Getting kiln wash off is making me crazy...HELP

[deborahbur]

I have tried all previous remedies......CDL, Muriatic acid, wet sandpaper.....still can't get all the kiln wash off. Must need a higher temp kiln wash. Who makes it and where can I get it????

Thanks
Deborah

[Mimi Rivera Vellek]

Bullseye makes great kiln wash. and they're one of the Board sponsors. You can get it from them directly.

[Amy Schleif-Mohr]

First what brand of kiln wash are you using. Some are better than others. I used to use High fire, had some terrible experiences. BE solved the problem.

Second what temp. are you firing to? I do high fire work and the kiln wash needs to be re-done every time. I also put it on very thick and mix it like heavy cream.

Finally, if you are still having sticking problems, get a sandblaster and blast it off. I never had any luck with anything else.

Good luck,
Amy

[Jerry]

You've hit one of the big issues with kiln work and we've all had to deal with it. When I do a pot melt or a raked piece, I go to 1700 and face a nightmare with the kiln wash. There are two approaches to the problem and neither work very well, but here they are.

First, figure out how to get it off. I've found that a good paint scrapper followed by aggressive steel wool will get a lot, if not most of it. Sometimes I resort to CLR, which isn't a bad product to use. And finally I'll use Muratic acid sparingly; it WILL dull the front of the piece if it gets there.

The second way is to avoid it in the first place and it depends on what you are doing how you might think about it. For my rakings I can lay out a piece of fiber paper and that will protect me. I can use the thin fire as long as I've got a base sheet of glass under the raking. Pot melts are a different problem because the glass does so much moving that thin fire isn't much use. The way around that issue is, again, to use a base sheet. Then thin fire works pretty well. And even if it doesn't, thin fire is a whole lot easier to clean off the back than kiln wash.

Another possibility that works marginally for me is to put something on the shelf beside the kiln wash. You might try sifting plaster, talc or even mica and all three act like a seperator to keep your glass off the shelf. Each one has draw backs in terms of texture or coloring, but you need to try each to see what you like.

If you are only doing basic fusing, several coats of Bullseye seperator should do the trick. Depending on your glass and your temp, you will need to resurface your mold or shelf as the seperator deteriorates, but you already knew that, right?

Jerry

[Phil Hoppes]

I really don't understand the problem but I don't know the shelves you are using nor the kilnwash. On a mullite shelf using BE kilnwash a simple window pane razor scraper cleans my shelf in about 30 seconds flat. On a fiberboard shelf I just use 200 grit sandpaper and get it clean in about the same time. If you are making your own kilnwash you can get harder/softer depending on the mix of ALoxide and kaloin.

Phil

[deborahbur]

So, what you are saying is if you put a piece of clear glass under the pot drop, you can use thin fire?

[Kitty]

is the problem the kilnwash sticking to the glass, or to the shelf? it sounds like you're talking about it sticking to the glass. if that's the case, and stuff like CRL isn't working, maybe try a different kilnwash, or opt for the sandblaster. kitty.

[Brian and Jenny Blanthorn]

I have tried all previous remedies......CDL, Muriatic acid, wet sandpaper.....still can't get all the kiln wash off. Must need a higher temp kiln wash. Who makes it and where can I get it????

Thanks
Deborah

Try a lower temp n go up slowly / soak

This technology is called

Creapy Fire tm

[Jerry]

So, what you are saying is if you put a piece of clear glass under the pot drop, you can use thin fire?

Clear or colored; it doesn't matter. White and black both make nice backings depending on what sort of border you might be considering. Clear is good if you aren't going to add a border.

I think some of the respondents don't understand that you are having problems with kiln wash sticking to the glass as opposed to not being able to get it off the shelf.

Of all the suggestions, pay attention to Kitty; consider a sand blaster.

Jerry

[Bert Weiss]

It's been a while since I posted my kiln wash story, so I'll try it again. I make my own using 80% flour of alumina hydrate and 20% kaolin. Commercial kiln washes tend to contain those ingredients in a 50/50 ratio. If you are lucky, your pottery supply has a fine grade of ingredients. The edge that the commercial kiln wash makers have is the ability to specify a fine grind of powders. Making your own is cheap though.

