Back to the OP requirements and our collective pragmatic experience, what would we suggest as regards these motors for 'cutting balsa wood up to 1/4" thick"?

It would seem he has a few of these available (work parts bin?), but obviously traverse speed and depth of cut is going to be severely limited even with a fast spindle and a single flute cutter.

The likely use is repetitive cutting of wing rib parts (I know that was the bit I never managed to get right often enough) but is the OP on a hiding to nothing or should he at least give it a try.

Constructive views?

Personally I'd give it a go as a learning exercise, but not be too dissappointed that I'd need to upgrade to bigger (NEMA23) motors pretty much straight away.

Chaz, can you tell us more about the rest of your router design?