Hulk

I’m happy to say that after a couple of decades in clay, having built several  kilns and operated many more, I finally graduated into the class of “Has Successfully Replaced Elements” a couple weeks ago (I completed the “empty kiln to 04/oxidize the elements” firing, but still have to complete the final, “cone 6 glaze fire.” So, I haven’t actually gotten my diploma yet, but am confident.). 
I have earned many other (self-awarded) certificates over the years. “Scraping Shelves,” “Proper Application of Kiln Wash,” and “The Economy of Angle Grinders,” were earned concurrently over time. “Low Fire Clay in a High Firing” was a crash course. There’s a lot more fuel kiln stuff rattling around in my head than electric. 
I feel like most of what I’ve learned about kiln maintenance, operation, and repair has been so incremental it’s hard to place myself on a scale. The thermocouple goes out and you learn how to replace it, you don’t have to learn that now. Multiply that by kiln-life experiences and you wind up knowing a lot that most people don’t. We end up being experts by just making things work day after day, year after year. 

I appreciate the info that L&L has good customer service.   I haven't had mine for a year yet,  I only have 15 firings on it.   I use my other smaller kilns more because I can't wait to fill the L&L.  At my age I don't think I am going to get better at waiting.   Denice

Good question.  I have 1000 firings on my L&L.  My husband and I work together on it,  Mostly I could do it myself, replacing elements, thermocouples, wiring etc.  But it is nice to have the help.  We have even replaced bricks (yes, the one on the bottom ring).  And patched bricks.  I helped a friend replace bricks and elements on a larger, older L&L.  But I have never attempted repair on other brands.  Not sure if there would be a lot of difference or not.  We are hours away from any sort of help, so we had to do this on our own.  L&L has GREAT over the phone, email, support.  My hat is off to Rob Battey.  He patiently listens to my kiln problems and gives such down to earth sensible advice. Over the phone, and via email.  I really appreciate L&L. They have made it possible for me to keep my kiln running.  

When it comes to kilns (and I assume this is an electric only thread) I do it all myself. I have a manual electric skutt (no computer) I added a fire rite control that turns it up as fast or slow as I need. I do not fire this much anymore as most pots are bisqued in my gas kilns. I have rebuilt a few of these type of kilns. pretty easy stuff. Same with shelves I do all the maintenance . I never fire over bisque temps in my 10 cubic skutt.I have upgraded to better connectors (not crimps) and leave all switches on high (the fire rite turns the kiln on and off) I did replace some of the jacket a few years ago and have more jackets in a box but have yet to finish the job..I think I fired this once last year.Its cone sitter kiln for turn off with a safety timer.I did repaint all the contol boxes a  non skutt color when the red color flaked off with rust. I have upgraded to real stainless screws as well so they do not rust. Any time I work on it I make it better with better materials when I can. Thees manuel kilns are pretty bullet proof and go for a long time without trouble.I have had 3 skits over time (all used) and if I bought new one it would be an L&L.
I would hope L&L used better stainless screws and parts. My beef with electric kiln companies is they skimp on quaility on small parts to save a few bucks. The stands are to small and the controls get to hot from lack of space and insulation. The stainless can be of poor quaility as well and rust.Not sure if any manufacture has it all figurted out. I do like the hard element holders  of top brands as well this feature alone is worth it in my view as the bricks break out every element change if there is not hard holder.

I am pretty good at maintaining the shelves, stilts and vacuuming out the kilns.   I use to have my kiln repaired for me by the local ceramic  supply store,   now that my husband has retire he has taken over that job.  Now that I think about he didn't start encouraging me to buy new kilns until he took over the kiln technician job.   Hmmm    I probably could of done it but I have a problem dealing with electricity.    My dad had our house wire badly,  you could get suddenly shocked anywhere anytime.  One time I got a bad shock washing dishes.  When I was young the fire department would  safety check houses in the neighborhood.   My dad would make us hide and not open the door.    Denice

