The paint on the cabinet is just an oil-based primer and I will be painting some kind of topcoat over it. I keep thinking of using an automotive sealer and then topcoat. I am still torn on the color to paint the cabinet though. Right now I am thinking of construction equipment orange or a semi gloss gray. The inside of the cabinet will remain white so as to reflect as much light to the parts inside. Most cabinets are dark inside and seem very hard to see anything.
Next is the hopper. I am using 22-gauge mild steel and it cuts and bends really easy! Some necessary tools are a sheet metal shear, brake and tin snips. I got a 40" sheet metal brake/roller/shear from Harbor Freight and it only cost me $299!
I cut out the bottom of the hopper and made a hole that I can put PVC cap in. I then used my sheet metal brake to bend up the sides and welded them solid.