Mark C.
-
Posts
12,010 -
Joined
-
Last visited
Content Type
Profiles
Forums
Gallery
Posts posted by Mark C.
-
-
I use a shop blender for all zinc =think zinc margarita and blend away then add that measure beaten zinc to bucket and sieve normally.
-
The easy fix is use a liner glaze on inside and ash glaze on outside-issue is done.
If that sound to hard (an inner and outer glaze job) try- below
Since you are using a iron clay a hotter bisque any help by making sure all organics are burnt out
yes it looks like the glaze is peeled back clean to me as well. burnouts or ash peeling it back is my guess. Even in oxidation as Kelly said the inners are a slight more reduction or lets say not as oxidized. One nice liner glaze inside will fix this in a heartbeat
-
That kiln has had a short hard life
-
6 minutes ago, Burnt Earth said:
Thanks. Do you guys just leave a gap in the chimney that you slide them in?
I meant mullite and the slot is usually 1 inch with a 3/4 inch thick kiln shelve. My Girl kiln is less and used a 5/8 shelve in a 7/8 slot.
Not sure on your steel stack how you are are going to do this. The damper rides on 3 sides the two sides and back to close . In the front slot it sticks out enough to run cool Never used one that was less than 18 inches long . You need expansion space and if the shelve warps that also need space so not to tight
-
Mullet kiln shelf in my 4 gas kilns for a damper
-
You could empty the mixer and let the bottom dry out and get it out that way and rehydrate it again in small pieces.
welcome to tne forum
-
wow Neil said it best ( it'll likely be glowing orange outside the kiln) I will add in no time fast. You need a damper in the chimney they work best about waist height. As he said natural draft burners need the stack (chimney) to be tall and even with your 4 feet more of steel its still way short. I have a stainless steel stack after 8 feet of brick on two kilns. look for that stuff at a salvage yards near beer or pulp mills or any large plant that uses stainless piping. 3/8 is good but still not good enough-Yes you can get some life from it but you still need a damper and way more height. You can get a fast fire in maybe 8 hours -remember the furniture need to take the heat and cooling as well. I'm not talking lawn chairs I mean the kiln shelves and posts
now to answer the other questions-I would put a digital thermcouple in the door so its swings out of the way and is not in the burner direct path.
If you want to be fancy (i use oxy probes) a oxygen sensor will last longer in the chimney except in your case it may not as the flue flow is so tightly contained. The new to be geil I palces my probe in the flue as it will last many hundreds of fires before burning out. My other two gas kilns have the sensors in the middle of the load in the doors. They get all of cone 11 so they do burn out in a few hundred fires. I fire a lot every year over the past 50 years and have a few platinum elements replaced
If you are a beginner really just a good eye is all you need for reductiuon firing-a potter who knows thier stuff would be an asset on the 1st firing or two.
Most newbies put to much gas in thinking more is better-this is where the cheap digital pyrometer come in as it show the exact temps going up or stalling. You need one that goes at a bit more than the cone you are firing to..
You need to keep that kiln dry-no rain or snow on it-ever as soft brick and fiber are like sponges and once you dry them out (slow start the 1st fire to dry it out) you want it to stay dry.
What is the flue dimension 8x8?
-
In the 70s silica and talc where what they where-no body knew that silica was 200 mesh or 325-the bags did no say much on them. When I asked most supoppliers only stocked 200 mesh (cheaper) All my silica was 200 mesh.. In the 80s I traded it all to a glass blower for his 325 mesh silica. Later in years the 325 became a thing in many other materials . When you bought talc in 1975 you asked for talc and you got a bag. (Neph syn was always in 200 or 325 mesh and was the odd one in this choice)There where zero choices. Life was simpler then no shortages, basic commodities, Like coffee now you can have it with 1/2 low fat 1/2 or 2% or all fat or almond milk or austrialian nut juice-well you get the point wayyyy to many choices
In those days the talc was desert talc from Death valley (long ago closed up) or c talc. That has all changes now as well. Texas talc was a major shift for decades-talc which is grey in color. I now use 3-4 talcs . I only use the 325 in most materils if there is a choice for better melts and yes in the 70s cone 6 was not a thing but 06 was a thing. Back then we had what we called old lady slip shops that sold cone 06 stuff and did mold work (this area had 3 of them) and I got a wholesale accout at one for some materials and tools(all long gone for 35-40 years now) I knew of NO cone 6 users in the 70s and 80s-none only in the 90s did I become aware of that temp range. Now I should add I'm in a very high electric rate area maybe the highest in the counrty (Maine I think is higher).
Its made ordering materials overcomplicated as well on my side as well.
-
The answer is #3
#5. The kiln will stink more than usual as well
# 6 try it and learn .
School of hard knocks has the best lessons
-
The 2 inch is best -more insulation is always better
If that rod is subject to lots of heat I would use stainless steel as it will not corrode like steel does, if its a low heat (well insulated around it mild steel is fine. My guess is, it got hot and flue gasses made it corrode to dust. now if you are going to fire kiln on a hobby basis then steel will last fine ,but if its a kiln that will be used all the time stainless is worth the cost. Thicker steel hold up longer than thinner steel
These use factors play a big part in how well things hold up.