Hi folks, another kiln question.  Over the years I have done a lot of maintenance and repair of kilns in the school district I worked at, and at home. I would say the first level of maintenance is keeping the kiln clean. Using small dust brooms and dustpans is a good beginning place to remove all of the bits that occur during firings. Then there is a first level of repair, replacing bricks, floors, etc. On the stacking kilns much of this is easier than on the solid box kiln that used to be the norm years ago. Then there is entering into repair where you replace elements. This can be scary at first, but following simple steps and manuals can really make it much less of a job than you think, especially if you are handy with tools. This to me is the repairer level where most work occurs. Then you come to repairs where you replace insulators, wiring harnesses and other the setter, or today the controller. I would do all of that but the controller. 
QotW: When it comes to kiln maintenance/repair, how do you rate yourself?
best,
Pres

There is some conflicting information about the first firing floating around, both from different kiln manufacturers, for different purposes, and even within the same manufacturer's instructions. L&L's printed manual has long instructed owners of their new kiln to do an initial break-in firing of the empty kiln (but with the furniture) slow bisque to cone 5 (yes, five, not oh-five) with a 3 hour preheat for the dual purpose of seasoning the elements to develop a protective oxide coating and to set the cement used during manufacturing to hold the kiln bricks together. Their newest manual indicates these instructions are for both the Dynatrol and Genesis controllers.
Conventional wisdom by some other kiln manufacturers instruct owners of their new kilns to do the initial firing slow to 04. This is consistent with the recommendation from the manufacturer of the Kanthal elements for seasoning newly installed replacement elements, again to develop a protective oxide coating on the wire. Out on the interwebs, many commenters who own these other brands of kiln will adamantly (but incorrectly) assert that new owners of all brands of kilns should do the initial firing to 04.
And now we have this new video from L&L for programming the first firing on a Genesis controller that instructs a glaze firing to 04 with a 1 hour preheat. However, if one looks around on the L&L website, there is another video for programming the older Dynatrol controller for the first firing that is consistent with the printed instructions, i.e., slow bisque to 5. Is the basic kiln constructed differently for a Genesis vs. Dynatrol controller that it would need a different initial firing? I don't work there, so don't take my word for it, but the conflict seems fishy to me. With 3 instruction sources to choose from (the printed manual and 2 videos), I would go with the 2 that are consistent, i.e, the printed manual and the Dynatrol video. But maybe that's just because I am a recovering accountant...

i had entirely planned to use hard brick for this, but you are correct I could definitely foresee the potential for warping on a 1" split even with the hard bricks, as well as the potential for cracking at the slots either below or on the end wall joints due to one uneven heating of the split surface. 
i have not had a chance to research here yet but will definitely do so today, as the idea of a single powered burner is a possibility i didnt really consider.
in my second post i mentioned that off the top of my head i said a single 200k burner should be sufficient. i used this data to get my number.  If you have a soft brick kiln with 9" walls, you'll need: 6,000 - 10,000 BTU/CF for cone 06, 8,000 - 13,000 BTU/CF for cone 6, and 10,000 - 16,000 BTU/CF for cone 10. i then took the high end of 16000 and multiplied by 8.3 for the cubic foot inside the chamber which gives me 133k roughly. i added some additional being as the lining is 8.5 inches but has approx 3/4 inch cutouts on most walls and floors. however i had thought using 2 lower rated burners but stills added together went well above my needed range should allow the kiln to work without having to run at full tilt.
the things i seem to be having the most trouble finding out are the draft requirements, as i am not sure how the airflow really works inside of a kiln like this. you have both given me things to consider and later i will take some time and create a new drawing based on the ideas given to me to hopefully be critiqued and pointed in the right direction. 
this is the reason i came here, to get the advice of those more knowledgeable than me, so thank you again.
matt

