Gun Recommendations for Spraying Shellac

Advice on gun and tip choices for use with shellac. December 6, 2011

Question
I am bidding on stripping and refinishing two full bedroom suites that a client would like redone in shellac. I have sprayed lots of shellac in the past, usually drawer interiors, small boxes, or as a sealer on larger products using my Wagner turbine/Capspray system. I have not sprayed shellac as the final coat on large areas, like a queen sized headboard. I am thinking about using my Kremlin AAA with an 06-094 tip but am concerned it may pump out too much fluid and I'll be getting rid of runs and sags instead of making money. I have a couple of HVLP guns which I use for small areas like chair frames, etc. Does anyone have any experiences or recommendations they'd care to share?

Forum Responses
(Finishing Forum)
From contributor G:
Use a smaller tip.



From contributor S:
I am assuming the client has insisted on Shellac for some reason. Wouldn't be my first choice for something like this but if that is what they want. I would get a sheet of 1/4" plywood and practice spraying beforehand and work out any bugs with your setup. Spraying shellac flows out nicely if applied with a good brush. Just make sure to setup good ventilation and follow all necessary precautions.


From contributor M:
You definitely want to spray shellac with fairly light coats. The tip you'd use is dependent on the how heavy (or light) of a shellac cut you use to spray. Do you know what you would be spraying yet? And do you have a viscosity cup to measure it? I've never had good luck brushing shellac on any surface larger than a drawer bottom. It flows out well enough, but still dries quickly and leaves overlap marks. You could pad it on, although that's a pretty large surface.

Personally, I spray a 1.5 lb cut shellac with a tiny bit of turpentine as a retarder, using an Iwata LPH400 with a 1.2mm needle/nozzle setup. It can be used with a 5 cfm compressor. Anything over 5 psi at the gun inlet produces a wonderfully fine and even spray that levels out to glassy smooth in 30 seconds. Dry to the touch in five minutes and ready for a recoat in ten. You should be able to get good results with a less expensive gun, as long as you have something like a 1.0 mm N/N setup (for a full-size gun, 0.8mm in a mini gun) and the gun is working well - check your spray pattern. The Iwata is kind of pricey if you are considering it for just one project, though. I use it for my main gun, and it is definitely worth the investment. It sprays waterborne finishes extremely well with a 1.4mm n/n setup.




From the original questioner:
The client specified shellac as she wants to retain the authenticity of the piece. I spray a 1.5lb cut and mix my own from flakes. The HVLP guns I have are Iawata knock offs with a 1mm n/n, so I'll give one a try if I get the job.