First Time Wood Kiln Fireing Questions

[Jawpot]

I have helped with about 15 wood firings so i know just enofe to get my self in trouble and I hope to take my first try at trouble in the next 45 days.  I have just about finished the building of my first anagama kiln.  We plan on firing the kiln about 6 times a year.

 

Question #1.  I plan on coating the inside of the kiln with ICT 100 HT before the first firing.  Should i coat the inside of the kiln between each of the first few firings?

 

Question #2.  All the bricks have been kept under a roof scene delivery.  I do plan on burning a few gallons of propane with a weed burner in the fire box the week before I load it.  I know to stick to the firing schedule, but anything else i need to know about the first firing?

 

[Mark C.]

Question #1

light  thin coating before the 1st fire and then forget it. If its soft brick then I have some other suggestions?

[Jawpot]

We went with all hard brick.

 

Thank you

[Marcia Selsor]

ITC is a great product. You are suppose to dilute it and spray with a sand blaster sprayer. It works well if someone has a drill stirring while someone else sprays. It does settle fast.

You just need a light coat as Mark said.

Marcia

[Jawpot]

Last week when i was in the city i picked up a cheep sand blaster that has a 25 lbs open top hopper.  I'm not sure if my 4 cfm at 90 psi is going to be able handle this thing.  I'm going to put some feelers out for something larger i can use for an hour.  I do have a 30 amp, 3 phase, 4 wire, Y panel at the kiln, but would like to use a gas compressor if i can find one.

 

I have read about using ITC in a few books.

 

Thank you

[Mark C.]

ITC should be applied with a suction sand blaster-Harbor freight and axone sold them. Not that top loader you describe . It sucks up the fluid in a hose. It takes an air compressor to power it. I use my larger compressor. I have sprayed over 10 gallons of this stuff on just about any surface.-Thin coatings is whats best. Have two people as noted in above post. One stirring with a power drill and one spraying. You should follow the directions 1/2a bucket of water with 1/2  bucket of ITC.

good luck

You never said all-hard brick or some soft brick?

[Marcia Selsor]

I agree with Mark. It is a two person job for the best results.I have done it with one hand on the drill and the other on the sand blaster. Tricky and awkward.

Marcia

[Jawpot]

The sand blaster i got is a suction feed.  It's like the $79.99 harbor freight one, but has a smaller container.

 

It's all hard brick.   

[Guest JBaymore]

If it is all hard brick, do NOT coat an anagama with ITC.  You WANT the ash buildup over time.

 

Dry fire the kiln to at least bisque temps before doing an actual loaded firing.  If you used castable on the hot faces areas in any locations in addition to the hardbrick... you need to follow the castable instructions for the firing cycle and fire that stuff before the ware load firing.

 

How large is the anagama?  True anagama or a tube type kiln (cat or similar)?

 

best

 

.............john

[Mark C.]

John do you want ash build  in the fireboxes or would some ITC help there?

[Guest JBaymore]

John do you want ash build  in the fireboxes or would some ITC help there?

 

You want ash buildup pretty much everywhere.  Main firebox floor and the VERY lower side walls and the sidestoke firebox floors usually get washed repeatedly (zirconium/alumina works fine).... but since most folks stack stuff right in the fireboxes... nothing on the "above and around the work" area.

 

Typical anagama get better results with each firing as they "season". 

 

ITC does work for salt/soda... ...I've used it for clients..... and if it were a soft brick hot face I'd say for SURE coat it.  But not on hardbrick.  Talk to Fritz..... ITC 100 HT was not made for either hard refractories application OR for anything other than brand NEW IFB.  And yes... THIN coating is the answer with that stuff.  More ITC is NOT better.

 

Yes... the anagama kiln is slowly "dying" as the ash eats into the bricks and starts to melt the hot face.  Cost of doing business. 

 

From the woodfiring work I've done at the really busy woodfire place in Japan... we have a pretty good idea of the longevity of really good refractories in repeated long duration (4-7 day up-cycle) wood firings to cone 14.  A really good SK32 DP brick (about equiv. to US Super Duty DP) will last about 150 firings. 

 

My own noborigama here in NH looks to fit that number of firings model pretty closely also with good US materials.

 

So....... that kiln of Jawpot's will still last a while if it was built well.  About 25 years or so at 6 per year if they go hot and long.

 

best,

 

...............john

[Jawpot]

The fire box is 4' by 6'.  The work chamber is about 18' by 6' and starts off 5' 8" high and the last step is about 3' high.  We dropped the fire box down 3' because I want to be able to get some firings with very low amounts of ash travel.

