[First Wood Fired Kiln Build, Problem Stalling]

Good job! Firing a wood kiln is a very grand dance.     Porcelain is quite delicate and wont hold up to that heavy level  of flame impingement like a good grogged stoneware. It seems they were overfired by a few cones!  You might try to use stoneware pieces to act as a bagwall.     The rebar will sag. Even more so if the coals build up and block the inrush of cool air from underneath .    I see you didnt weld them to the tbar so you could just turn them over each firing and get several more out of them.  I pull mine and lay them on a concrete slab and beat them straight with a sledge hammer.

Keep up the good work and let us know about your next firing.

[QotW: Where and how do you store your clay?]

I use rubbermaid trash cans. I first pug my clay and then put a layer of clay then plastic then another layer of clay so forth and so on. Then several layers of plastic film on the top and then the lid. Occasionally I will pour a cup or two of water inside to prevent too rapid of evaporation as we have quite a dry environment here. The trash cans are put on mover dollies for ease of storage.

[Im desperate]

What Neil said. Do you have sinks or toilets or tubs or showers that havent been used in a while?

[Connecting gas kiln to house natural gas supply]

4 hours ago, Mudfish1 said:

am assuming that the venturi burners just weren't pulling in enough air to burn enough gas to keep heating up the kiln?

This.  One thing Ive found with fuel burning kilns not reaching temp is not enough oxygen. It seems like youve found the correct amount of gas by adjusting pressure up and down. .. but at 5000ft plus above sea level we have way less oxygen per cubic ft than at sea level.

[Type of hypoid oil for pugmill]

Can you get Lucas oil products over there?

[Really old Amoco potter's wheel]

On 3/3/2023 at 8:35 PM, Pyewackette said:

I couldn't find a reverse switch but I'll look again.

Look for it on the bottom of the motor.

[Creating Flat Ceramic Plank]

Drying it sandwiched between two pieces of drywall sheetrock wallboard whatever you call it in your area works fairly well. Make sure its pretty dry before unsandwiching it because if its only partially dry it may still warp. When firing lay it flat on a shelf with fine silica sand under your slab.  ...works fairly well but some of the other fine folks here might have other ideas they can send your way.

[First Wood Fired Kiln Build, Problem Stalling]

16 hours ago, twsincich said:

I figured wood firings just always took multiple days. I now get you COULD fire them faster, just depends on what type of effects your after. I'm happy to ride the firing as long as it takes. 

It can take a long time  if thats what you want you want.  So in my experience burning wood with bark will produce the most fly ash. Im not saying that debarked wood doesnt produce fly ash but not to the extent as bark does. Keep this in mind if youre looking for that effect. It doesnt take lots of time for this to happen. And ash will only begin to melt and form a "glaze" at the upper end of your firing temp.

As far as firing time... if you really dont mind spending 12 plus hours firing (Im getting too old for that) by all means do it. If you want a naturally aspirated kiln then raising the chimney high high high is what you might need to do. It increases draft rate which in turn brings in MORE AIR....  enlarging the firebox and inlet will also bring in MORE AIR.

Let us know how the next firing goes!

[First Wood Fired Kiln Build, Problem Stalling]

4 hours ago, twsincich said:

And now that I have read Fred Olsen's book I do wonder if the kiln itself is inherently too small to be able to burn wood hot enough and have the thermal mass to be able to hold in the heat long enough to even fire to cone 10. 

Im going to say no, its not too small. With adjustments you should be able to get it to c14! The flames off the wood are hotter than that.  You just have to release the btu's stored up in that wood quickly with enough oxygen to burn it.

[First Wood Fired Kiln Build, Problem Stalling]

4 hours ago, twsincich said:

am realizing that I definitely need more air!

More air, more air and more air. If you can force air into the firebox and have that part adjustable  (a motorized fan of some sort with a speed controler) you can overcome alot of the"issues" youre having with undersized intake, exit and chimney size. My suggestion is to do as you proposed...enlarge your exit flue, enlarge the ashpit and forget about the chimney... with forced air chimney height becomes a non issue.  Adding more exterior insulation also helps alot.  When i first built my kiln i had some of the very same problems. It would take 12 to 16+ hours to fire. Ive now got it down to 5hrs +or- to c10 in the coolest parts which for me is the lower back portion .  When the blower was added to force air it cut the time down to 8 or 9 hrs.  Since then Ive changed stacking configuration leaving room for the flame to pass thru more readily along with a few more tweeks to get it to a consistent five hours. And its several times larger than yours at eighty cubic feet stackable space. Tons of wares, shelves and furniture along with the hardbrick mass to heat up.  So keep firing and tweeking things around. Dont worry about making mistakes... its how we learn!

[First Wood Fired Kiln Build, Problem Stalling]

18 hours ago, twsincich said:

Exit flue to chimney: 4.5" x 4.5" = 20.25" sq    <<<<<<   I BELIEVE THIS TO BE ONE OF THE MAIN CULPRITS

Yes. It should be close to intake. Its very hard to make it bigger while firing . The damper will control the size IF its made larger than needed.

