Question on attaching cabinet top to under frame....

[George Bokros]

I am making a cabinet for the wife. My design has an frame at the top (like a dust frame in a dresser). The top will set on top of that and be attached to it. My plan is to attach the top to the under frame using screws. I think the best way is to only attach it to the front and back rail of the under frame to allow for wood movement. The cabinet is being made from sugar pine and the under frame is poplar.

I could also attach to the side pieces of the frame if I elongate the screw holes in the under frame, do you think that attaching it to the side pieces of the frame is needed?

Thought and opinions are welcome.

Thanks

George

[glenn bradley]

Depends on the client for me. Folks who realize you shouldn't pick a dresser up by the top, I use 4 figure-8 connectors. Folks I'm not sure about I add something more substantial. If you are connecting to the front and rear of the frame I assume the rear rail is floating on tenons to allow movement. If the top is to move independently of the frame you could use screw up front and screws through elongated holes at the side and rear. In a nutshell I think 4 is enough.

[Jim Matthews]

I would use the screws as you've indicated in the rails that aren't likely to move, seasonally.
I'm lately holding loose cabinetry together (so that they may be disassembled and moved)
with industrial strength velco fasteners.

You align the two parts, place both strips of velcro on the upper piece and press down.
Simple, and a built in dust barrier.

I can't speak to how the adhesive will react to the finish, over time.

http://www.velcro.com/Products/Adhesive-Backed/Heavy-Duty/Industrial-Strength-Extreme.aspx#.Uv0gGPldVIo

[Ken Fitzgerald]

In my pieces, I typically attach it at the front with screws and then enlongate the holes for screws in the middle and back and screw it down. Then, hopefully, theoretically, the distance the top extends of the front of the cabinet will stay the same while any wood movement will take place towards the rear.

[John T Barker]

I'm going to answer with some assumptions in mind. My training was such that I would have the grain of the sides running up and down so the frame you mention should have pieces running crossgrain to the sides. Yes? I hope these are connected to the sides to allow movement as well. That being said every piece I've ever seen or made has attachment along the sides. A lot of people go for overkill in this area which pisses me off when I have to switch out a cracked top (I do furniture repair at a retail furniture store) and put in too many7 screws to hold tops down. I would put two screws in each side if it is 15 to 20 inches deep, one if it is less. It is pretty easy and they should be elongated holes as well.