I have used the finish you mentioned before, and altough it does work, and nice and clear, there are issues with it. It can breakdown over time also. I had a cue that I did, and altough it took a while to finish, it looked almost just like auto clear, but after about a 8 months to a year, I began to see tiny bubbles under the surface appearing in one area that were not there before. Could have been something i did in prep, but would have thought it would have shown up sooner. I believe there are better waterborns out there that may be more suited, but some are kind of expensive, and I have not tried them yet. Bonding can be an issue also. (Thanks for that tip Mike, did not know about the bonding agent you mentioned)
The aluminum does put out a black color that is a pain in the rear and can stain pretty badly. as far as polishing though, I have a roll of micro-mesh just for aluminum, and it works very well before buffing, altough I have not used aluminum in the joints either, but use it for other stuff. I aggree if using aluminum in a joint, that taking care of it first, when possible, would be a better idea then after installation.
There are several type finishes that could be used without the spray equipment, but how well they bond,dry, buff, and polish are the keys. Also durability 7 clarity are concerns.
Hand rubbed type finishes can be used sometimes, they are quick & fairly easy to do, but don't look the same as a thick clear, so depends on the woods and design of the cue as to how good they look. Some designs built mostly from wood parts I actually like better with that type finish, but only certain ones. I did a cocc-birdseye cue like that, and was pleased with the look & feel on that paticular cue, but not for My other designs. since the coco is oily anyway, it made things easier, and brought out a deeper color. The cue was kind of a sneakie pete design anyway, but had floating points as oppossed to a fullsplice, so it was a decent donor for that type finish.
just to add that Sealing the cue well before finishing, can save alot of hassle with some types of finish. I've found that out the hard way. Not all finishes make a good sealer.
I have been experiementing with different finishes for a while trying to find something quick, and good, that I don't have to use My spray gun with, but they have all had there own issues to work around. I'm trying something different right now with alittle trick i picked up added in the mix, but don't know how it's going to come out yet, because it's not really quick, and still in the proccess. If it comes out decent I'll pass it on.
I use to paint custom homes, and there were some waterborns that sher.williams had out that seemed pretty good, but have not tried any on cues. might be worth checking into. I know i preferred their other paints over many others brands, so who knows what kind of waterborns they have out now.
There is also a place online that's supposed to have good waterborns, I have heard it mentioned that they work well on cues, but have not tried them myself.
Good luck, Greg