He'll be hard pressed to build a tilt mechanism that's better than that found on the Grizzly machine I mentioned.

Check out that item on the Grizzly site. Both tables tilt and LOCK firmly in place at any angle.

That Grizzly, with a 60 gr belt is a "metal eatin beast".

Also has a pretty good dust collection system built in.

A good belt sander can be great for tweaking a 45 deg angle on a frame. Ever tried taking off 1/16" with a bandsaw/chop saw/dry cut saw? Easy on a belt sander properly set up with a mitre gauge. Need a 46deg angle? No problem.