Black Spots Falling From Lid Into Glaze

[oldlady]

bad experience the firing before last.  found the items on the top shelf had various bits of black fired inside the glaze.  most awful was the long tray covered with bluegreen slip with the leaves done in clear.  great big black spot right in the center of the pot!  naturally, it was on one of the clear ginko leaves.  several smaller black blobs on other things as well.

 

last firing..............very carefully let the lid down after packing the kiln.  noticed black spots raining down onto the work and shelf.  removed each piece, blew the bits of black off and tried again.  took three tries before i finally was satisfied that no black spots were going to surprise me on opening the fired kiln.

 

after that firing, i looked carefully at my kiln lid.  yes, there is a crack, no wider than one of these letters   l    running sort of in a semi-circle below the center of the lid.  had just gotten an ad from L&L about their kilns and read that one of their special features is a "proprietary reflective brick coating that protects brick and minimizes dusting."  So i called to ask about it.  poor customer service person had no idea what i was talking about even after i read it from the catalog.  he was so bored with life in general that i practically had to beat him to take my order.  no, he did not know how much it was going to cost to send it.  no, they only use one shipper.  no, he had no info on how to use the stuff.  i was very sorry that i called.

 

the stuff came in a box about 4x4 inches, closed with 4 heavy copper staples.  had a hard time getting into the box.  inside was a plain white jar without a label.  nothing in the box but my invoice showing the name Facing Cement.  could not get the jar open, was it cemented closed???

 

called L&L.  long time waiting for someone who knew what this stuff is and how to use it.  told that i could not talk to anyone without my kiln model number.  lots of agony for nothing at all.

 

loaded the kiln today and just before closing the lid, i put a heavy plastic tablecloth on the top of the kiln and weighted it down so i could use the outdoor grass blower to clean and dust the lid bottom.  blew that thing so clean i could not believe it.  the black stuff was all over the plastic cloth when i finished and i carefully gathered it up and looked to see if i could identify it.  

 

the metal band holding the lid has been heated repeatedly over the years and it has dark fumed discoloration.  is it corroded? eroded? failed?  whatever the cause, the metal is flaking off and falling into the kiln as the lid flexes when i close it.  

 

anybody got a cure?   i am not about to call the L&L number again.  i HATE being treated like i am an idiot who just doesn't know anything.  "obviously there is something falling through the crack" was the suggestion.

[neilestrick]

Sorry you had a bad experience with L&L customer service. Were you talking to a tech or just whoever answered the phone? At just about any company, the person answering the phone won't necessarily know much about the products. They are there to take your order and process payments and paperwork. However, he should have put you through to a tech who could answer your questions. If you spoke with the tech, then there is definitely a customer service problem that should be addressed.

[neilestrick]

If the lid is cracked all the way through, you really should replace it. Nothing is going to keep it from flexing and shedding more crud into the kiln. Short of that your best option is to put another shelf at the very top of the load to protect the pots.

[oldlady]

neil, yes, I had to fight my way to a tech person who did not give me his name. yes, I know about using another shelf on top of everything. no, I do not have a large crack in the lid. I guess you did not notice that I tried to draw a hairline crack using the letter L. yes, I was on the phone for more than 40 minutes with absolutely nobody having any suggestions about what to do with the stuff in the jar other than thinning it and using a small roller. I still do not know what is really in the jar. I wanted the proprietary product used to seal the bricks. the jar has no label but the packing slip says it is facing cement.

 

the stuff is NOT brick dust, it is black metal dust.I am asking if there is any solution to the problem of the metal flaking off the band around the lid. do I have to buy a new lid??????

[Min]

Does L&L sell replacement bands?

[neilestrick]

Yes, you can just get a new band.

[PeterH]

I have absolutely no experience in this area. However this page from L&L's

website might be relevant.

 

Repairing a Cracked Ceramic Kiln Top or Bottom (Video)
http://www.hotkilns.com/repairing-cracked-ceramic-kiln-top-or-bottom

[Mark C.]

Oldlady 

This is a 16 year old Skutt that is rusty-I do not get any rust flakes-notice the high quality stainless steel used in construction-the handle and the bands are almost toast. Shutt=one big black spot

I am hoping L&L uses better stainless..

Mark

[Babs]

I get this in my old kiln .It is the metal from the lid coating coming thro' the cracked bricks. If not replacing lid or outer metal, only cure is to do as Neil says and place a shelf right up under the lid, uses up a bit of space but better than ruined platters.

