QotW: How often do you vacuum out your kiln and sieve your glazes?

[Pres]

I have been fifing some pieces for next season, and Christmas of late. On the last load, I found a rough piece of clay inside a glaze fired bowl. About 1/32 long, I wondered how it got there. I had recently vacuumed out the kiln, so I was puzzled about what happened. Looking closer the piece seemed to have glaze around it. I sieved all of the glazes again once to a clean bucket then back to the original. Re-vacuumed the kiln and hope that the next firing will be different.

QotW: How often do you vacuum out your kiln and sieve your glazes?

 

best,

Pres

[Denice]

I vacuum out a kiln when the bottom starts to gets speckled looking or a pot shatters in a bisque firing.   I sieve my glazes before I use them if they have been sitting on a shelf for a long time.   I tend to jump around on glazes so I probably sieve them every time I  use them.  Maybe you got a piece  clay stuck on your sleeve and it fell off when you were loading.        Denice

[Mark C.]

I vacuum electric when I work on it  or it needs it but in last two years I have only fired it once so no need. 

Glaze get seived whenever I make them thru a 80 mesh talisman.

I just mixed 5  gallon buckets last Thursday and seived them into my 30 gallon bucket

I'm in the middle of a huge rutile pitting and ugly period so lots of testing going on now for me. In my 50 years never had so many rutile issues  this past year.

Edited September 25, 2023 by Mark C.

[Min]

40 minutes ago, Mark C. said:

I'm in the middle of a huge rutile pitting and ugly period so lots of testing going on now for me. In my 50 years never had so many rutile ussies this past year.

What changed? New batch?

[Kelly in AK]

The soda kiln gets vacuumed every firing. There’s plenty of stuff flying around in there, I don’t need anything extra to ruin my pots (While I’m at it, shelves get scraped and lightly washed every time as well. Silicon carbide shelves.). Electric kiln, very seldom. Once a year. 

Glazes get sieved when I see chunks while glazing. Some glazes do form agglomerations. When the glaze dries and there’s little bits sticking up, that’s my sign. Those bits don’t always dissolve into the melt. 

[Mark C.]

3 hours ago, Min said:

What changed? New batch?

Not much ,old, new and brand new batches all doing it. Swapped clay bodies ,changed firing cycles. Stll not got it naild down-all kilns as well.. Its been over a year now and I'm at wits end.My materials are all old as well so not new stuff-big mystery 

I have had a few other professional potters call me with same deal so its a bit widespread

Edited September 25, 2023 by Mark C.

[Min]

Are you using the rutile for its visual texture only or for its colour also? I recalculated my recipes using titanium dioxide in place of rutile as I use it for visual texture. (Sorry about going off topic here Pres)

[Roberta12]

I vacuum the kiln every couple of months, I guess.  But I sieve glazes every time I use them.  I just find application is better if I do.  

 

[Hulk]

Vacuum when there's new bits/dust; if I'm careful, that's not often.

Sieve every time, unless I'd sieved and used the glaze within the last few weeks, and I'm sure there's no bits/chunks/things dropped in there...

Edited September 27, 2023 by Hulk
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[Callie Beller Diesel]

Vacuuming my kiln: I plead the fifth. Don’t do what I do, kids.

Sieving: definitely as I make them, and if they’ve been sitting for several months unused. That latter doesn’t happen much anymore, but worth mentioning.  I try and keep my buckets clean and wiped down because sieving usually winds up with more on the floor than I want. 

[Mark C.]

On 9/25/2023 at 7:22 AM, Min said:

Are you using the rutile for its visual texture only or for its colour also? I recalculated my recipes using titanium dioxide in place of rutile as I use it for visual texture. (Sorry about going off topic here Pres)

I have made much of my living off Rutile color . Its my best selling glaze by far. Visual texture is not what they want from me its the blue which is also over my black glaze which is super striking (none of this is my favorite  color by the way) that said I need the color. My 50 # bag of rutile and my spare 50 # bag is many decades old so it not anything new.

I have been using this glaze since 1972 and its been through a bunch of ups and downs but this is the longest down I have had ever x 2. I have had Laghuna make it by the ton for me for over 35 years now. I mixed my own last few fires and that did not help -all with old world materials-The new geil did pit less but its just a fluke to keep me in the game.

I'm off for 5 weeks  now and will get back to refiring and smashing  pitted rutile work in Nov. I will soak my sorrows in tropical fish waters soon. I have had to professional potters contact me about same issue lately so its like a flue and is going around.

[Hulk]

The soaking can't hurt!

As for the pitting, any chance the clay(s) have changed at all?
Do the glaze recipes Laguna do for you include talc?
Just curious...

[neilestrick]

The kiln should definitely be vacuumed if anything blows up in it or there is an obvious need for it, but beyond that I haven't seen any proof that regular vacuuming has any effect on element life. I rarely every vacuum out my kilns except when I change the elements, and they get the expected element life. I do enough kiln vacuuming during repair jobs that I have no interest in doing it at my studio unless I really need to.

I only sieve my glazes when I mix them.

I'm lazy.

[Mark C.]

3 hours ago, Hulk said:

The soaking can't hurt!

As for the pitting, any chance the clay(s) have changed at all?
Do the glaze recipes Laguna do for you include talc?
Just curious...

yes and I know what kind they used. I use the same Pioneer /texas talc for that glaze as well.  I have a supply of many different talcs for specific glazes. This one is my only Texas talc one.

[Min]

13 hours ago, Mark C. said:

I'm off for 5 weeks  now and will get back to refiring and smashing  pitted rutile work in Nov. I will soak my sorrows in tropical fish waters soon.

Have a great trip Mark! 

When you get back it might be worth trying some titanium dioxide + iron or iron silicate and see if that works. Either way it could rule in or rule out one of the variables.