I can't claim credit for the recycling rubber idea.  I got it from the Tiki Technical videos where he's using Rebound 40 which costs about twice as much as the Mold Max 40 I'm using.  But he's also doing MUCH higher production numbers on his mugs than I do with my equine editions.  
I don't bother with a spread sheet for simple math I can do in a couple of minutes, though people can!  But I am a big fan of using spread sheets for more complicated tracking.  Like for every edition I release I use spread sheets to track what's been cast and what # of the edition I'm on, how many I am getting out of a mold and which mold # I'm on, when a piece has been cleaned, fired, packed, shipping paid or pending,  shipping labels made or not, client name & address for orders, what/how/when they paid their deposit, any monthly payments they are making, special directions for alternate shipping destinations -like if they are in Germany, I'm not set up to ship there so pieces get sent to an intermediary who can forward them on for the client, my total costs per piece, special requests by clients are noted and separate pages set up for those if needed, and so forth.  I suppose I could add the math parts to my already existing note sections just to track it.
Running my LLC is a lot of work so there is a lot to track including taxes, quarterly payments, property tax, etc.  Also lots of notes on the usual stuff like testing new glazes, mixing or overlaying of various brands of over glazes like combining enamels with china paints, how glazes change the look of various underglazes, notes on new slip batches I've made, whatever.  As I get older and my memory less reliable I am having to go back and check my notes more often.  Like to remind myself ... mixing cadmium based overglazes with non-cadmium colors is not a good idea!  
 

Spreadsheet maybe?
I use one for updating my Wordle average each day, another for the running list of used words.
...another for bike miles and bike related metrics.
Another for bookkeeping, with a page/tab for each category.
Several with pottery related stuff. 
They can be handy for repetitive maths.
I'd learned to appreciate Excel through work - so handy for analysis (protocol, messaging, transcription...) as well as repeat stuff (students' grades, energy calcs...)
I like the recycle idea!
We've thrown rocks and cement chunks into fence post holes to save on concrete...

Tiny tips one may have never seen, read, or heard 'bout before.
Flexible metal rib, ideal (almost) for moving insects on the surface of water/glaze/liquid to outside the Studio.
Tiny spiders, gnats, et cetera land on the surface tension - timely removal can prevent a tiny insectoid blob (and the bug can live on!). The rib's edge, just on the surface, allows the bug to change footing without wetting, nor harming them. Step outside, blow the bug gently off the rib, onto a rock, plant, or somewhat. Note the tiny antennae nod of thanks.
Using actual real chamois leather chamois*?
Is it floppy - stretched out - slimy and soft? When next you pour hot water into your throwing bucket, note that your chamois, when exposed to hot water, will shrink and "tighten up" considerably! ...maybe too tight? Don't worry, it will loosen up after while...
It's not rainy today!

*We have an actual leather chamois that was a gift promotion from an auto parts store, decades ago.
I've been trimming strips off of it for pottery use over the last six+ years...

Another thing that works for rims instead of a piece of chamois is the microfibre cleaning cloth that comes with eye glasses. They last a long time and don't go slimy at all.
Wire coat hanger corners to make callipers. 
 
 