 

It's a close copy of something work with in Japan in 1995 that fired for 52 hours.  There is one in Alabama that has one that's all most identical to what i built that my grandfather helped fire a few times over the last few years that fires to cone 11 in 36 hours.

 

Monday i should be getting the bracing delivered for the chimney and i still need to cut a hole in the roof and finish building out the height.

 

 

 

This is my grandfathers build and i'm more or less just in for the ride and to do a ton of labor.  I wanted to build a 3 chamber climbing kiln.

[Mark C.]

One note on Fritz is he sold the company a few years ago. The stuff doubled in price.

[Guest JBaymore]

One note on Fritz is he sold the company a few years ago. The stuff doubled in price.

 

Yeah... I know.   Sort of like "Big Pharma". 

 

best,

 

...........john

[Guest JBaymore]

Decent sized anagama.   Should be fun.

 

 

  I wanted to build a 3 chamber climbing kiln.

 

 

    

 

Where in Japan did you work?

 

best,

 

...............john

[Jawpot]

 

One note on Fritz is he sold the company a few years ago. The stuff doubled in price.

 

Yeah... I know.   Sort of like "Big Pharma". 

 

best,

 

...........john

 

I have to take 2 shots a month.  It's only $7,000 a month without insurance.  I tried about every other drug, but nothing worked.  

 

I was in Arita Japan for about 6 months.  I have traveled around the world a lot spending a month or so at different places before my dad made me stop and work for him.  I was a fly on the wall at the Leach pottery when they loaded, fired, and unloaded there kiln.

[Guest JBaymore]

 

I was in Arita Japan for about 6 months.

 

Nice.  I've never made it to Arita.  It is on the "to do list".  Unfortunately... there is still a lot on that list even with all the time I've spent in Japan.  .  Hope I make it someday.  Getting old.  .

 

I assume that when you said "low ash" (and the comments about a nobori) that you are hoping to run the back with glazed ware?

 

best,

 

...................john

 

PS:  I hear ya' on the prescriptions.  It is tough.

[Jawpot]

Yes i was planing on doing a lot of glazed ware.  I love to make a lot of large stuff, it's hard to fire in our electric kilns, and i can not keep it in our shop.

 

When i was younger i was all for traveling.  Now when i fly i get ear issues that don't go away for weeks and don't like to drive more than 400 miles in a day so i don't travel much any more.

[Jawpot]

Monday morning i lit the sucker up empty.  A few of us switched off loading wood in it for 16 hours and got it up to 2,180 in the front and 1,950 in the back before we sealed it up.

 

Today were glazing up all of our larger stuff and plan on loading part of Wednesday and Thursday so we can light it up first thing Monday.

 

We had some draft issues for about the first 2 hours.  I'm thinking about tossing a weed burner in the fire box on low the night before we fire it up.  There calling for humidity to be below 55% for the next week and most of the stuff is green wear.

 

I have butterflies, but at the same time I just want to get the first load done and over with.

[Guest JBaymore]

Did you leave a "cleanout port" in the base of the chimney? 

 

If so.... build a charcoal briquette fire in there for a good long while before you light the sucker up loaded.  That should solve the draft issue in the early stages if you don't want to prolong the overall firing using only wood on the firing.  You could also stuff the weed burner in there instead.  (The charcoal fire is more "aesthetic" .)

 

A VERY slow low fire on the front end of the cycle will establish the draft slowly... but it sounds like you do not want to run a longer cycle on this kiln.

 

Have a GREAT firing.  Keep us posted of the results.

 

best,

 

................john

[Jawpot]

There are dual 8" by 8" clean out doors in the chimney.

 

I thought about putting a tinny fire in the chimney.  We started the fire before the sun was on the chimney and i think an hour of sun on the chimney would of done a lot of good.  We were also loading up to start a pit firing (5' by 4' by 20') and was not paying a lot of attention to the kiln at the beginning.

 

The firing time is something that's going to kill me the first few firings.  No one wants to help until we can show what it will produce and I need to keep 2 potters in the studio when were open 3 days a week (large windows where people watch).  Once we have a few good firings i plan to hire my brother (a thrower) and passably his wife (for prepping stock and for the shop) that will solve a lot of issues.

 

I was thinking about using a weed burner as a long slow heat should help to drive out a lot of moisture most of the items will not be bisqued.