I vacuum the under side of the lid and top edges of the kiln. These particles can be very fine but melt big!

IF ANd it is so, the front desk person cannot help, they should be educated to listen and pass on quickly to the correct person, unless it is a fobbing off technique which we can all  recognise and makes you move elsewhere. I no longer give my date of birth OldLady as one is then treated as a simpleton , well I try to hide that fact, but do not enjoy the patronising manner.

[oldlady]

mark, my kiln looks like it came from the showroom compared to your old one.  only the band around the top is discolored. and the fume trails above the peepholes.  what is funny is that the ancient, 1960 era, paragon next to my L&L has no discoloration on its lid band.

 

i realize that i did not spell it out, i assumed that all of you know i don't take a lot of nonsense from receptionists or anyone without any authority.  i worked for AT&T for nearly 25 years and know my way around a telephone.  i TAUGHT those people who annoy all of us with their sales calls.  don't think i did not try to get to someone with common sense.  maybe that person was on vacation.

 

the crack is the size of a human hair or a sewing thread.  it is not some gaping hole with room for odds and ends to fall through.  the black stuff is metal.  i proved that with my blower.  the kiln is cooling now and i was able to run a piece of kiln shelf along the CLOSED lid to knock off any protruding bits that might still be lightly hanging on.  got a tablespoon of rusted metal.  cleaned up the whole area.  keeping the kiln room clean is hard since it has a dirt floor but i realize that since i only use it about 15 days out of 365, it is dusty.  NO the stuff is not dust, it is metal flaking off the band.

 

now that i know about it, i can watch for the problem and prevent it from getting into my pots.  hope some of you will be alerted to watch for the same thing.  thank you all for your input, it helps to find the website info from peter and though i do not have a grand canyon crack, i know now how to find a cure for one. thanks  

[Mark C.]

Now I can think of you every annoying sales call that comes in?I hope thats not true.

Mark

[oldlady]

no, i only sold the technique of one business selling to other business clients.  someone evil decided to call ordinary people at dinner time.   and, doris hill, wherever you are, PLEASE pay your bills!!!

[neilestrick]

Take off the band and sand down the corroded area with some black sandpaper. It it looks like the integrity of metal is compromised by the corrosion (unlikely), then replace the band. You could rotate the band a little bit so that a clean area is above the vent holes. Often the corrosion is simply buildup of fumes on the surface, not so much the metal itself corroding. Is the kiln vented?

 

Photos?

 

Hairline cracks in lids are completely normal.

[Stephen Lewicki]

I can fully vouch for my wonderful and professional staff (who all have years of experience helping customers). They tried hard to help this person with the minimal information provided. Had she sent an email with pictures and the same description she put in this post she would have received a prompt comprehensive answer. She refused to provide her model number and serial number, which would very much help in answering her question. (All kiln lids are not made the same across models and across time). My staff was told that she didn’t have a computer and could not receive or send emails. L&L prides itself on its free and expert technical support. The more information we have up front the better job we can do.  Thanks to everyone on the Ceramic Arts discussion group and especially Neil who have chimed in. Stephen Lewicki, President, L&L Kiln Mfg., Inc.

[oldlady]

my computer was totally out of order.  and any member here can tell you how hard it is for me to post pictures.  i did not refuse to give a model or serial number, only said that the numbers were in the studio and the phone would not work that far away.  the numbers would not have changed the answer anyway.  yes, the lid is very complicated and just saying get a new band is a simple statement but the fact is that lid has a very heavy hinge that runs all the way from the top to the bottom of the kiln wall.  how am i supposed to get a new band installed?   

 

i know when i am being disrespected.  nobody listened to what i said, they just assumed i did not know what i was talking about and it showed.

[neilestrick]

If your kiln lives in a humid environment or isn't vented, then the fumes will definitely do a job on it. The band on my smaller kiln looks awful because my studio isn't air conditioned and the little bit of moisture that does escape from the lid has turned it a brown/green/yellow/white color by the lid handle.

 

I doubt that you need a new lid band. In 11 years of fixing kilns I've only ever had to do that once. But as I said before, you may need to clean it off if it's corroded on the inside of the band, and yes that's a job that will require unhooking the lid from the hinge and removing a bunch of screws to get the lid handle apart and band loosened up. It could also be that the screws are rusting out and causing the flakes. Or it could be something else entirely.