Now lastly for a bit of math.  Yes, MATH.  But this is real simple stuff so no groaning!  If I have six small molds I have clayed up and boxed, I need to know how much plaster to mix up to pour them all start to finish with all of their various parts.  Or rubber!  Rubber is especially expensive, running about $100 to $250 PER GALLON depending on the kind of rubber I'm using.  In this case I'm going with Smooth-On.com's Mold Max 40 (the number is the shore hardness).  These are for my masters, including all mold parts and the positives for making plaster production molds from as well.  So by the time I'm done there will be no hollow parts.  Most people can deduct a little bit based on your rough measurements of hollow cavities you won't be filling.
So, how much do I need and how do I figure it out?  Now I have set up all my mold boxes and clayed up for my first pours I have a pretty good idea how large each finished mold will turn out to be.  So they are roughly the following in inches:  4x4x6, 3x4x4, 3x6x7, 4x6x1, 3x6x2, and 2x2x4.  These are to produce one mini horse sculpture with parts to assemble, as well as my flat medallion sculpted above, and another larger medallion I'm molding of another artist's work whom I've purchased ceramic casting rights from.  I know I just need enough rubber to fill in approximately this much space per each mold and I can pour plaster for extra outer supports to conserve on the amount of rubber I need.  If I multiply the three measurements for each approximated mold I get totals like 96 for the first one, 48 for the second one, 126, 24, 36, and 16 which I then add up to get a total of 346.
What does that mean?  It means that my total volume I plan to fill with rubber (or plaster) is roughly 346 cubic inches.  Then I go pull up a handy converter online doing an internet search with the keywords 'cubic inches to gallons converter' and presto!  Up it pops. (I use online converters all the time for mm to inches, oz to grams, whatever).  Turns out that 346 cubic inches equals just a hair less than 1.5 gallons in liquid.  Yay!   This kind of information can tell me about how about much plaster I will end up using for making all six molds, AND also tell me how much rubber because I'm making the rubber masters for plaster mold production.  Therefor since my choices are ordering the rubber in pints, gallons, or 5 gallon sizes, I'll order 2 gallons.  I'll possibly end up with a bit more than I actually need but that's way better than cutting it too close and not having enough to pour all six.  For plaster your voids may be large enough to measure, multiply, then deduct from your total volume.
Other tips - while this won't help with pouring your plaster molds, you can cut up old rubber molds and use them to help fill in larger volume areas during your pour.  This can also keep your rubber cost down.  So if I cut up a few molds into little cubes I can toss that into a 5 gallon bucket until I'm ready to pour my rubber.  Ahead of time I can figure out about how much of the recycled rubber I'll be using and then I can downsize my order perhaps to only 1 gallon instead of 2!  That could save me anywhere from $100 to $250 per gallon I don't have to order in rubber!  Mold Max 40 runs $114 per gallon plus shipping so it's not nearly as costly as some rubbers.
I eyeball my left over pottery plaster.  I have plenty to mix up a couple of gallons of plaster but with the expectation that I'll have some wastage every time I mix, it may be cutting it close.  Besides, I'll be wanting to pour multiple production  molds of each project anyway.  So to be safe I'll pick up another bag of plaster too.
See?  Simple, basic math.  It can be so  helpful!   

Small update - here is the finished oil clay with a very simple Lego mold box erected around it.  I tend to use Legos (or generic off brand) for tiny things and I made larger mold boxes out of wood or thick acrylic plexi as needed for larger projects.   I have sealed this down with oil wax and then added a bead of oil clay all the way around it on the outside.  I'm about to add a very thin bead of oil clay around the inner edge of the box as well so I can be REALLY sure there will be no leakage.  I will then coat the inside of the mold box and glass backing with oil soap.  I can fill it with water to the depth I want to check for leaks, then pour the water off and measure it to see how much plaster or rubber I will need to make my pour.  
At this point you can see I haven't bothered to lay in a pour hole, sprues for air venting, or even mold keys - but I can!   I'd just want a larger mold box to give me plenty of space to do that, which I have not set up  here.  This pour is set up for a uber simple one sided open mold.  It is otherwise about ready to pour plaster or rubber.   If I did this in plaster I'd want to make a rubber mold of my plaster mold before I started production so I can pour however additional plaster molds I might want or need in the future. 
Another option is I can pour rubber now and skip the plaster.  I can still use an open backed one sided rubber mold to cast a single flat resin.  I pull that out, clean it up and fine tune anything I like, even adding more sculpting in epoxy if needed.   I can get away with undercuts and very thin areas if it's going to be rubber molded for resin production.   I can also cast  a rubber positive master from that rubber mold, from which I can also go on to make plaster production molds.  So there are LOTS options on how to proceed! 
In my case I want to do BOTH so I have to decide which one I'm going to do first, then go from there. 
 
  
 
 

Tiny tips one may have never seen, read, or heard 'bout before.
Flexible metal rib, ideal (almost) for moving insects on the surface of water/glaze/liquid to outside the Studio.
Tiny spiders, gnats, et cetera land on the surface tension - timely removal can prevent a tiny insectoid blob (and the bug can live on!). The rib's edge, just on the surface, allows the bug to change footing without wetting, nor harming them. Step outside, blow the bug gently off the rib, onto a rock, plant, or somewhat. Note the tiny antennae nod of thanks.
Using actual real chamois leather chamois*?
Is it floppy - stretched out - slimy and soft? When next you pour hot water into your throwing bucket, note that your chamois, when exposed to hot water, will shrink and "tighten up" considerably! ...maybe too tight? Don't worry, it will loosen up after while...
It's not rainy today!

