Homebrew PCBs

I ran an epilog 100 watt machine in the late 90's, basically had it 
dropped in my lap at my job. During initial testing I even engraved 1/8" 
lettering into a fig newton. This is exactly the sort of project I'd have 
been given then.

     The answers to your question may be approaching this from the wrong 
direction.

> Question is: What could easily be used to coat a copper clad board that
> will be resistant to the etchant (pick your flavor).

     I didn't send anything to be etched, but guys (& gals?), just take 
the question straight:

     What's the easiest etching resist to apply?

     It doesn't have to be a photo-resist, just something that will live 
through the etching process - an etch-block. Laquer? Auto primer? Asphalt?

     Once John applies it, then he can see what power and speed is 
required to reliably remove it. Even if it's a spray-on that tends to 
run, as long as it's not fused glass the laser should be able to remove 
it. He just seems to be looking for the easiest one to apply to the board.

>There also seems to be a widespread want of something better, but I
>haven't seen any solutions yet (still digging).

     Something better/easier than spraying or brushing it on? Of course 
there's dipping, but that's no better. Some sort of tape maybe? Is there 
a tape that will survive a trip through an etching bath? Of course, then 
there's the difference between cleanly ashing the tape (raster cut...) 
and having to edge cut it all and hand-strip it. If any remaining 
particles are small enough the etchant will undercut them, so there's a 
point where they'll be negligible.

     yeah, my kinda problem... Oh, and feeding the machine CorelDraw 
files worked much better than AutoCad files, I finally ended up just 
redrawing everything in CorelDraw (true single lines).