fun!