*We have an actual leather chamois that was a gift promotion from an auto parts store, decades ago.
I've been trimming strips off of it for pottery use over the last six+ years...

Perhaps Per B Sundberg, per image search
Per B Sundberg | Objekt med hål (2013), Available for Sale | Artsy | Ceramic art, Pottery sculpture, Sculpture art (pinterest.com)

Double check that chromite!
...to be sure, what, exactly, is it?
More to the point, is it a stable and fairly safe material?
Is it a somewhat toxic material?
Is it a highly toxic material?
If there's any interest in mixing glazes, keep'm!

Thank you everyone for the info you have given me.  Who knew that someone in the UK would know Richler Pass?  But as we are in BC that is a good probability.  All this information is very useful and will help us sort out what we should keep and what goes.
Yes we make our own glazes but as a group and individual members do not have access to these chemicals.  I suspect we will want to get rid of anything that is Toxic.  Unwanted chemicals will be offered to members who do make their own glazes in their own studios and then to other organizations which have pottery classes.
Thank you so much,
Lin

I would keep the kaolins, can sub those quite easily in glaze recipes. Calcined kaolin I would keep, use it as part of the kaolin in any glazes that crawl due to high kaolin amounts.  (have to recalc the amount used to sub for un-calcined kaolin) 
Alumina oxide can be used in place of alumina hydrate in kiln wash (use 1/3 less by weight).
If anyone uses washes then the Barnard, Burnt Sienna and Umber can be used in those if they want dark/earthy colours.
Kona (F4) can be subbed for Minspar 200 in a 1:1 ratio.
Tennessee Ball comes in different forms, given how inexpensive ball clay is I would donate that one if you don't know which you have. Fireclay, Sagger clay and mullite, unless someone is making their own bodies I'ld donate those. Redart can be used in bodies and glazes.
Silica sand, might be useful if someone is firing large heavy pieces or wants to wedge into their clay but if nobodies used it for years maybe not worth keeping.
CMC gum, mostly used for making brushing glazes or hardening a dusty glaze.
Calcium Carb precipitated, this is just whiting/calcium carb, keep it. 
Black Iron Oxide, can be used in glazes, need to compare the iron content with whichever red iron oxide you are using to sub it. It doesn't create the red staining mess that red iron oxide does.
 

Min:   your suggested firing schedule resulted in an improvement.  I now have two without pinholes or dimples; one with pinholes; and the rest with dimples.  Thank you.   
# 1 Original firing schedule where the Variegated Blue              # 2  Firing schedule where the refire and studio white had no defects
and Rutile Green had no defects but the rest did was:                             ^5 SS bent to shelf; ^6 slight bend.  = 5.5
100.     220.     30                                                                                                     100     220.     30
350.     2000.    0                                                                                                       350    2000.    0
108.     2190.     5                                                                                                       108    2165.    18
9999.   2090.    10                                                                                                   9999.  2085.    12                       
500.      1900.     10                                                                                                  500.     1900.    10
125.       1400.      0                                                                                                   125.      1400.    off
The results of the glazes for Firing # 2 on 1 lb. bowls were:
Wollastonite Clear -- 1 pinhole outside 3 on rim
Studio White -- no defects
Folk Art White -- dimples
Variegated Blue -- dimples
Rutile Green -- dimples
Refire -- no defects
Test Glaze on test tile -- four pinholes on side next to element.  
I also fired a commericial glaze (Amaco HF-9) at cone 5 + 5 minutes but it had dimples and one large pinhole (^5 bent to shelf).  Two potters on instagram fire this clay at 5+ and seem to have good results with commercial glazes.  One uses Amaco Honey Flux (which is a fluid glaze).  Amaco says some of their glazes shiver on this clay.  
I welcome all suggestions that might result in a defect free firing schedule for this clay.  
Neil:  I will try your suggestions on shortening the bisque schedule in my next endeavour.  Right now I have over a 100 pieces bisqued using the schedule I outlined above, so will concentrate on the glaze firing schedule with the already bisqued pieces.  
Peter:  I don't think it is the wollastonite in the glaze that is the problem (one of the glazes has Wollastonite and the other Whiting), however there may be Wollastonite in the body.  I sieved the clay slurry and did find some small white chunks in it that didn't go through the sieve.  They may be silica or feldspar??  Photo attached.   On one of the bowls that I glazed in a commercial clear, there was a white chunk on the outside, under the glaze that was the same as the one on the screen.  
Bill:  Hopefully the problem will be solved with the firing schedule, so I won't have to change the glaze fluidity (not my strength).  I'm thinking your suggestion of multiple holds may be part of the solution.  
Hulk:  Thanks for your suggestions.  I still hope to find a solution without changing the clay.  
 
