Breadboarding (sort of) box corners - Woodworking Talk

Muskoka · 12-25-2007, 05:00 PM

I'm building a blanket box from 3/4 inch cherry.

Instead of rabbetting the corners, I want to create a vertical corner piece and dado the channel for the side and end panels. That will leave each corner with two dadoes with the panels at 90 degrees (obviously).

The trick is, how do I attach the vertical corner to the panels and not have the whole thing blow up when the panels expand perpendicular to the supports?

Thanks for any advice you can supply.

Darryl

**TexasTimbers** · 12-26-2007, 11:10 AM

If I can visualize what you are saying, and I might not be, I don't see a problem. You aren't describing a breadboard "top" but side and end panels.
Just leave enough room in the dados for each panel to expand. You don't have to concern yourself with longitudinal shrinkage because it's so negligible (just leave about 1 1/16" on each end), so if you orient the grain in your boards in your panels horizontally, like most blanket chests, you only need to plan for expansion/contraction room in the top dado. you can put small lengths of felt or foam strips in the bottom dado to keep the panel from bottoming out but also leave room to expand (compress the felt or foam) if the expansion were to get severe due to an unplanned long term exposure to moisture etc.

Make sure your dadoes are wide enough to accomodate the radial expansion (for flatsawn lumber) to keep the panels from spliting the frame along the length of the frame member. I gues this is the blow out you are asking about? Glue some meduim density foam strips between the back of the panels and the inside of the frame members dado to keep the panel pushed against the frame, so no gaps can bee seen from the outside of the chest.

If you aren't describing a floating panel design as I visualize though, I need pictures or else you need someone else who "see's" your description better than I do. I am not very good at that.

if this is not your design intent, just remember that the general design rule for any solid wood panel in a dado is to allow the panel to expand and contract within the dado without the panel ends ever becoming visible when the shrink, and without them ever running out of room to expand.