Cast Glass, Outdoors?

[Planet Glass]

I want to make a modular cast glass birdbath. I realize this will be a large undertaking.

Before I start out, what are the hazards of keeping large cast glass objects outdoors? Will I have to bring in indoors in the winter?

[bert weiss]

I want to make a modular cast glass birdbath. I realize this will be a large undertaking.

Before I start out, what are the hazards of keeping large cast glass objects outdoors? Will I have to bring in indoors in the winter?

I have a fused and slumped birdbath in my yard. I do bring it in for winter. When water freezes, it expands. If the shape is not drafted enough, this will crack the glass.

Be aware! The first birdbath I made was clear glass, and kind of deep. When it filled with water, the unit became a lens, and the sun burned grass beneath it. This could have started a fire.

I have since learned that birds like shallow water and a not slippery surface.

[Planet Glass]

Wow, I didn't think of that! I knew about shallow water (running water in fact, I want to house an aquarium filter in the foot), but I didn't know about non-slip surface!

Maybe I should cast it in cement...

[bert weiss]

There are many ways to get the surface of glass to not be slippery. The one I just did used frit coated with satin etch as the surface. It is bumpy and not slippery. I made the satin etch with flux designed to gloss at 1380/silver mica/alumina hydrate. I fired it to 1250.

The project was a test using Youghiogheny EZ fuse large frit on 10mm PPG 10mm float glass. I fired the glass so that the frits rounded up, but did not flatten all the way out. Then I sprayed on the etch and slumped on a mold I have.

You could also use sand stuck to the glass, if you like. Slippery glass is pretty, and will make a lovely ornament. It is just not as bird friendly as it could be.

[Dennis Brady]

One of my customers specializes in making fused/slumped birdbaths and sells them to numerous garden centres. She sandblasts the inside to produce a slightly rough texture.

[Planet Glass]

Is there a picture, bert?

[bert weiss]

http://customartglass.com/images/birdbath-yough.jpg
wrought iron tripod by Peter Happny

http://customartglass.com/images/birdbath-yough-detail.jpg
Detail close up

[Planet Glass]

That's very classical, and very zen at the same time!

[bert weiss]

That's very classical, and very zen at the same time!

Thanks

I have lots of glass outdoors in my yard in NH. This past winter, I lost several pieces to snow loads. I have never had this problem before. Of course, pushing 4' of solid ice and packed snow off of the roof and on to the glass wasn't a good recipe for keeping the glass intact.

I have 2, inch thick obelisks that live in the gardens. One has been outdoors for over a decade. Three years ago I smacked the edge and put a crack in it. That crack has not grown at all. The crack itself is at the bottom of the glass, and is regularly buried in ice and snow. On a sunny afternoon in March, there is always direct hot sun shining on the half embedded glass.

[Boris]

Nice piece Bert. Cool idea for the stand.

[bert weiss]

Oh my gosh. Last night there was a heavy rain and it toppled over. The glass must have been situated such that when it filled with water, it got out of balance. Big bummer. I have another one...

I've been making and using these for over a decade, and this is the first mishap I have ever heard of.

I discovered that the tripod wasn't sitting on level ground in the garden. I replaced the bowl with another I have and set it back up in a different spot.

[Planet Glass]

Yikes!

I decided I would make the bird bath out of resin, it certainly will be lighter.

Now I'm making cast glass upside down thistle feeders. I'll still be making the screwcap out of resin though. I'm going to shape it like an umbrella... or a medusa... I'll post pictures in a few days.