I’ve looked on this forum for info on this topic but came up short.
I love working on glass with 10Watt Diode laser. I’m experimenting with different settings and so forth.
But, I’m having a real problem getting black tempera paint evenly on the glass. I’ve tried foam brush…smears and leaves streaks. I’ve tried letting the first coat dry before trying to fill in the streaks, but that doesn’t work either…removes the first coat.
I’ve tried spray bottle with 50/50 water/paint mixture, also 50/50 alcohol/pint mixture. I can’t find a mixture that will spray anything but globs.
I would appreciate any suggestions you folks may have.
I use a spray on “cold galvanizing” paint from Rust-Oleum. One pass with a 10w diode leaves a black marking. Multiple passes leave a white engraved mark.
if flat , clean glass with isopalyne apply 2 coats of dishwashing liquid ,let it dry between coats
get some black acm panel, lay glass on it and engrave away , once finished wash glass with warm water finished, have used gloss black aerosal on metal and engraved and worked ,
if curved could try dishwashing liquid than couple coats of black aerosol emanal might work
I found using an EXPO Dry Erase Bold Black marker does a superb job. Minor streaks does not seem to make a difference. Water and Mr. Clean Magic Eraser makes cleanup fast and easy.
I have heard cold galv is the go on curved surface, yet to try it as no rotary and to lazy to spray on flat glass when i can lay it on black acm, hmmm just had thought , wonder how it would work on a galvanised sheet if same chemical reaction would ocurr.
Larry, I finely got my tempera to coat the way I thought it should. I ended up mixing 90% water and only 10% paint. Then I bought a misting bottle, like granny uses when she is misting her potted plants. I had to give the glass 10 to 15 coatings and had to let each coating dry before spraying again. After reading what Mike said about dry erase I’m going to get me some. And it should be 10 times faster than spraying tempera. Good luck.
Randy
ChalkWatts ChalkWatts - YouTube has a terrific youtube video on this very topic. He found that the key is using a specific brand of tempera paint. PRANG tempera paint. I bought a gallon online from Walmart at a great price. I cut it 50/50 with distilled water (tap water can grow things over time). I use a simple bristle brush about an inch wide (trim brush). I keep a spray bottle with 95% isopropyl alcohol (I like using those little spray bottles for eyeglass cleaner) and clean the glass first with the alcohol. I found that if I didn’t, it would bead up in random spots. Now, after cleaning, I just brush it on in one direction then another until it looks even (it’s pretty quick), then just let it dry. Works flawlessly! After it’s done, we’re off to the sink where it washes off incredibly easily.
I played around with etching glass using tempera to get a frosted result and also my TiO2 / Tempera / Water mixture to get a black result and then used both methods in sequence to create one design with both frosted and black. I used the small square anchored on the honeycomb to make sure I could get perfect repeat indexing.
I use this HVLP spray gun from Harbor Freight to apply the coatings and it works really good: 4OZ DETAIL SPRAY GUN W/RE SKU 61473.
All washes off with warm water. I also use the sprayer to coat ceramic tiles with the TiO2 mixture as well. You definitely get a perfect even coat with no streaks on glass, ceramic metal or what have you.
,sounds a daunting task