When I am firing float glass to 1480, tin side down on a mullite shelf. I mix my wash with water to the consistency of skim milk and paint 1 layer of wash with a wide haik brush, usually in a wavy pattern that ends up in the glass. I have also sprayed it on with a Badger spraygun or a mouth atomizer. I then heat the shelves to dry them out. If they come out white, there will be no problems for me. If you want a smooth finish, spray on a bit more than you need, and after it is dry, rub it with your fingers a bit.

After every firing, I remove the wash using a paper towel or drywall sanding sponge. The kaolin is the binder and by using less, it is easier to remove.

People who use it, swear by Bullseye Kiln wash. You could try and add some alumina powder to the Bullseye to soften it.

As far as removing what you have, try using the abrasive mesh cloth. It is a black loose weave cloth with abrasive on the fabric. Most hardware stores carry it.

The softer kiln wash that is removed every time, is for projects that are fired 1400ºF or higher. When I am washing stainless steel slumping molds, I make 50/50 mix and leave it on for many firings.

There are 2 reasons to remove kiln wash. One is that the Kaolin goes through a physical change above 1400ºF and will leave a white scum on subsequent firings. The other reason is that if you continue to add fresh layers of kiln wash (which works) eventually it will chip off and be very difficult to remove or fix. I like a fresh shelf myself.

[Cheryl]

Bert, have you done any melts or other techniques where the glass is intended to move significantly at a high temp, using your wash? If so, and it worked, I'm a convert!

religiousgirl

[deborahbur]

Sandblasters........what is least expensive and smallest that I can use.

Thanks

[Bert Weiss]

Bert, have you done any melts or other techniques where the glass is intended to move significantly at a high temp, using your wash? If so, and it worked, I'm a convert!

religiousgirl

Cheryl

I think that float glass is somewhat more forgiving than the softer 90 and 96 glasses. I think that the only difference would be that a thicker layer of kiln wash may be necessary for soft glasses.

It's not difficult to make your own wash. Simply go to the local pottery supply and ask for 1 pound of kaolin and 5 lb of alumina. It doesn't cost that much. If you have access to a triple beam, you can buy in bulk and mix your own.

I'd be curious to hear about somebody diluting BE wash with more alumina to soften it up.

The funny story is that I got the 80/20 recipe on a newsgroup years ago. It was wrongly published as the Bullseye Kilnwash recipe. I tried it and liked it and later learned that the commercial washes are 50/50. You can't believe everything you read on the internet LOL

[Lauri Levanto]

When making molds for pot casting (880 C)
I make the innermost spalsh layer of plaster and aluminium oxide in 1:2 ratio.
It leaves a smooth surface - like sandblasted .
Caolin tends to sintrate in higher temps making porcellain
that sticks. Plaster calcinates at 740 C and loses the strenth.
It is easy to brush off

Too much plaster and it develops hairline cracks.
Too little plaster and alumina particles contaminate the glass.

Can I add blueberry juice to make it behave like BE ?
-lauri

[Rob Morey]

I have found two remedies for kiln wash sticking to my glass. I do pot melts and shelf melts so I tend to get a lot of it. First, I sandblast everything and that does it in a flash. If I'm cutting the melt into slices, I have to blast the cut edges to keep from getting devit anyway. What size blaster should you use? That depends on your budget, space and needs. I have also used white vinegar when dealing with smaller pieces. I soak the glass for a couple of days and then use one of those green scrubbing pads or a wire brush and the kiln wash comes off pretty easily. If not, soak some more. If your piece is too large for a container, try laying paper towels over it and soaking them well with vinegar then place it all in a plastic bag over night or even a day or two. Be aware that the vinegar may dull some of your colors. Anyway you go you will most likely want to fire polish afterwards.

Rob

[dee]

[quote="deborahbur"]I have tried all previous remedies......CDL, Muriatic acid, wet sandpaper.....still can't get all the kiln wash off. Must need a higher temp kiln wash. Who makes it and where can I get it????

deb, i use the high fire brand of kiln wash from ed hoy and when i get kilnwash adhering to the bottom of my pieces i soak in white distilled vinegar for a while - sometimes a couple of days depending on what i've got going - works well and quite easy...
D

[Katy Mattice]

HI,
I have been using humidifier cleaner to remove kiln wash from my pot melts. Works great!! Just pour it on full strength and wait a couple minutes. Kiln wash bubbles right up and brushes off with a kitchen brush. No Scrubbing. The brand I use is by Humidiclean. I believe it was purchased at Best Buy when we bought the humidifier. It says right on the label it dissolves calcium scale, lime and rust.

Good Luck,
Katy