I've built many speaker boxes over the years but I'm not very proficient in cabinet making. One of the tasks I had been avoiding is cutting the flat packs for the backer boxes, especially since I do not have a good tool for cutting 4 by 8 sheets. I have a Harbor Freight circular saw that I tried once and the results were nasty.
This past weekend the eureka moment came, and I had the flat packs for eight backer boxes cut in 20 minutes. This is how I did it. A note that this story contains elements of fiction, and the whole process took longer if you count the Home Depot trip.
Here are the dimensions of the boxes I had in mind. The space between my joists for the backer box with remodel can is quite tight.
The tools I had at hand were my table saw and 10" sliding miter saw. The hurdle was how to cut a large sheet up into reasonably precise pieces. I really should invest in the track saw that Tedd recommended.
The piece to the puzzle came when I remembered that Home Depot will cut a sheet for you (SMH!). However the minimum cut they will make is 12 inches, and you are at the mercy of the attendant cutting them for you, so accurate cuts are by no means guaranteed. So I came up with a plan. I got them to cut two 3/4 4x8 sheets into 12 inch strips and took those home.
The 20 minute action begins:
These are the pieces that I needed to make.
I adjusted my table saw to 11 inches and trimmed down two of the 12" strips. I then adjusted my table saw to 5.75 inches and trimmed each of the rest of the 12" strips into two 5.75 inch strips.
On the miter saw I improvised an extension with marker for the 16.5 inch point. Using it I cut the two 11 inch strips, and most of the 5.75 inch strips into 16.5 inch pieces. I then adjusted the mark on the miter saw to 9.5 inches and cut the remaining 5.75 strips.
Like most historical tales, this is not really how it went down. There are plenty of holes in the story
. I then used cheap Harbor Freight clamps to assemble the boxes. The glue drips easily so you can see how I applied it to keep it from running down before assembly. It is also wise to keep the strips perfectly flat while chopping them on the miter saw otherise the cut edges might be at a slight angle and the box will go askew if you clamp at the ends. Now you know why I am using just one clamp under light pressure in the middle. Titebond is the only wood glue I've used that keeps well in its container for a long time. The maximum cut the 10 inch sliding miter saw can make is probably 12 inches. To speed the process I cut two strips at a time on the miter saw for the smaller pieces. There are certainly much better ways to make boxes. I thought I'd share what I did with my limited resources.