Stained Glass Paint Queries
Stained Glass Painting Answers
Kiln Firing Program For Stained Glass
Green Man Painting
I just bought a new glass kiln. All of the pre-programmed firing schedules are for fused or slumped glass and seem very slow. What is a good kiln firing schedule for standard matte (Reusche) painting. I want to fire it to 1250F/675C degrees. And do you need a hold/soak time? I don’t remember using one.
If you’re just firing paint you can go up far quicker than if you’re fusing or slumping glass.
You can go as fast as 930F/500C degrees per hour, but you have to be careful about thermal shock. I would personally not fire quicker than 570F/300C degrees per hour, but I’m never in that much of a hurry!
For Reusche paint I fire at 1200F/650C, soak for just 5 minutes and then OFF. If I fired to 1250F/675C I wouldn’t soak it at top temperature. I do anneal larger pieces of painted glass.
Printing With Heraeus Paint
Colorful glass samples
I recently learnt how to print onto glass using Heraeus paint in powder form which I then mix with a medium. I capped the tile with 3mm Tekta and after firing it resulted in lots of little bubbles which created a lumpy look to the surface of the tile which I do not like at all. Any suggestions on how to avoid these bubbles? My tile was 20 by 20cm
I read somewhere on your site that you pre-fire enamels before capping. Do you think I should do the same with the enamels I use for printing?
Also when you fire many layers to get better colour density, what temp do you fire each layer at? Robyn
Thanks for your questions Robyn. I’ll try and answer them all!
I would pre-fire enamels I was going on to fuse, yes. The same applies whether or not the enamels are printed or painted on. Depending on the enamel, you can fire low firing enamels from 1020F/550C to 1255F/680C top temperature. You can soak from 5-20mins depending on your kiln. For Heraeus low-firing transparent enamels I would fire at 1200F/650C degrees and soak for 5mins.
The bubbles could be occuring because the medium doesn’t have a chance to carbonise if you don’t pre-fire, and/or because you’re putting the textured side of the Tekta facing downwards, allowing pockets of air to trap during the fusing process = bubbles.
I fire Heraeus at 1020F/550C and soak for 10mins if I know I’m going to fire another layer of colour on top. For the final firing I go up to 1200F/650C degrees and soak for 5mins, to make sure that they go nice and shiny.
Hope that helps.
How To Paint Glass – Matting
Yellow glass with swirls
shade and matting? problem with reproduction of soft matting, see photos. is there a special paint mix!! My matting seems to be rougher or bolder, I am looking for a soft fine matting and stippling. by Karl Young
I’m hoping that you mean that you’re trying to replicate the matting above, and not that you’ve done the matting above and it’s not good enough!
For starters, the paint in your photos is brown, which gives softer look than the black paint for glass. Bistre brown Reusche paint is great for this sort of painting job.
You will definitely have to use a badger brush, the bigger the better. Nothing else will do I’m afraid.
Good luck and I hope you enjoy this process – it can be quite addictive.
Kiln Vent Use When Firing Paints
Kiln with vents
I just bought a glass kiln. Basically all I want to do with it is the painting. I heard that I should use the vents if you’re using lead paints. Is that true and if it is how do you vent the kiln?
This is an important question. When you open your kiln vent you do two things; you give the poisonous fumes a chance to disperse, and you prevent these fumes from causing devitrification (when crystals form on the surface of the glass in an unpleasant ‘cloudy’ fashion).
So when is the right time to use the vent when firing paint? From room temperature up until about 750F/400C degrees. It’s not crucial, but you don’t want to leave the kiln vent open throughout the whole firing cycle because the kiln will cool down too quickly and not give your glass a chance to anneal properly.
It’s best not to be near the kiln during the firing programme, as unpleasant fumes do escape, even if the vents are closed.
Hope that helps, and happy painting!
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