Chassis Selection

Without doubt, there will be several aspects of this project that are going to be trial-and-error. That is the nature of DIY projects. However, I am trying to minimize the money-wasting aspects. One way I have found that helps is to build the project in your mind and on paper several times before you ever purchase or cut the first piece of material. 

This tactic is going to be invaluable during the creation of this amp, especially regarding the chassis design and cabinet construction. 

My previous sketches called for a chassis made from a 12"x8"x2" steel project box. I have since located a supplier for many more sizes and materials. My latest sketches include an aluminum box (also made by Hammond Manufacturing, the same company that makes the other steel boxes) that measures 17"x4"x3". After some sketching and figuring, this shape is much more conducive to this particular project. Also, aluminum doesn't rust, and comes uncoated/unpainted, which would prevent me from having to sand off the paint from the steel box at all points where an electrical ground would be attached. 

After doing some web-based research, I've discovered there is quite a debate over using aluminum vs. steel boxes for amp chassis. I sifted through post after post and finally concluded that either one should be sufficient, as long as I brace the section where the heavy power transformer and output transformers are to be attached with a stronger, thicker metal of some kind (which I'd already planned to do). The good news is that this new aluminum choice is roughly the same price, maybe a little cheaper than the steel counterpart. 

I'm working on drawing up some plans for the entire contraption, cabinet and all. I will post those pics as they are done.