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Applying Kiln Wash


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#1 Pugaboo

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Posted 11 June 2013 - 06:20 PM

I'm getting ready to apply kiln wash to my new kiln shelves and am wondering just how to go about it. I thought there was a topic covering this not so long ago but have searched and can't find it. So I have a stack of shelves, small ones 15 inch hexagons and half hexes and a bag of dry powder labeled kiln wash. I don't want to ruin my brand new first kiln and shelves!

Do I just mix the powder with water and brush on the tops of the shelves?
If so how thick should it be?
Do I just brush it on or is rolling it on better?
Any pointers on getting good even coverage?
I apply 3 coats yes?
Do I have to prepare the shelves in any special manner?
How long between coats do I wait? Should I fire the shelves each time in between the coats?
I know not to put wash on the sides or bottoms of shelves. I also know not to put wash on sides of kiln or inside cover of kiln but somewhere read I can or should brush a coat on the bottom of the kiln?

Thanks for any pointers given I really appreciate it.

By the way is there a in depth electric kiln book out there? Most books I am reading give a few paragraphs with very little details and covering all the different methods of firing in 1 chapter.

Terry
The world is but a canvas to the imagination - Henry David Thoreau

#2 oldlady

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Posted 11 June 2013 - 06:43 PM

if you think about the exact purpose of kiln wash it might be easier to figure out your next step. yes, mix it with water so it becomes brushable or rollable.

yes you want it only on the tops of the shelves to protect them from glazes that might run. if some glaze may then run onto the kiln wash during a firing, it will be easier to scrape the whole mess off down to the clean shelf. that is its purpose. then your shelf is not damaged, just add some more kiln wash to the bare spot and continue. undamaged kiln wash, once applied, can last for years without needing refreshing. cover small drip spots when they happen. they will.

no you do not have to fire kiln wash on. if you apply it before a firing, it will dry and protect with the first firing. it dries quickly, just like paint. wait just like painting a wall.

using one of the Dollar Tree rollers (NOT the sponge kind) it will be easy to coat the shelf evenly. you can use as many coats as you like. the purpose is to protect the shelf.

shelves should be free of junk when you do it. sometimes i find mud daubers have worked on mine and i have to scrape them off. if you have a heavy fabric ( i use the leg of an old pair of jeans) just rub it clean. mine are stored on their sides in a dirt floored space so i have to clean them each time because of the bugs that love the dark space behind them.

now that you are thinking about the purpose of kiln wash, rethink your last question. why would you put it on the bottom of the kiln? do you mean the UNDERSIDE (which is how your question reads) or the inside of the bottom? the best way to save the bottom of your kiln is to put a full shelf resting on 1/2 inch posts PERMANENTLY as the first place to put pots. then work your way up.

have fun.
"putting you down does not raise me up."

#3 oldlady

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Posted 11 June 2013 - 06:48 PM

your next question might be "i didn't get it even, what now?" don't worry about it. if it is a little uneven it will not matter. think of it a little like the newspaper you might put down on your good dining room table to allow some small kids to use it to paint pictures on.
"putting you down does not raise me up."

#4 Mark C.

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Posted 11 June 2013 - 06:51 PM

Here's my story on wash

http://ceramicartsda...__1



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www.liscomhillpottery.com

#5 oldlady

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Posted 11 June 2013 - 07:45 PM

Here's my story on wash

http://ceramicartsda...__1




mark,
let's not confuse her. all those scary, complicated steps in your post are not what she needs to do. she is firing an electric kiln and using brand new shelves. it is true that the excess wash may slop over the edges and they will need scraping off while damp (so it is easier).

does anyone have a good kiln wash recipe for that situation, cone 6 electric kiln? i think i asked for this last year but the end result was nothing.
"putting you down does not raise me up."

#6 Mark C.

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Posted 11 June 2013 - 09:01 PM

My simple recipe is
1/2 alumina hydrate
1/4 EPK
1/4 calcined (just bique fire it in a bowl) EPK
Use a roller of your choce (small for small shelves) to apply-thin this like heavy cream (1/2 and 1/2)
roll on 1 coat let dry completely-sun will speed this up
roll on one more coat let dry-sun will speed this up
scrap edges the shelv with pots on them- then glaze fire with pots for optimnum results (less fallout)

Ok this is my simple version for everyone with an electric firing from cone 06-thru cone 10-this will work for it all
and it been road tested and quaility assured.
Mark
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#7 Pres

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Posted 11 June 2013 - 09:20 PM

I'm getting ready to apply kiln wash to my new kiln shelves and am wondering just how to go about it. I thought there was a topic covering this not so long ago but have searched and can't find it. So I have a stack of shelves, small ones 15 inch hexagons and half hexes and a bag of dry powder labeled kiln wash. I don't want to ruin my brand new first kiln and shelves!

