How Deep to make Dado for 1/2" Panel 27"x 14"

[sofa_king_rad]

I was going strong on my first project, then we had a baby and I've barely touched it in nearly 7 months. NEEDING to get this done i've start scheduling time each week for it.

It's a twin sized bed frame for my daughter. I have the footboard frame roughed out, domino'd and ready to sand and glue EXCEPT for the 1/2" plywood panels that will go on the inside. I have a couple questions.

Should I do a rabid cut on each side all the way around the plywood? I don't see any benefit in this other than being able to cut a smaller groove in the Rails and Stiles, which are like 2.5" thick, so it isn't necessary. I can just cut a 1/2" dado, right?

So for the panel, it will just float in the grooves correct? How deep should the groove be, I have plenty of room. Is 1/4" normally enough or should i go 1/2" or even more? I haven't cut down my plywood yet, but the panel opening are about 14" x 27".

Hopefully i'm explaining this correctly. This all would have been easier had I just found some plans we liked and did that, but we didn't and I'm building on my on design, simple as it may be.

Again this is my first project.

 

[gunnyr]

I typically make grooves for 3/4" panels 3/8 deep.  If for no other reason than it makes the math easy!

 

[sofa_king_rad]

and should i oversize the plywood panel by 3/8" on each side, or just short to leave room for expansion?

Is there a size of panel when expansion isn't really an issue, or does it always need to be accounted for?

 

[semenza]

and should i oversize the plywood panel by 3/8" on each side, or just short to leave room for expansion?

Is there a size of panel when expansion isn't really an issue, or does it always need to be accounted for?

You won't need to worry about expansion with plywood.

Seth

 

[ear3]

With the frame members so thick, I think it's fine to just use 1/2 dado. Keep in mind though that the plywood is slightly undersized, so you may want to investigate a 15/32 bit. Expansion won't be an issue, but I typically cut mine around 1/16 short (in total, so 1/32 on either side) to make fitting and glue up easier.

 

[Jesse Cloud]

Since this is your first project, you might consider cutting your plywood first and checking it for square (compare two diagonals, if same then probably square, if not investigate where size difference is).

That would leave open the opportunity to tweak the depth of the dado to hide any off square issues.