C Newlin Posted January 21, 2019 Report Share Posted January 21, 2019 Hi ho friends! I'm beginning to explore airbrushing underglazes onto my pieces and while I'm very familiar with underglazes, I'm fairly new to airbrushing. I'm well aware of the safety considerations regarding spraying ceramic materials - I have a mask and a nifty little homemade spray booth, so I'm good there. I'm primarily using the airbrush to blend, so I apply the base colors first, then go back with the airbrush to soften lines. I'm using Amaco Velvets, thinned and put through an 80 mesh screen. Using an inexpensive airbrush from Harbor Freight double action brush that uses a little jar (as opposed to gravity feed). It also has a cup, but I've not used that. Not sure how much to thin or sieve my underglazes, or if there is another airbrush set-up I should use. The biggest issues seem to be keeping the particles suspended and not having a smooth, continuous stream of underglaze. Plain old water goes through just fine. Thanks for any tips/thoughts! Link to comment Share on other sites More sharing options...
neilestrick Posted January 21, 2019 Report Share Posted January 21, 2019 Is the brush clogging due to particle size or form the viscosity of the underglaze? If it's particles size, you could sieve through a 120 or 150 mesh and see if that works better. Pay attention to how much material doesn't go through the screen. It shouldn't be much at all, but if it is, it could change the way the underglaze melts/fuses, or the saturation of the color. Velvets are pretty darn smooth, though, so I don't expect there to be much that you can't work through the screen. As for how much to water them down, I don't have a specific number, but as little as possible. As you add more water, they're more likely to settle out, as you're seeing. You may also want to try different size tips on your airbrush and see if that helps. Link to comment Share on other sites More sharing options...
Min Posted January 21, 2019 Report Share Posted January 21, 2019 What psi are you running at? Link to comment Share on other sites More sharing options...
C Newlin Posted January 21, 2019 Author Report Share Posted January 21, 2019 6 minutes ago, Min said: What psi are you running at? Hi Min, It looks like it's set at 55. I had thought it might be working hard to keep pressure up. It's one of those $80 Harbor Freight specials - all I can afford at the moment. 2 hours ago, neilestrick said: Is the brush clogging due to particle size or form the viscosity of the underglaze? If it's particles size, you could sieve through a 120 or 150 mesh and see if that works better. Pay attention to how much material doesn't go through the screen. It shouldn't be much at all, but if it is, it could change the way the underglaze melts/fuses, or the saturation of the color. Velvets are pretty darn smooth, though, so I don't expect there to be much that you can't work through the screen. As for how much to water them down, I don't have a specific number, but as little as possible. As you add more water, they're more likely to settle out, as you're seeing. You may also want to try different size tips on your airbrush and see if that helps. Hey Neil, I don't think it's clogging, as I can switch to a jar of water and get a nice spray right off the bat without cleaning it. I am suspecting I may be thinning too much, as I am getting a lot of settling out of the pigments. May I don't need to thin as much as I have been. You both have given me some things to troubleshoot. Thanks. I'll play around and report back! Link to comment Share on other sites More sharing options...
neilestrick Posted January 21, 2019 Report Share Posted January 21, 2019 If it's not clogging, you may need more pressure to pull it through. If you've got a small compressor, it may not be able to keep up. Link to comment Share on other sites More sharing options...
Min Posted January 21, 2019 Report Share Posted January 21, 2019 I haven't used an airbrush from HF but I've got a few of their sprayguns, I remove the filter from the guns because they were forever clogging up and driving me crazy, might try that. (removing the filter not going crazy) There should be an adjustment dial on the gun itself, try playing with that to increase or decrease airflow. Link to comment Share on other sites More sharing options...
Bill Kielb Posted January 22, 2019 Report Share Posted January 22, 2019 I spray underglaze often and tip size is important. Also siphon pickup brushes are at a big disadvantage since you would like to spray as dense as your airbrush will allow but overcoming gravity with a really small volume of air is often difficult. Pick the largest tip size you are comfortable spraying and siphon feed is difficult but doable. just my observations spraying. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.