This past weekend I finally had the time to start physically building the cabinet for my 90g tank. After a $700 Saturday morning trip to Home Depot to buy a new jig saw, circular saw, cordless drill (all DeWalt), 2" exterior wood screws, four 4x8 sheets of 3/4" oak plywood, and misc trim pieces....I started the build.
First step was to test my new Perfecto tank for leaks. Thankfully this was uneventful.
I opted not to use a table saw for this project, since cutting 4x8 sheets of thick plywood on a table saw is very difficult, and to be accurate requires two people. Instead, I bought a $13 sheet of 3/4" MDF fiberboard, and used this as a cutting board. I layed it directly on the concrete floor of my garage, no saw horses. This way I can position myself anywhere I want while making cuts. I then made a 4' long and 8' long rotary saw jigs to make perfectly straight cuts with a handheld rotary saw. In the end, this process was MUCH easier and MUCH faster than fumbling with a table saw.
The 2x6 header screwed to the front panel of the cabinet. The 2x6 carries the weight of the tank, not the plywood. This allows the opening in the front panel to be unobstructed. I bought a $100 DeWalt jigsaw to cut out the opening in the front panel....but this resulted in a very sloppy cut, as the flexible blade of the jigsaw didn't leave a perfect 90° cut the way a rotary saw does. Also, the jigsaw refused to follow my jig; the blade would start to bend and the saw would then follow the blade. I ended up simlpy following the cut line with my eye, trying to be as accurate as possible. If I could do it over, I would use a rotary saw and plunge-cut into the panel, getting as close to the corners as possible. Then I would only use the jigsaw to finish off the corners.
These 2x4s carry the load of the tank directly to the floor.