Do I just mix the powder with water and brush on the tops of the shelves?
If so how thick should it be?
Do I just brush it on or is rolling it on better?
Any pointers on getting good even coverage?
I apply 3 coats yes?
Do I have to prepare the shelves in any special manner?
How long between coats do I wait? Should I fire the shelves each time in between the coats?
I know not to put wash on the sides or bottoms of shelves. I also know not to put wash on sides of kiln or inside cover of kiln but somewhere read I can or should brush a coat on the bottom of the kiln?

Thanks for any pointers given I really appreciate it.

By the way is there a in depth electric kiln book out there? Most books I am reading give a few paragraphs with very little details and covering all the different methods of firing in 1 chapter.

Terry


I mix commercial kiln wash to the consistency of thin tempera paint, or chocolate milk. I put on 2-3 coats using a brush making certain not to get it on the sides or the bottom. When it gets pitted, put on another coat. I like it thinner, and apply two coats for evenness. I often have tall pieces with narrow bases, and with to have the most solid even foot area in the glaze firings.

Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#8 Benzine

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Posted 11 June 2013 - 10:33 PM


I'm getting ready to apply kiln wash to my new kiln shelves and am wondering just how to go about it. I thought there was a topic covering this not so long ago but have searched and can't find it. So I have a stack of shelves, small ones 15 inch hexagons and half hexes and a bag of dry powder labeled kiln wash. I don't want to ruin my brand new first kiln and shelves!

Do I just mix the powder with water and brush on the tops of the shelves?
If so how thick should it be?
Do I just brush it on or is rolling it on better?
Any pointers on getting good even coverage?
I apply 3 coats yes?
Do I have to prepare the shelves in any special manner?
How long between coats do I wait? Should I fire the shelves each time in between the coats?
I know not to put wash on the sides or bottoms of shelves. I also know not to put wash on sides of kiln or inside cover of kiln but somewhere read I can or should brush a coat on the bottom of the kiln?

Thanks for any pointers given I really appreciate it.

By the way is there a in depth electric kiln book out there? Most books I am reading give a few paragraphs with very little details and covering all the different methods of firing in 1 chapter.

Terry


I mix commercial kiln wash to the consistency of thin tempera paint, or chocolate milk. I put on 2-3 coats using a brush making certain not to get it on the sides or the bottom. When it gets pitted, put on another coat. I like it thinner, and apply two coats for evenness. I often have tall pieces with narrow bases, and with to have the most solid even foot area in the glaze firings.


That's essentially what I do, but I'd say I mix it to a consistency of "thin" chocolate milk. I found, that when I first started teaching, I put the wash on too thick, and it would crack/peel off after a couple firings. I think I was trying to put it on thick enough, so that the shelves would be very well protected. What I didn't realize was, it really doesn't have to be all that thick, to protect the shelves.

I alternate the directions between coats as well. One going horizontal, the next vertical, then again horizontal. I however, do wash the edges of the shelves, in case a piece is sitting near enough the edge, to drip. I, of course, do not do the bottoms of the shelves. Sadly, I've inherited classrooms, where previous instructors, didn't follow the same steps. I've seen shelves, with both sides washed, glaze drips on both sides, etc. That reminds me, I need to order some new shelves.....and posts....
"Anything worth believing, is worth questioning"

#9 Pugaboo

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Posted 11 June 2013 - 11:01 PM

Thank you Oldlady, Mark and Pres.

Oldlady - I'm sorry I guess I typed what I knew I meant not what it sounded like? I meant the inside of the bottom of the kiln, the floor part inside where you would sit stuff on. The kiln is fairly small with a chamber about 15x23 so not sure if putting a whole shelf in there just above the bottom is feasible. Will try it out and see I guess. Speaking of newspaper or paper at least ... what is Kiln Liner Shelf paper? Do I need this? Saw it in a catalog and got to wondering if I need to use it or not.

