Frit/powder Question

[Buttercup]

I’d like to add some last-minute embellishment to a copper-foiled/leaded panel and would appreciate some advice.

Some white flowers in the design really need pale yellow centres as they look as though there is something missing as the rest of the panel is quite detailed with painted and fired inclusions. Since the panel is fully assembled I can’t simply paint centres on the flowers.

I have some Sys 96 yellow grit, possibly some powder, too (I’m not in the studio right now) and was thinking of fusing mini-powder wafers and glueing them on. They would ideally be tack-fused to retain the granular surface of the frit and about 3/8” wide with irregular edges and flat underneath.

Searching the board I’ve found references to powder wafers but don’t know if the recommended schedule would be too hot for such tiny pieces: AFAP to 1285, Hold for 10 min. Off

I don’t want them to pull in and form little balls. Would it be better to make a larger wafer and cut it up with nippers or the ring saw?

If someone can give me some simple 1,2,3 instructions I’d really appreciate it as this is literally last minute. I don’t have time to try to figure it out. Jen

[Don Burt]

Looks like its been a few hours. Whatja end up doing?

1285, hold for 10 and then off sounded pretty reasonable to me.

[Buttercup]

Hi Don. My first atempt was during construction. I tried fusing yellow frit to white glass. Kiln fried meltdown. Without a functioning kiln I pressed on without the yellow centres, which I'm not happy with. My next attempt was to make up flower centres from frit stuck together with Welbond. They peeled off quicksmart. A private message suggested much the same idea using silicone but I'd like the slightly smoothed yet still granular effect of a tack fuse. Uncooked frit stuck on will have sharp edges that will catch any cleaning cloth that comes within a foot of it. Besides, that's taking cheating to a new high. I'll feel bad enough gluing them on.

I tried using a butane torch on a little pile of frit but that was of questionable stickability and unsatisfactory appearance so I'm about to try the 1285 ℉ hold for 10. Thanks for the confirmation. Any thoughts on making up one grainy pancake and cutting it up versus individual little pieces? Will the little pieces try to round up into little 1/4" blobs? I just have fine frit, no powder.

If it works the next question is best adhesive. I hear E 6000 mentioned a lot and it appears I can get it here. I have 2 part epoxy but haven't used it on glass before. Any comments on that? Any and all suggestions appreciated. Thanks, Jen

[Buttercup]

Any suggestions as to how thick I should pile the frit, please? I'm looking for a finished product about 3/8" dia. and just thick enough to have enough integrity to stick together with a smooth, yet still granular surface. Thanks, Jen

[Lori Schinelli]

Hi Jen,
I have another suggestion.
Here in the US the craft supply stores sell a glass paint , both opague and transparent, that heat sets at very low temps. I have successfully used a hairdryer to provide the necessary temp to make the paint permanent. ( One of the times it was done on the front of a farmhouse style sink in my kitchen, so I know it is permanent and will not wash or wear off. Its been there for at least 10 years and gets wet all the time).
Lori

[Morganica]

Grainy pancakes tend to fall apart when you cut them, unless they're very melty. (Or you do what wedding dress makers do with lace, and selectively snip at the thinnest, most tenuous connectors)

More than likely, your fired panel was just too slick for the glue. If you give both pieces some tooth with sandpaper, you'll get better adherence. I have a lot less trouble with adhesives also if I superclean with acetone and denatured alcohol, then apply silane. According to an adhesives engineer I spoke with at 3M, glass is hygroscopic (attracts moisture), which can degrade adhesive bonds. The silane apparently cuts down the hygroscopic tendencies and keeps the moisture from seeping in. (I wasn't aware of this until he told me, I don't have other references for it except that I have no bond failures when I use a silane pre-treatment.)

One other thing you could do is get some lava cloth (that refractory fabric with all the texture) or 1/8 inch fiber paper that you can gouge and rough up a bit. Cut pieces of yellow sheet glass, stick them on the fiber paper and fire. You'll get flower centers with a lot of natural-looking texture on the underside. If the topside has rounded over, run them over some coarse wet-dry sandpaper until they're flat--that's the side that will contact the glass.

Then rough up the flower centers a bit with more sandpaper, clean it really well, apply silane. Glue them on with your adhesive of choice. Not sure what's available over there--I'd use HXTAL to be sure (and if I had a few days to let it cure), or hardware store 2-part epoxy.

[Buttercup]

Lori, thank you for that very practical suggestion and reassurance that such paints will set at a relatively low temperature. It would not be subject to any wear and tear and won't be exposed to weather as it's to be mounted indoors in a light box.

Shortly I’ll be able to open the kiln and see what’s lurking in there. If I don’t like the look of the frit blobs low temp. paint may be the way to go. I hadn’t realised a hair dryer would provide enough heat to set it as any references to it say ‘Use your kitchen oven’. I could get those locally.

If I go that route I could do as Cynthia suggests and rough up the surface a bit so the paint gets better adhesion.

Cynthia, thank you for that information. I’d never heard of silane so looked it up. According to the big encyclopaedia in the sky:

silane, a gas made up of silicon and hydrogen that explodes on contact with air.

Scientific American had this to say:

http://www.scientificamerican.com/artic ... ovoltaics/

Now I don’t feel so smug when I consider the solar panels on the roof.

I did however find a local supplier with large drums of it so will call them during business hours to find out the smallest quantity I can buy, or if I can get a sample. I have denatured alcohol and acetone anyway.

That’s a good idea about firing sheet glass pieces on roughed-up 1/8 fibre. I have that, as well as some very old 2 mil yellow Wasser.

I’ll find out today when the panels will be picked up and see which solution I have time for.

Thank you again, Lori and Cynthia, for the input. Jen

[Babette (Shawn)]

His Glass sells Silane:

A-1100 Amino Silane Pre-Treatment
$22.00
Qty:
Ratio: 560mL per L

Size:
Description
Please note that A-1100 is classified as a Dangerous Good. A-1100 may only be shipped via Ground shipping. We cannot ship this product via air shipment (this includes any shipments to Hawaii or Alaska domestically). If you do require an air shipment of this material, please contact us directly for a Dangerous Good shipping quote.

A-1100 Amino silane is a glass pre-treatment for us with most optical epoxies. The A-1100 helps the epoxy bond to the silica in the glass and creates a longer lasting more reliable bond joint.

After cleaning your glass and before bonding with your epoxy, simply wipe or spray A-1100 onto the surface of both areas to be bonded. Allow to dry or use a hair dryer to dry the A-1100, then bond as normal with your choice of epoxies.

Used in conjunction with throughly cleaning the glass surfaces prior to bonding, A-1100 increases the success rate of most bond joints.

[Buttercup]

Thanks Shawn. Ground shipment from North Carolina isn't going to happen! I called a local company and am awaiting a response.

Meanwhile the little frit piles I put in the kiln were quite satisfactory. That is they turned out much as Cynthia described, although they were already in the kiln on a kiln-washed shelf with a dusting of alumina hydrate. They looked as though they'd flipped over as the tops were shiny and the undersides retained a granular surface. The AH cleaned off easily with a toothbrush and they are quite stable with no sign of crumbling. The only problem is they look a bit too bright. Might sandblast them to make them a little duller. Jen