-
90 weight is my best guess
-
I think they have some cheaper materails as well-like tin
-
Looks like the roof just needs some steel angle iron on top with new buttons and wire to hold roof up.
-
Its been raining for weeks in the low 50s and it finally broke up with sunshine for two days and 70 degrees yahooo. Great day for driving south and return drive north. Then by Tuesday its a atmospheric river with lots of rain predicted again. We had 4 inchs on the 13th in one 24 hr period. Rain forest for sure. We are up to 32 inches since October 1st.
-
I have zero plans for pot shop work for February. March is a big maybe?
I painted the wood floor in throwing room just after xmas as the industrial paint wore though in the traffic areas in the last twenty years. That was a big job getting all the throwing area empty then extra mopping and drying and sanding, then two coats of really nasty heavy duty floor paint which is grey and I had 3/4 of a gallon left over from twenty years ago when I built the throwing addition and painted the floor before the walls went up . I wore the super duty resperator where no smells get through to do this job and had doors open whenever it was not raining for weeks. .
That said I threw two kiln loads and fiired them in January for backstock to last through Feb and March. for my outlets
Today I head south for 4 hours to Santa Rosa to have a tarrsal tunnel sugery on my right foot in early am on Monday . (its like carpel tunnel only on the foot (ankle area is the compression area) This is about twice as hard recovery from carpel tunnel surgery I'm told . Both my feet are numb on balls ,one for a year so I'm trying this 1st foot to see if it works. If it does I'll do the other foot later. The cast stays on for 3 weeks and my foot cannot touch the ground for those 3 weeks. I have a knee scooter and crutches and will be laid up on pain killers for a spell. I hate drugs.My rehab starts in 6 weeks from tomorrow (mid March)so no pots being made. The nerve gets compressed just like in carpel tunnel so they cut the sheath to allow the nerve more room. PS ,I never have had carpel tunnel but know all about it from my wrist surgeons and friends who had that surgery
I did throw a few salt cellars yesterday with some spare time on my hands.I'll need 80 of them by spring
I will order some tools from Laguna so that a bit of clay stuff when I'm off the pain meds. The tool order is mostly for others as Kemper tools may be gone soon as I noted in post last month.
I have some tax work lined up as well as a pile of books to read-none are about clay
I will have a huge wholesale order to do when I get my foot back but it will be late March at best. That order is every spring and it a Subaru with about 20 boxes of pots.No idea when that will get done this year at this time. Its my last day today with two good feet
Clay work is on hold for me for most of those two months
Getting old is not for the faint of Heart
-
The pot looks really thick where the blowout occurred. That to me means it was to damp for your firing cycle (to fast ). Moe dry time and less thick pot (more trimming)
-
Just a question about the inside hot face. This is from talking about another Lazeer kiln. repair post. Is the hot face all fiber as your photos sort of shows or is some stiff ceramic board also in the hot face-like lid or back wall? From your photo all I can see is fiber but it does not showm all the walls and lid.
Thanks
-
-
For some reason may new users seem to stuggle with these units when they first use them
This is one in many other with same issue that does go away after some use-I think they figure out how to use tham over some time
-
Shimpos take a beating and keep on thumping
-New marking slogan
-
Diving,.taking underwater photos,tuna fishing,building, electrical work, solar ,Topside photos, gardening ,Nature,Outback camping. Travel . Lifes short
- Kelly in AK, Pres, Min and 2 others
-
5
-
My guess is the inside glaze is allowing it to leak (leaching) slowing thru the clay body.
-
Custar seems to be back in brown bags now ,at least from Laguna Clay Co.
-
I would check the burners and clean the orfices first as Neil suggests.
The kiln fiber board is cracked but not yet in bad shape.Except those massive opening arount the edges-you need to stuff thise with high temp fiber (loose stuffing) . At max temperature of 1300C for that kiln means the interior layer needs to be well above that to keep from cracking and coming apart. My guess is you have lost lots of heat thru thosew ceiling spaces around edges which also will cook the button wires holding this together very fast now, The idea is keep the button wires cool and away from hot face heat.
The lid has shrunk and the edges now have space exposed and you need to fix before firing again. That shows well in your photo of kiln ceiling.
That kiln is made of fiber board and I'm not a fan as it shrinks and cracks more than loose fiber unless its the very high temp stuff.
I would use material that rated to 1426C for all hot faces. For me thats 2,600 Fahrenheit. Fiber or soft Bricks As one who fires to cone 11 a lot it pays off in the long run.No spalling or excessive shrinking.
Mystery Glaze Defect! Help Please.
in Studio Operations and Making Work
Posted
Its just one of many things to rule out.