Mark - YES that's exactly the topic I was trying to find again thank you for posting the link. I think I will move the shelves into the studio where I have a dehumidifier to make sure shelves are as dry as possible. They've been sitting in garage and its been raining like mad for days. If its sunny I'll try and find a safe place to lay them out outside instead. Also thanks ou for the recipe I will add it to my glaze recipe notebook so as not to lose it. In your recipe am I right in assuming I take regular EPK and bisque it to ge the calcined EPK yes? When I get braver I'll try a homemade batch of wash... To chicken for that yet!

Pres - I plan to start with the commercial wash that came with the kiln so knowing the consistency you use is a big help. I tend to do a lot of smaller items so am thinking like your tall narrow items a smoother surface might be best for me.

The electrician is due here in the morning to run the breaker, wiring and shut off switch. After that I'll be able to finish setting up the kiln imstalling its vent and all and be ready to fire it up. I have been making up stuff in preparation of the electricians arrival. Nervous and excited does not begin to describe it!
The world is but a canvas to the imagination - Henry David Thoreau

#10 justanassembler

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Posted 12 June 2013 - 01:11 AM

When people say that thick applications of wash tended to crack, this really has everything to do with what is in the wash. I have found that washes with higher percentages of calcined kaolin crack less because they shrink less--youll need to experiment a bit--the good news is that the worst thing that happens is it flakes off and you have to re-apply.

#11 oldlady

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Posted 12 June 2013 - 09:47 AM

ohfergoshsakes!!!!!!!!!!!!kiln liner shelf paper!!!!!!!! what next??????

you do find some strange stuff to read,pugaboo.

has ANYONE else heard of this?
"putting you down does not raise me up."

#12 timbo_heff

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Posted 12 June 2013 - 10:02 AM

Shelf paper is for glass firing:
Best practice for kiln wash is 3 fired on coats per below;
The prob with the stuff is that you can't flip your shelves which will extend their life. I think better to dry foot, use stilts, and or when you throw the foot area of your pots : leave a little glaze catching edge (but not always practical or aesthetically correct)
Here is best practice though:

DIRECTIONS FOR USE
Kiln wash is applied to kiln shelves to protect them from glaze drips. On a washed shelf, drips can be easily removed without gouging or marring the kiln shelf.
Mix the kiln wash with water to a thin cream consistency. Apply only one coat at a time. Use a wide paintbrush or utility brush (a 2" - 3" wide, soft bristle brush generally works best). Three individually firedon coats of kiln wash are preferable.

APPLYING KILN WASH
1) Make sure the floor of the kiln and the tops of the shelves are coated with kiln wash. This will protect these surfaces from melting glaze and ceramics.
2) Do not coat the bottom or sides of the shelves.
3) Do not apply kiln wash to the brick sides or element holders.
4) Apply the kiln wash to the thickness of a post card.
5) The only purpose of kiln wash is to prevent any glaze that drips from a piece from sticking to the floor or shelves. This saves both the piece and the floor or shelves. If dripping should occur, simply remove dripping and cover the spot with new kiln wash.
6) When you are applying kiln wash to your shelves for the first time, it helps to dampen the top of your shelves with a wet sponge or a water-filled spray bottle first. This makes the kiln wash go on easier and more evenly.
7) For the kiln wash to really protect the kiln shelves it is best to apply three separate coats. In addition it is best to fire each coating separately. (If you brush one coat on, let it dry and then brush on another, you could actually be brushing off the first in the process, so ideally each coat should be fired on). The shelf can be used while firing the kiln wash on, so theoretically you would put one coat on, load the shelves and do your test firing of the kiln. The second coat would be fired on in the first bisque and the third coat in the second bisque or first glaze (whichever comes next). Fire at least to cone 018 - hot enough to give the kiln wash enough adherence to the shelf to prevent it from coming off in the second coating. Note that some people
get away fine without three firings of the kiln wash. However, we include this recommendation as a “best practice”.
8) If you notice that your kiln wash is flaking off, use a paint scraper (or something similar) to remove any loose bits, then reapply kiln wash. If glaze drips ontoyour shelf, use the paint scraper to pop the glaze drip off and clean up any loose areas around the area, then dab some more kiln wash in the bare area.

PROGRAM TO QUICKLY DRY KILN WASH
Here is a program that will dry the kiln wash in a hurry:
In the Vary-Fire section:
Press Enter Prog, Press '1'
Press Enter, Press '1'
Press Enter, Press '60'
Press Enter, Press '200'
Press Enter, Press '600' (for 6 hours, 400 for 4 hours, 800
for 8 hours etc of hold time at 200 degrees)
Press Enter, Press 9999
Press Enter, Press START

#13 Arnold Howard

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Posted 12 June 2013 - 11:04 AM

Thank you Oldlady, Mark and Pres.

