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old_picker
30th September 2020, 12:48 PM
Used shellac a bit in spray guns but not consistently until fairly recently. I'm using shellac as seal coats on small jobs [guitar bodies] and finding it is not flowing well even with the fluid adjuster almost wide open. Tip is 1.5 in a star gravity fed mini. it seems to start off blowing a good amount of finish but by the end of a pass it is struggling to pick up much finish. the shellac consistency is roughly equivalent to milk:

Bigger tip?

More metho in the shellac?

Slave
30th September 2020, 07:56 PM
Do you strain the shellac as you put it into your gun?, doesn’t take much to slow/ stop the flow

old_picker
1st October 2020, 09:52 AM
No I haven't - I have a couple of nice screens 100 and 200 mesh. Unsure how the plastic holding the mesh will hold up to metho wash out. Lacquer thinners makes sticky I found out :[ Used to use stockings which aren't as available round here as much as they used to be -

Slave
2nd October 2020, 08:24 PM
I use stockings most of the time, time a knot and cut off what I need , can get 4/5 pieces out of one leg

PaintMan
10th October 2020, 04:11 PM
Whilst shellac has a lot of uses in DIY furniture/restoration I have not seen it used much for spray application. Some years ago I did use shellac sealers followed by brush applied Cabothane type topcoats. Today I have just been spraying a lot of sealer but rather than Shellac I have been using an industrial precatalised sanding sealer Mirocat PC 3242 which is a lot easier to use. It dries faster than shellac and because it contains some zinc stearate it sands very easy when dry in 10-15min. You can also add spirit dyes to adjust the colour if needed. I also have seen these coatings used very successfully on guitars in both factory and craft production.
For both sanding sealers and topcoats I use HVLP spray guns with a top gravity feed container that in my case work well at low PSI (35-40) using a 1.7 tip. I also fit a small inline strainer (plastic) that comes with these guns and sits in the bottom of the material cup. You can also buy small cone shaped paper filters with plastic mesh built into the bottom section from about 50 cents each from most industrial paint suppliers.

Cheers,
Paintman