WarmGlass.com

Hello. I am an apprentice neon bender who has been experimenting with other types of glasswork.

I'm trying to use freeze-and-fuse to make little dinosaur skulls from silicone molds I made myself. The ice cubes came out fine, but when I fired them according to this cycle (http://fusedglass.org/downloads/schedul ... hedule.pdf) they came out all slumped over on each other. These are made from System 96 recycled frit.

Is it the cycle I used? I didn't leave the ice cubes out to 'melt' either - some tutorials say that's important, others don't seem to stress it as very important. Some advice on both would be greatly appreciated.

I haven't done a lot of freeze-and-fuse but as far as I know, you're supposed to be using powder. You mention using recycled frit; is it ground to powder consistency?

It's pretty thin and seemed to take a good mold when I demolded it. (Sadly, did not take pictures of the ice cubes.) There was some crumbling when I demolded, but it wasn't the dramatic splattering/collapsing of the final product.

Here's a picture of the leftover frit I pounded down.

I've done a lot of FnF and if you use anything other than powder for small things, you are going to have problems most of the time. The power packs down very tight together and doesn't pull apart when it shrinks down during firing where the fine and bigger do not pack in tight. You can get away with using fine with powder in larger pieces. I've done this with several large object (over 1 pound of frit in size) by using fine in the middle with the power surrounding it. I didn't mix the two, but placed it dry on top of a layer of powder then I put powder on top of the fine and wet it all down.

I do it both ways after I pop them from the molds. I'll fuse them right away and sometimes I've left them over night sitting on the tray. They are fine as long as you don't touch them. If they are thawed and you touch them, they collapse into a file of powder (looks really neat too). You don't want to leave them in the freezer any longer than necessary though or they dry out and have problems coming out of the molds. I also use a lot of ice cube trays.






Mike

Interesting and depressing at the same time, because I don't have any powder frit on me.

But it's good to know what the cause was, and that it wasn't the firing cycle. I don't know nearly enough about the science and theory to even begin to figure them out on my own.

If you buy yourself an old electric coffee grinder you can crush what you have into powder in small batches. Just make sure you use a face mask when opening the lid and pouring out the powder. You could try looking in places like Salvation Army, Value Village depending on where you live, Walmart sells new ones fairly cheap. Or ebay places like that. Hope this helps.

Thanks guys. You were right, it was the frit size. This new batch came out awesome.

Great; now go bury them in remote areas!

My question is a little different. I am trying freeze and fuse, but my problem is is getting it out of the mold. It won't pop out and crumbles. I am wondering if the water is the problem. We have a water softner. Has anyone had a problem like this?

To me it sounds like you are not using enough water if they are crumbling straight away and that maybe you are not freezing them for long enough. You could also try rubbing some Vaseline or some type of release agent on the molds first.

What kind of mold are you using? Is it plastic, rubber (or one of the rubber type materials), is the opening small? I've had some molds that gave me trouble. The rubber ones that you have to flex and spread to pop out the object can be difficult for things like FnF because they are meant to be used with a mold material that is hard when it's cured, like plaster. I have a couple of molds I'd love to use but I've not tried them for this reason as I figure my FnF object won't survive the extraction and I don't want to destroy the mold for one FnF. Some of the rubber molds I've been able to cut slits at the opening to create a bigger and more flexible opening but mostly I stick to molds that have openings the same size or bigger than the FnF object I need to extract.

The water may be causing problems, since softener is usually salt based and salt water doesn't freeze very well. Even though we have good water, I don't use tap water. I use bottled water and some people use distilled water. I find just plain ole cheap bottled water from Costco works just fine. So you might try that next time. Also, are you putting a very small drop of dish soap in the water? I use Photo Flo (since I have a lot of it from my darkroom days) but a small drop of dish soap is what others use.

Mike

Jet Dry

I thought the first time that maybe I didn't have enough water. I left more water the second time and still had the same problem. I am using plastic molds and some of them are really shallow, some are fairly deep. That didn't seem to matter, they all had the same problem. I will try again and use bottled water and some jet dry. I had done some fnf before and had no problem. We got a new water softner and it uses a different kind of salt. I think the water must be the real problem, but I am willing to try anything. Thanks for all the suggestions.

You can have to much water. From the way I understand how this works is that the water is used to suspend the frit particles so that you can get them in the mold and then they sink and snuggled together (notice how the frit left at the bottom of your cup of water is much harder than dry frit in the jar?). As you remove the water by blotting it, it causes the frit particles to snuggle closer... kind of like vacuum packing, as you take the air out. If you leave to much water in, some of the particles are still going to be suspended a bit (all of this is on a very micro level) or at least not packed down good and tight. It will freeze but not be one solid mass. So it isn't as strong as it should be and it will come apart. When it's frozen as a solid mass of frit particles that are locked in together, the object can be very tough. I've had them drop out of my mold from several feet up and not come apart. Other times I've found them coming apart before I've flexed the mold very much to pop them out. You want to get all of the shine off the top before you freeze them. When the shine is gone you have gotten out about as much water as you can.

Mike

I always tap the mold to remove excess water and bubbles and blot with a paper towel until the frit feels firm in the mold. I only use distilled or boiled water otherwise i get devit and I do have a water softener. I usually freeze mine overnight to make sure they are competely frozen.

I also use an old electric tooth brush held onto the side of the mold.
This vibrates the powder and gets all of the excess water out.
The other Jim

I too use a vibrating toothbrush to expelled air bubbles out of the bottom of the mold, makes for a nice tight fit.