 

On very little evidence this might be a grass-ash (rather than a wood-ash).
South Okanagan Grasslands Protected Area
https://bcparks.ca/south-okanagan-grasslands-protected-area/
The Richter Pass has long been a priority for conservation efforts in the Okanagan. The primary role of the South Okanagan Grasslands Protected Area is to protect the dry grasslands and open forests that represent one of the four most endangered ecosystems in Canada.
Glazy has some lawn-ash analyses at https://glazy.org/materials/15037
The materials section at glazy might complement digitalfire's coverage
https://glazy.org/materials?primitive=1
Digitalfire also has
Those Unlabelled Bags and Buckets
https://digitalfire.com/article/those+unlabelled+bags+and+buckets

DigitalFire can tell you about the usage of most of those. https://digitalfire.com/material/list

Neil mentioned that "A lot of people also put a shelf at the top, like 3 inches below the flue opening."
Rae said "A Soft brick damper is easier to slide, but can drop debris onto pots on the top shelf (speaking from experience). Keep top of kiln as clean as possible. "
Both are good points.  I just thought I'd add a fancy drawing to illustrate what Neal described. The top shelf is reported to keep some of the heat in the kiln better but still allow the right air flow. It should also address Rae's point about debris. I don't know from personal experience since my gas kiln is a downdraft, but it makes sense to me. In your test firings, how much space is between the kiln shelves and the sides of the kiln?

Gas combustion made simple! At about 10:1 air / fuel you will get a nice blue efficient flame (natural gas, propane not so much), plenty of oxygen for efficient combustion. A nice blue base of the flame is a reasonable indication of an oxidizing fairly efficient flame so the answer to your question is basically yes it’s a decent indication enough primary air is coming in. . Venturi burners are sort of self calibrated within a pressure range of operation so the more gas pressure, the more primary air is sucked in by the Venturi effect. Your burners do not appear to have a primary air shutter and that is ok really. A nice blue color, devoid of yellow indicates you are operating within a reasonable efficient pressure  range for this burner.  
About 50%:of the air for combustion comes from the primary air and 50% secondary air. The secondary air enters around the burner or the hole in the bottom of the kiln where the burner penetrates.
when closing the damper there will be an absolute best position for a given gas pressure where you are losing the least amount of heat but still allowing enough secondary airflow through the kiln for all the gas to be burned efficiently. Close it more and flame efficiency drops, less secondary air comes in the holes around the burners.
Folks often set their gas pressure -  then find the point where performance begins to drop and open their dampers slightly more from there to get near that perfect balance. Every increase in pressure generally requires a slight opening of the damper so patience is key until you learn about where the damper needs to be for a given pressure for your kiln.
Your stuff seems to be working as designed, I would’ suggest testing with a damper first, it seems you are close ……. before making changes to the original design. Meaningful fine tuning  damper adjustments start about 1000 degrees btw.
There always seems to be a lot of confusion with combustion
Simple Bunsen burner pic below we use to teach primary and secondary air and a fuel air chart showing efficient mixtures you might find helpful.

SOLD!!! For Sale, New York City. Used (but needs repair)  Baily Electric Slab Roller with Long Table (DRD 40 Electric Slab Roller w/Long Table (baileypottery.com)). The rod that connects the two ends of the mechanism is bent and has to be straightened. Otherwise, the slab roller is a heavy-duty, easy-to-use, marvelous piece of equipment which Baily is currently selling new for $4700. If you can fix it, you have a deal at $500.