Although it may seem complicated, producing cellulosic glue is quite easy - if you can find the nitrocellulose, that is. It is getting as scarce as hens teeth. Older combs, eyeglass frames, etc. were made of that stuff; now it is hard to find. That is the kind of plastic that burns fast and clean, with no smoke and little residue. The best example is ping pong (table tennis) balls. Now that is the only source I can find; and that would make a very white glue, seeing its condition during glue production would be difficult, and it would not (does not) look good on the balsa. I have some older plastic and some ready made glue from older years. I apply it using a disposable syringe, the type with no rubber on the plunger.
To prepare the glue, you just chop the plastic up and put it in a clear glass bottle with pure acetone. On the first few days it is jelly like, but after some shaking, mixing, changing position of the bottle, etc. it starts getting more fluidic. Consistency is adjusted by adding acetone, so it can be made very thin and light. I use no other additive.
The Sherline can be operated manually now in HHC mode (Human Hand Control), but I should start using it as a CNC tool because this model has lots of parts to be cut from FR4 PCB sheet. Most probably the model will not get finished by the end of May and I will be dismissed from the contest
so I might as well try that now - I was reluctant to spend time on that.