 

Ultimately, I am only guessing because I can't see the kiln, and that was L&L's issue, too. We can't give you definitive answer when we're just guessing. If they had the model and serial number, they would know how the lid was assembled and be more likely to pinpoint the problem. Specific models over the years have specific characteristics, just like cars, so yes, knowing the serial number could very well have affected their answer. The most difficult part of providing tech help is getting enough information from the customer to give an intelligent answer. When I help my customers I ask 10 time more questions than they ask me. I know you're frustrated, and I know you want a simple answer, but at this point we need more information. Do you have a phone that you can take pictures with and text them to me? If not, is there a neighbor that could do it for you? Photos would give me 90% of the information needed to provide you with a solution.

[flowerdry]

I must say,when a company President or any other high ranking company representative chimes in on a customer service issue and doesn't somewhere, somehow in his coresspondance express his regret for the customers negative experience, then I am NOT impressed.  Come on, Mr. Lewicki, you can do better than that.

[oldlady]

it does sound as though it is all my fault.  the computer was down.  I AM NOT COMPUTER LITERATE.  LITERATE, BUT NOT COMPUTER LITERATE.  i do not have a cell phone.  i live where cell phones DO NOT WORK!!  THERE IS NO CELL PHONE TOWER HERE.  I LIVE IN A VALLEY IN WEST VIRGINIA.  

 

i know it is hard to believe that in 2015 America there are places that are not urban and where cell phones do not work but if there is another one of those TV commercials showing the extent of cell phone service, notice the big, blank areas.   i live in one of them.

 

 

I have taken pictures of the lid but the pots were tossed and are gone to the dump.   i took the pictures to a kiln repair center and discussed the problem.  i still have a jar of stuff without a name and without directions for use.  it is not what i need for this problem but i will keep it for someone else or for some day it might be needed.  peter sent me more info than anyone at L&L even considered giving me.  now that the computer works again, i can watch how to repair a huge crack that i DO NOT HAVE.

 

neil, i really do appreciate your concern. you have always been clear with your help and generous with everyone who asks a kiln question. i wish you could grant me the courtesy of believing that the issue is not that i was unreasonable and so nobody could help me.  i am not just some dumb woman who does not know what is happening because i am old.  that is the way each of those employees approached me. 

 

i think it is a general lack of empathy with someone different.  how could someone really say that dust is falling through the crack in my kiln lid when i said it was a hairline crack and the falling stuff is metal?  how does knowing that my model number is e23T-3-240, serial 070703-A help?  is someone going to say my kiln is OLD so i should expect this to happen?  

 

i have cleaned off everything that could be scraped from the metal.  it still remains that the thin metal band is THIN while the Paragon from 1960 has a T H I C K metal band.  why would someone build a great kiln with all kinds of great features and then put this flimsy metal in a place that gets fumes and heat repeatedly?  yes, it is humid here.  no, i cannot afford a kiln vent system.

 

 the heavy hinge makes it impossible for me to do anything with it by myself. i will simply be aware that it is scraped before every firing and watch that nothing falls into the work as the lid is lowered.  

 

mr, lewicki, do you still say in your ads that anyone can replace the elements with just a screwdriver and a wrench?   that mistake should have proved that you are not always right.  none of us is.  

 

for anyone else reading this, sorry,  but if you are new to having a kiln, now you know what to look at if you see black spots in your glaze.

[Jennifer5555]

Thanks to those who posted useful information which was very timely for me.   Out of the clear blue we have started to get black spots too, on a relatively new Skutt.   What is particularly useful is the information about humidity.   Our kiln was moved from NV to the Gulf Coast so the humidity concern may explain our black spot phenomena.

[neilestrick]

I seems to me that what we have here is frustration on both sides. L&L is frustrated that they can't get photos, and Oldlady is frustrated that she didn't get a solution. IMO, I don't think anyone is to blame; it's just an unfortunate situation. This happens more often than I'd like to admit when it comes to technical support. I've been there myself, on both sides, and it's no fun for anyone.

 

Oldlady, I did not mean to say that you are being unreasonable, and I apologize if it sounded like that. This is simply a situation where we are not able to help you simply because we don't have the information needed to make a diagnosis. Sometimes, like in this situation, we have to actually see the kiln, or even see it in person. Without that we are just guessing, and wasting your time chasing solutions that won't help. That's not your fault, or lack of willingness, it's just the way it is.

