i have tried rattle cans. As someone said above little and often with light sanding between coats is essential. 
I love making guitars and now have a pile that need finishing. I avoid finishing as a) I’m not good at it and b) it takes weeks with spray cans etc. 

I look forward to someone coming up with an easy, quick and inexpensive method so that I can finish some of the backlog in my shed!

jim

@jamesalexandermcmillan

I've finished solid wood with a drying oil only and no lacquer or varnish. It's very forgiving as it doesn't crack or chip if knocked and any minor dents can just be rubbed down and oiled again. 

With rattle cans I always fill the sink with warm water and soak the can for a while before using. Helps to give a better pressure and get the paint up to a decent temperature.

 This body in Bubinga was finished with oil although the maple neck was sprayed. Also seen acoustics with only a rubbed wax finish.

Cheers. Never tried heating the paint first. Sounds like a good tip. I’ll try with the next one (a yellow bass with a musician pickup). 
paint always runs somewhere normally with anything but a very light coat resulting in sanding almost every time somewhere. 
ta Jim. 

@jamesalexandermcmillan

If you are getting excessive paint runs it's likely that the paint in the can hasn't mixed properly and there's too much solvent, not enough solids. A clue is if the propellant runs out and there is still paint in the can. Gentle heating should resolve this but obviously no direct flame or boiling. I thought of this when touching up rusty spots on my motorbike in the cold weather. Also heating metal parts with a light flame.

I think I'm correct in saying that nitro cellulose doesn't need sanding between coats as it bonds to itself - unless there are runs. These I let dry and remove as much as possible with a sharp blade.

Perhaps Mark has covered this on the finishing course. Haven't kicked that sleeping dog for a while so why not give it a poke. 

@jonhodgson

I tried the acrylic sealer and top coat first but found it peeled off too easily, then moved to cellulose. I still have some of that left in the tin which I use for non instrument wood projects as its well past the sell by date. Mostly for sealing the wood on my sanding blocks as the double sided tape comes off more easily.

I also tried an acrylic brand called Standox but found this wasn't very good either, peeled off and chipped with only a slight knock.  

If you can get Chesnut spray thinners instead of brush thinners it will help to get a better gloss finish.