18 hours ago, twsincich said:

Another culprit seems to be that my fire grate was only 2.5" off the floor and made from bulky fire bricks that choked up the air flow with coals easily. 

Original area for coals under grate: 291" cubed 

Yes also. You need lots of room under the grates for the coals and to also keep the grates from melting IF youre using metal grates. I try to not let the coals build up more than half of the space below the grates. It will choke off the incoming air and cause stall.  .....wood kilns need LOTS of air to fire correctly.

18 hours ago, twsincich said:

Any comments, questions or suggestions would be greatly appreciated! I am out of my element here so any help would be amazing. 

Adding air with a blower of some sort will cut firing time in half or more and will increase temp IF you make sure youre not under feeding the fire. Overfeeding will also affect but not nearly as much. Watch the chimney exhaust. .. a little smoke at stoke is ok and then see it clear within several seconds is good. Smoke all the time thru firing.. no good. Too much fuel.

Also your wood size is what Id use at the beginning of a firing till about bisque temp. After that its smaller stuff with way more surface area for burning. Take one of your 2x3 pieces and split into 4 pieces. Itll burn way faster and release more btu's quickly.

 

[Clay Body for Wood firing with added matter]

If youre able to get Georgia kaolin (tile #6) ive found when added to your body will flash orange more reliably than other kaolins. Dont know about the chicken grit. What does it consist of?

[G-200 substitution]

Ive switched over to G200eu from custer  2yrs ago on every glaze i make and have had zero problems.  ZERO.

[EPK shortage?]

I believe Georgia kaolin fires even whiter than epk. Not as plastic but in this case doesnt matter much. And its cheeper.

[Can we talk about sustainability please?]

6 hours ago, Bill Kielb said:

y isn’t it mandatory to plant X number of trees every time one wood fires? Just kidding, it’s just a suggestion that I think might make sense rather than try and stop all wood firing.

BOOOOO BOOOOOOOOO! Bad Bill! BAD.

[Building a catenary arch waste oil fueled kiln]

Wood firing doesnt have to be done with a fancy rocket yada yada yada.... grates with plenty of room under them for coals AND a blower setup to force air across the wood works really well and is quite simple.  Easy to fire a large kiln from candling temp to c10 flat in 5hours.

[QoW: What clay body or bodies do you work with. . . .]

I mix my own clay.   Firing with wood is a very harsh environment therefore I need to have a clay body with certain qualities that i doubt i can get out of an off the shelf clay.  I've had to adjust the formula several times over the years as problems pop up most of which are in the mined materials changing causing various problems in the body. The last problem I faced was bloating caused by a grog and too much of one particular clay. Changed that and I'm back on track. .... till the next problem rears its ugly head.  I  dont know if being in control of the clay body is a blessing or a curse. I tend to lean towards the former.

[QotW: Are you Dipper, Pourer, Sprayer, sponger, squirter, or Brusher?]

95% dipper 5% sprayer.   Most of my spraying is with an underglaze followed by a clear overglaze. This is on sculpture pieces that have a whole lot of other things going on and then masked with wax resist.  Spraying and dipping give a much more even and smoother coat than brushing.

[Oribe green]

Hey @ biglou13 if you have old school talc then i would suggest a tea dust. Beautiful glaze and colorants can be added to acheive that dark green. Try John Britt's recipe.

[QotW: Do you fire your own kiln, . . .]

Yes .c10 reduction . My kiln is as manual as it can get and is done strictly by color and cones.   Although Ive tried to get the firing time as short as I possibly could without compromising the kiln or wares, I still have plenty of factors that limit my control .   It has always been a fun friends and family gathering to fire our wood kiln but its a bit like herding cats.... weather has alot to do with the firing also. Decades of firing has taught me one thing. I have SOME control over firing but definately not  like a gas or electric kiln. But thats where the fun lies... the adventure of manual firing.  The adventure of herding the cats to keep the temperature rising  so when we finish we can get to the good food awaiting and the resting calm of knowing we accomplished yet another "successful " firing.

[QotW: Given a new 15 X 20 space for a studio, what would be your first 5 things to do to it?]

Tear down 1 wall and double the size! Then add a storage room for glaze and clay. Then add a storage room onto that for wares green and finished. Then add another space for a retail sales.

[Can I fire hard red firebricks in kiln during low fire operations]

Yes you can fire to 04 with no problems.

[How does she do this?]

To me it looks as if glazes or slip are layered onto a textured piece and then partially removed by sanding or other method then fired. Almost looks like "raindrop damascus " in a way.

[QotW: Weight or volume, which is your preference when mixing glazes?]

I use a digital scale in grams for glazes and a larger digital shipping scale for clay bodies  so.. weight!

[Used old shelf primer and this happened, can you help?]

5 hours ago, LauraLucht said:

The person I spoke to at my local shop does think the brown color will burn off and that this issue is related to the dye in the old product reacting. 

YES.  Id try firing before i went to all the trouble of sanding and scraping.