 

Regarding the kiln itself, here's what I know:

The sad fact is that sheet metal costs are considerably higher than they were 30 years ago. Kiln companies use the best materials they can afford to use. This issue comes up regularly here on the forum, whether in regard to sheet metal or thermocouples or screws or whatever. If they built the 'perfect' kiln, no one would be able to afford it. If we had that kind of money we'd all have front loaders.

 

Kilns get all sorts of corrosion on them, and most of the time it's just on the surface and does no real harm to the metal. They only stay pretty for a short while. Screws will rust out to the point that they have no threads on them. There's a lot of water vapor and corrosive materials in the fumes that come out of the kiln.

 

Kilns require work over time. Unfortunately (but fortunately for repair guys like me), not everyone can work on their kiln, and a call to the local repair person is occasionally needed. Certain jobs are a real pain, others are simple. Yes, L&L elements can be changed with just a screwdriver and a wrench (I do it all the time), unless you've fired your elements to the point that they are a slumped over mess, in which case a pair of needle nose pliers will be helpful. But there are no element pins or crimp connections in an L&L, and that's their point- element pins and crimp connections are a pain to deal with, and make element changes take a lot longer than they should.

 

Every brand of kiln has it's benefits and faults. There is no perfect kiln, and no matter how well a kiln is built it will need repairs at some point, and there are some issues like corrosion that are unavoidable. Sometimes there are simple solutions, and sometimes not. I personally took more than two weeks to solve a very strange problem with a customer's kiln a few years ago. None of the other techs had ever seen the problem before, and L&L made a change to their kilns to prevent it from happening again. I do always do my best, but sometimes it's really difficult to find the solution.

[Stephen Lewicki]

To all of you who have been following this thread and are concerned about corrosion I thought I would copy and past this from our website:

 

Why does my kiln corrode so quickly?

A: 

Corrosion on a kiln is perfectly normal... mostly because it is a kiln! Hot-to-cold-to-hot environments, plus all the water vapor, not to mention sulfur, fluorine, carbon etc. coming out of the clay all work to create a very corrosive environment for metal.

Corrosion In Different Materials

1. Corrosion to untreated steel will happen overnight, even when it is not part of a kiln.
2. Corrosion to galvanized or aluminized steel- like chimney flashing, or like your kiln's stand, won't happen as quickly, but it will happen.
3. Stainless steel, like the kiln casing, is better- it can take many years to rust it, but it will blacken or potmark rather quickly near the heat.
4. On a kiln everything discolors and corrodes pretty quickly. How soon this happens will depend entirely on several factors.
5. The #1 reason why kilns corrode is for lack of down-draft ventilation. We highly recomment installing a down-draft type
   vent (the Vent-Sure) to get the corrosive fumes out of the kiln. A room vent and/or a hood vent does not extract the corrosive fumes from the kiln itself.
6. The #2 reason why a kiln rusts is a lack of ventilation for the kiln room. If the room gets hotter when you fire, then there is a build-up of moisture rich corrosive air surrounding the kiln.

L&L's Kiln Vent

Using a downdraft kiln vent like L&L's Vent-Sure will minimize fumes and water vapor coming in contact with your kiln's outside. Using a good room venting system designed and sized by an HVAC engineer will keep any other corrosion to a minimum.

Materials

1. If you are making your own clay you may have a higher concentration of the minerals that cause acids to be be created in the hot moist environment of the kiln.
2. If you are seeing excess corrosion and your have a down-draft vent that is working properly then the next area to examine is the clay that you use. Check with your clay supplier.

Environment

1. If the kiln is kept outside (some people in warm relatively dry climates do this) remember that dew can form on the kiln cse in the morning and this can lead to corrosion.
2. Also people who live near the ocean can experience higher than normal rates of corrosion form the salt in the air. The best protection for this is the keep a kiln inside.

PS to everyone - thank you Neil for being so helpful. It would be much appreciated by all if the discourse on this forum can stay civil. I regret that OldLady had so much trouble getting the information she needed but I do hope the readers can understand that manufactures need as much information as possible to help customers. It is often hard to remember that when one is frustrated, as OldLady clearly has been, that people really are and really were trying to help them. Some of the questions may seem pointless (like asking for model number and serial number) but considering we have made kilns since 1945 with lots of models and types of constructions I really hope everyone can understand how that matters. The advice we give for one kiln is not the same necessarily as it would be for another one. For whatever it is worth we will be including our full brick repair instructions with any facing or cement that we send out.

