2/8/2026 Note: I originally posted this blog on LumberJocks back in April 2017. I m re-posting it here so I can eventually remove it from there.
Do you know how easy tasks sometimes turn out to be difficult, and vice versa? Here's one case where that occurred.
The cabinet's back panel is just a simple slab of wood 3 1/2" high with a 3/8" cutout routed across most the top (it stops 6" from each end, so it s U-shaped) to form a slot for cables exiting the cabinet. At least that's what it was supposed to be
I had planned to cut the back panel and drawer faces from a single 8" board. When I ripped that board in half, I ran into two problems. First, my wife disliked the half I intended to use for the drawers. (It has some charcoal-like mineral stains that look like smudges. I liked it, but she didn't.) Second, that half of the board twisted after I cut it, and I couldn't think of any good way to flatten it. I had to scrap that half of the board and reserve the other for the drawer faces. Now I needed a new back.
The only other usable piece of wood I had left was a 3" wide cutoff from the back edge of the top panel. But it too had a problem. It wasn't twisted, but it had a pronounced bow. If I placed it face-down on my bench, the ends touched, but the center was about 3/8" off the bench. The lumber yard is about 45 minutes away, and I really didn't feel like driving out there to buy a new piece.
After stewing for a while, I had an idea. If I cut the board in half thickness-wise, I could glue the halves back together (with one flipped upside down) to cancel out the stress causing the bow. At this point, I really wished I had a band saw, but I didn t. Fortunately, my table saw has the capacity to make the cut. I was able to clamp a board parallel to the fence on the feed side of the blade to keep the bowed board as straight as possible as I made the cut.
It turns out that most of the stress was on one side of the board. One of the new, thin boards was nearly flat, while the other was more bowed than before.
The good thing is that the pieces were now so thin that it took almost no pressure to flatten the bow. When I glued the two halves back together (even though I stupidly forgot to flip one over), the resulting board was close to flat.
Now my only problem was that my new back panel was too narrow (just over 3" instead of 3 1/2"). I solved that problem by gluing short, thin strips to both ends of the top edge. That worked out fine, with a bonus. I didn't have to rout the cutout; the strips created it for me.
With all of that done, I now had my back panel. I just needed to round off the inside edges to make it easier to insert and remove. I also needed a way to attach it to the case so it was secure, but removable, with no visible fasteners. I've used small magnets for speaker grills before, so I decided to use them here.
I ordered a set of 3/8-inch diameter by 1/8-inch thick neodymium disc magnets from totalElement.com. I used 16 magnets in all: two on the back edge of each inner case side and divider, plus matching ones in the back panel itself. Each magnet sits in a shallow hole from a 3/8" Forstner bit, glued with epoxy.
These magnets are strong! They hold the panel in place very securely. I didn't need to use as many as I did, but I'll never worry about the panel accidentally falling out (and the slight amount of remaining bow is a total non-issue). Removing it is slightly inconvenient, but I can reach my fingers through the 2" cable management holes in the bottom panel and press the panel outward far enough to grab it.
The end result is very clean. (Note: this photo is post-finishing. I installed the magnets after finishing, but thought it was better to describe everything about the back panel here.)
Using the re-sawn panel had another benefit. I had not planned on recessing the back panel, but the thinner panel (about 5/8" thick instead of the planned 3/4") created an inset, and I think it looks better that way (and the shadow line hides the fact that the panel is not perfectly centered due to my magnet holes being slightly mis-positioned).
