So I had pretty good luck spraying TiO2 on the tile.
First attempt spraying, 3 medium/light coats with 10 minutes dry time between. 5 parts H2O, 1 part TiO2.
These were run on a 80w red&black at 8.2% power, 44 mm/sec on the left, 50 mm/sec on right.
This is the darkest I’ve ever obtained on tile. Better than any of my spray paint attempts.
The small lettering is very nice and dark but the larger areas get blotchy. This is where I wondered if some flux like borax would help a little.
And in all fairness the blotchiness looks way worse in these photos than in person. But certainly there’s plenty of room for improvement.
Anyway this is a promising start and I’ll probably go further down this rabbit hole.
4" tiles…
