using mica powders on glass

[Catharine C. Kennedy]

several questions, if you please:
is size put on then powders applied?
or
is size mixed with the powders, then applied?
or do you use one-shot clear as the vehicle?

How do you gild over the back of the mica? Oil or water size????
Thanks!

[Patrick Mackle]

I had a great experience trying mica powders on glass. I used gold size, then sparingly applied the mica colors with my brush and also the foam rubber applicators packaged with the powders (Ron, Letterhead Supplies).
Then I again used gold size over the mica, then applied my gold leaf. It would not make sense to water gild over the mica, as you would not get a perfect mirror-like bright gild, in fact it would probably repeal the water size. I would say continue with gold size over the mica.
It might be fun to water gild the leaf first, then scratch shade though it, then do gold size and then mica powders. I with think that would appear as mat toned mica colored shading on the bright gold.
Pat

[erik winkler]

Photo's Pat.
Show us yours

[Patrick Mackle]

Hi Erik,
I'm very bad at not taking pictures as well as not carrying business cards,,, it's a problem I have.
However this post got me to thinkin' and I dug up my box of mica colors to try out some experimental ideas that run in the back of my mind whilst I'm doing sand blasting.
It's my "theatre of the mind", complete with acid fumes, popcorn, and black "Jujubes" stuck on the floor. (nobody eats the black ones)
If things look good, I will take pictures.
Pat

[Catharine C. Kennedy]

Sweet! (but not the black ones!)

[BruceJackson]

Hi Catherine,

In my experience, you can work using either of the methods you proposed.

If you mix powders into size and brush it, you tend to see the direction of the brush stroke, which may or may not be suitable.
stippling powder onto tacky size gives a nice satiny effect. Just be aware that it goes everywhere, so you have to be prepared for the mess.

It is rarely opaque, so whatever color you put under it will influence the appearance.

One technique I like a lot is to apply mica powder as a very thin layer prior to doing some other finish underneath it. Mix some gold size and turpentine, ratio of 50/50 or maybe 70/30. It's not critical, just make it wet and flowing easily. Put a little bit of powder into it and spread it around on the glass. Daub or and work it with a plastic bag, a sponge or your fingers.

You can also blow some more powder on. Pick it up on the end of a small brush and just blow it onto the surface. You can also flick some more turps, or white spirit onto it so that it opens up and flows, giving all those nice patterns.

I sometimes work with two or three different mica colours into this layer. Mixing them on the glass so that they blend nicely. Leave some areas clear, some areas by one color and other sections blended, as you would if doing marbling.

Once you put the background down, it shows as a lovely shimmering effect on top. It works particularly well with the pearlescent mica powders.

[Patrick Mackle]

Bruce, That is a nice sample, able to change it's look with the direction of the light. It appears to have real depth as well.
Your example is well accounted and well photographed.
Pat

[erik winkler]

The results looks stunning.
Bruce thanks for sharing the mentioned techniques.

Question:
You back it up with 12 Krt, do you ever chemicaly silver over big panels that are priorly treated with painting or application techniques?

Erik

[BruceJackson]

Thanks Pat and Erik,

Erik, I don't do any chemical silvering. Simply because I haven't gotten around to leaning it properly or getting set up with the bath/wet area/chemicals/ etc.
There is a company not far away that specializes in mirrors, they do hand-bevelling and silvering, so I just take it to them if I want chemical work. (it can stink up their place instead of mine...hahaha)

I would be wary of getting chemical silvering behind these types of thin glazes. The ammonia and hot water is pretty harsh and tends to eat the oil-based paints like gold size.

Any time I get silvering, I back up the decorative work with asphaltum, or I do the design work using epoxy inks. That way is survives. But of course, that's not going to be useful to get this type of effect.

Using the angel gilding kits seems to be a bit more gentle, but I don't have hand-on experience with it, so I don't know it's limits.

There's another example of this mica powder glaze technique on my website at http://www.goldreverre.com/finishes.php....go to the two bottom left thumbnail in the left panel.

[Catharine C. Kennedy]

Gorgeous work, Bruce- talk about inspirations!!!!