[Rae Reich]

Dear Old Lady,

Thought I'd message privately with commiseration and encouragement, but changed my mind. The age and gender bias seems to be virtually indiscernible to those who hold it. I experienced something so similar this week that the frustration is still fresh. I especially love being fobbed off with a simplistic answer repeated verbatim, slightly louder. Hmmmm, yes, metal corrodes with humidity.

 

The hairline crack was a red herring for admitting metal flakes, but could indicate excessive flex in the lid that would exacerbate the flaking. Could the lid be stiffened across the top somehow so it doesn't flex (do you know a welder?)? Also, I wonder how successful your vacuuming was for the next firing? If flakes are still wandering in, could you contrive a "gasket" of sorts, maybe of a thin layer of fiber blanket? The top edge of the kiln could have abraded enough over the years to let bits of the metal lid rim sift through. If the edge is abraded enough to have gaps, maybe the mystery white stuff* could be troweled on to make it straight again?

 

I believe this is the sort of brainstorming you had hoped to elicit.

Rae

 

*When L&L sends you the instructions and, hopefully, an apology for the misunderstanding.

[oldlady]

thank you, Rae, the problem is endemic.  our popular culture tells everyone that old people are silly, out of touch and can be dismissed.

 

 i just hope the well-trained and experienced employees of L&L have now learned that black bits of stuff falling into the kiln while the lid is being closed is from the exterior metal band.  since the band is around nearly all of the kilns, no matter what model number, maybe they will not insist that before i could talk to a tech person i  M U S T provide a model number.  i did not refuse, just explained that the number was in the studio kiln room and my phone would not work that far away.  i knew that if i put the phone down long enough to get the number that the person waiting would hang up because there was nobody on my end.

 

in addition, i was told that i M U S T send an email to get an answer from someone with technical knowledge.  not a picture yet, that came later after i said my computer was down.  it was off all that day and returned to service in the night.  

 

i used the word "flex" which must have made the person picture a wildly, waving piece of rubbery stuff.  not so.  the lid has a piece of metal that runs all the way actoss the top from the handle to the hinge.  i simply meant that the normal movement when the lid is in the process of being closed.

 

my original thought was that something black must be coming from the lid itself.  so i called to ask about what could be done.  the person i got had no idea.  i asked specifically about the proprietary "paint" that their many page brochure mentioned.  the young man sounded asleep, confused and unable to give me any information about that product.  i read it to him and he still did not know anything about it.  still thinking it must be something on the underside of the lid, i ordered the stuff. he did not know if it was a liquid or a powder to which i would add water.  he could tell me the price for the product but not my shipping charges.  that was the first call.

 

once the box arrived and i found the jar without a label inside, i finally got it open to find a thick paste.  so i checked the kiln lid and found the flaking metal band.  realized that was the problem.  the second call is where i was told that if i had a crack in the lid then dust was falling through that crack (HAIRLINE!) and i could not talk to a tech person without a model number.  the person who was finally found just repeated that silly statement and i gave up.  yes, i was frustrated.  yes, i will always have the reputation as the frustrated old lady who would not LET anyone help her.  and all those employees will be smug in their sure knowledge that i was just an old lady who does not understand.

 

 

L&L kilns are the best and i believe that even now.  if anyone will read the directions that ordinary people are sent with the new elements that are advertised as being replacable with only a screwdriver and a "wrench" he will find that you also need a multimeter, not just any kind but a digital one and you will need several other things never mentioned in the ads.  in addition, you will need to replace all of the stainless steel  screws holding the control box with fatter ones so the box will stay attached,   i did it, took 3 days and several trips to various stores but my elements are in place and beautiful even now.

 

i cannot work on the band any more because it is now about the thickness of a doubled over piece of aluminum foil.  i will scrape the edges every time i use the kiln and watch as the lid closes to prevent the black bits from falling into my glaze. eventually i will get over the feeling of being betrayed.

[Rae Reich]

Well, if you're sure the black bits are falling as you close the lid, how about waxing the ragged edge before closing to temporarily "glue in" the bits. The wax would burn off, of course, and have to be redone with each firing.

 

This would be less wear on your raggedy band, as regular scraping will surely dislodge more stuff and wear it down more.