I have had less time in the evenings to devote to making sawdust out of MDF, but my center channel speaker is about at the point where I can put the drivers in and see how it sounds. I expected to be done by now, but I am getting closer.
I started with 4 MDF shelves I purchased from Home Depot. They were 12 1/4 inches wide, 49 inches long and 3/4 inches thick. I used the factory edges wherever possible to get square corners for my speaker. Per square foot, it was a few dollars more than buying a full sheet of MDF, but I do not have a table saw to make accurate cuts, so I took advantage of the factory cut on the shelves edges to be square and true. Besides, it was much easier to get them into the back seat of my car.
I used a circular saw to cut within 1/4 inch of the true dimension, then I clamped a straight edge to it and used a flush trim bit (the type with the little ball bearing on the end) in my router to get a clean edge (of the right size)
It is not the same as having a complete workshop full of woodworking tools, table saws, jointers, planers, etc., but the trim bit in the router worked very well for me. I was able to get accurate square edges and 90 degree angles using this technique and construction therefore was pretty easy.
The box was assembled with fine-thread drywall screws first, then disassembled for the final re-assembly with glue. I predrilled all screw holes and countersunk all the screwheads. (before I am done, I'll finish the cabinets with veneer)
The most recent step was to glue on the front and rear second layer of MDF. This gives me a panel thickness of 1 1/2 inches in the front and rear. Once they were glued on, I again used my router with the trim bit to accurately trim them to the size of the inner front and rear panels. (I had cut them oversize and did the final trimming after gluing them in place) A bit of sanding and everything is looking really fine.
You can find the plans here :Audax Home Theater Speaker Plans
I'm just about done making sawdust out of MDF for the center channel. I can't wait to hear it in action.
Home Depot shelves - sawdust + Audax drivers and crossovers = DIY Center channel speaker. (basic speaker building math)
Edited to fix link