Oldlady - I'm sorry I guess I typed what I knew I meant not what it sounded like? I meant the inside of the bottom of the kiln, the floor part inside where you would sit stuff on. The kiln is fairly small with a chamber about 15x23 so not sure if putting a whole shelf in there just above the bottom is feasible.


You should apply kiln wash to the kiln's firebrick bottom. Be careful not to get kiln wash into an element groove. The kiln wash should last for years and will help to protect the bottom from glaze should you ever overfire the kiln.

Sincerely,

Arnold Howard
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ahoward@paragonweb.com / www.paragonweb.com

#14 Arnold Howard

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Posted 12 June 2013 - 11:09 AM

what is Kiln Liner Shelf paper? Do I need this? Saw it in a catalog and got to wondering if I need to use it or not.


I've used shelf paper but prefer kiln wash. The shelf paper is used in glass fusing. The side of the glass that goes toward the kiln shelf picks up the brush marks from kiln wash. The shelf paper leaves a smoother surface on the glass. The paper is fairly expensive; I don't believe it is ever used in pottery.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
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#15 Nancy S.

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Posted 15 June 2013 - 09:15 PM

I remember reading somewhere that you should flip your shelves with each firing, so the kiln wash should go on both sides. I have no personal experience with this, so....anyone? How true (or necessary) is this?

#16 oldlady

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Posted 15 June 2013 - 10:35 PM

I remember reading somewhere that you should flip your shelves with each firing, so the kiln wash should go on both sides. I have no personal experience with this, so....anyone? How true (or necessary) is this?




NO! NO! NO! NO!

with lots of heat ( above cone 6) and time, a lllllooooonnnnnnggggg time, a shelf may warp a little out of level. IN THAT CASE>>>>>>>>you might turn the shelf over after scraping off, grinding off and totally removing any kiln wash. then use the bottom side as though it were a new shelf. NO NO NO NO not all the time and NO NO NONONO do NOT put kiln wash on the underside of shelves!!!!!

i can show you what happens when a small flake falls onto your best work!!!! NO NO NO!
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#17 Mark C.

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Posted 15 June 2013 - 10:47 PM

I remember reading somewhere that you should flip your shelves with each firing, so the kiln wash should go on both sides. I have no personal experience with this, so....anyone? How true (or necessary) is this?


DO NOT WASH BOTH SIDES_-REPEAT DO NOT WASH BOTH SIDES
OK we cleared that up-By the way if you do wash both sides you will reget it every glaze fire from fallout siticking to your wares.
Mark
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#18 clay lover

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Posted 16 June 2013 - 07:17 AM


I remember reading somewhere that you should flip your shelves with each firing, so the kiln wash should go on both sides. I have no personal experience with this, so....anyone? How true (or necessary) is this?


DO NOT WASH BOTH SIDES_-REPEAT DO NOT WASH BOTH SIDES
OK we cleared that up-By the way if you do wash both sides you will reget it every glaze fire from fallout siticking to your wares.
Mark


I have not washed my shelves, I try to put a foot on everything, but sometime test glazes do run off. I had been warned about the warping issue. Now, several years later, I wish I had, my shelves are a bit sloppy looking with patched of wash over ground off run spots. think I will do a THIN application just for safety sake. I am using all 1/2 shelves, and am assuming they will be much less likely to warp with no turning.

I had never heard of washing the bottom of the kiln. in that vein, how close to the bottom-floor can I put my first shelf? I had been taught 2", but that puts the shelf above the 1st element.

#19 Kohaku

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Posted 16 June 2013 - 09:43 AM


I remember reading somewhere that you should flip your shelves with each firing, so the kiln wash should go on both sides. I have no personal experience with this, so....anyone? How true (or necessary) is this?


DO NOT WASH BOTH SIDES_-REPEAT DO NOT WASH BOTH SIDES
OK we cleared that up-By the way if you do wash both sides you will reget it every glaze fire from fallout siticking to your wares.
Mark


Huh. I guess I'm betraying my self-taught ignorance here... but I flipped an older shelf earlier this year (now with wash on both sides.

So far so good- nothing's fallen on a pot, and that's after about 20 firings. I guess there's a better angel looking out for the uninformed?
Not all who wander are lost




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