Disaster!
Well, perhaps I exaggerate a bit – there were no tornadoes or tsunamis, no fires or floods, no permanent damage to self or property, so really, I am quite fortunate. But, when both your production kilns decide to break at the same time (mere days before an important show), ruining numerous ceramic pieces that had been months in the making, it’s more than a bit of bad luck. Needless to say, I was more than a little upset having lost a couple hundred hours of work and the focus of my exhibit for the upcoming show, but what can you do? These things happen. So, after cursing my kilns, I rethought my exhibit, used some of my older pieces, and actually did fairly well at the show. After the show, I ventured back into the kiln room to attempt to figure out why my kilns had betrayed me.
Ah, my babies! What can be ailing you! My original kiln, the old and wonderful manual L&L Econokiln, was easy enough to diagnose. The top element had burned out (probably due to some sort of contamination falling onto the element during the firing). There was a broken section in the element, and part of the element had fused to element holder. However, my second kiln, my programmable Blue Diamond kiln, is still a mystery – I have no idea what is wrong with it.
I am always nervous about going into a kiln and poking around. So, over the past years, I have spent a significant amount of money on professional kiln repair. However, this time I decided that the Econokiln repair would be simple enough to do on my own, and after all, as a ceramic artist, I should be able to repair my kilns on my own!
I am always nervous about going into a kiln and poking around. So, over the past years, I have spent a significant amount of money on professional kiln repair. However, this time I decided that the Econokiln repair would be simple enough to do on my own, and after all, as a ceramic artist, I should be able to repair my kilns on my own!
Project:
Replace a Kiln Element
Tip: Before making any repairs on the kiln, make sure the kiln is unplugged or disconnected from the power source.
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Materials
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Various tools used to replace the kiln element: wire cutter, flat nose pliers, needle nose pliers, screw driver, nut driver and combination wrench
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Where to begin? Well, that’s not really too difficult as the job was easily divided into four segments:
- Remove the old element
- Remove the damaged element holder
- Install a new element holder
- Install the new element
Removing the Old Element
When I ordered my new element from L&L, it came with a very helpful instruction manual, detailing the steps involved in removing and installing new elements and element holders. So, I just followed the instructions!
New kiln elements (standard small) straight from L&L. I ordered a few extra, just in case.
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It is suggested that all elements be replaced at the same time. If element failure is due to age, this makes sense since if one element dies, the others will most likely follow close behind. However, this is quite an expense. My kiln elements run about $40 each, for a total of $240 if I want to replace all the elements at once. Since the element failure was due to contamination, I decided to risk just replacing one element this time – we’ll see how that goes.
Tip: If you are ordering new elements for the first time, consult with your kiln manufacturer or supplier to verify the exact kiln element you require. Once you receive the new element, it is also a good it idea to inspect it to make sure it is the same width with the same number of coils per inch as your old elements. It can’t hurt to check the resistance of the new element as well, since all elements in the kiln should have the same resistance when new.
Step 1: Remove the Element Boxes
♦ In order to gain access to the element terminal bolts, use a nut driver or screw driver to remove the screws attaching the element box to the kiln body.
The element boxes on my kiln are attached to the kiln body by hex-headed screws. Since the screws on my kiln were a bit rusty, I used both a 11/16” nut driver and a flat head screw driver to remove the screws. At some point in the near future, I will replace the old screws with nice new shiny screws that will be easier to remove (I probably should have thought of that before beginning this project!)
The element boxes on my kiln are attached to the kiln body by hex-headed screws. Since the screws on my kiln were a bit rusty, I used both a 11/16” nut driver and a flat head screw driver to remove the screws. At some point in the near future, I will replace the old screws with nice new shiny screws that will be easier to remove (I probably should have thought of that before beginning this project!)
Step 2: Take a Picture of the Element Terminal
♦ Photograph or sketch the element terminal, noting the order of attachments.
The elements are attached to the terminals in a specific order, sandwiched between nuts, washers, wires and other elements. Taking a picture of the assembled set up will guarantee the order can be replicated correctly when reassembling. I actually took a few pictures from different angles, just to make sure I could see all the connections.
The elements are attached to the terminals in a specific order, sandwiched between nuts, washers, wires and other elements. Taking a picture of the assembled set up will guarantee the order can be replicated correctly when reassembling. I actually took a few pictures from different angles, just to make sure I could see all the connections.
Pictures of the element terminal from different angles. From these pictures, I am able to see the order of all the connections so that I can replace the components properly after the new element is installed.
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If you don’t have a camera handy, carefully sketch out a detailed diagram of the order of the components. It also helps to label everything as you remove the pieces from the element terminal bolt.
At this point, also familiarize yourself with how your kiln is wired. My kiln is wired in series, with two elements per level (there are three levels in my kiln for a total of 6 elements). Each level has one terminal with three terminal bolts: top left, bottom left and right. The top element of the level connects to the top left terminal bolt and the right terminal bolt. The bottom element of the level connects to the right terminal bolt and the bottom left terminal bolt.
At this point, also familiarize yourself with how your kiln is wired. My kiln is wired in series, with two elements per level (there are three levels in my kiln for a total of 6 elements). Each level has one terminal with three terminal bolts: top left, bottom left and right. The top element of the level connects to the top left terminal bolt and the right terminal bolt. The bottom element of the level connects to the right terminal bolt and the bottom left terminal bolt.
Step 3: Disconnect the Element from the Terminal Bolts
♦ Using a 3/8” combination wrench or nut driver, remove the nuts, washers, wires and element ends from the terminal bolts.
I began with the left element terminal bolt by unscrewing and removing the nut, washer, wire, second nut and second washer. Next, using a pair of needle nose pliers, I unwrapped the element end from the terminal bolt and straightened it out as much as possible
I began with the left element terminal bolt by unscrewing and removing the nut, washer, wire, second nut and second washer. Next, using a pair of needle nose pliers, I unwrapped the element end from the terminal bolt and straightened it out as much as possible
Top left terminal bolt with the nut, washer, wire, second nut and second washer removed. The left element end is still wrapped around the bolt.
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Left element end unwrapped from the top left terminal bolt. The tail needs to be straightened out before it can be pulled through the element hole.
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Removing the element from the right terminal bolt was a bit different. Since my kiln is wired in series, the second element is also attached to this terminal bolt and is closest to the end of the bolt. I wanted to remove the first element end from the terminal bolt without removing the second (since I am only replacing the top most element), therefore, I could not loosen the nuts and washers very much and had a hard time removing the first element end using just a pliers. Using a wire cutters, I cut the first element end before it met the terminal bolt (between the kiln and the bolt), and was then able to unwrap it from the bolt with the pliers without removing the second element.
Left and right element ends removed from the top left and right terminal bolts. The element ends have been cut and straightened to allow them to pass easily through the element holes in the kiln body.
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Top left and right terminal bolts with the old element ends removed. The second element ends remain on the right and bottom left terminal bolts.
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Step 4: Remove the Element from the Kiln
♦ Pull the element ends into the kiln, and remove the old element from the holder.
Making sure that the two ends of the element are as straight as possible will allow the ends of the element to be pulled smoothly into the kiln with minimal damage to the kiln brick. The element can then be removed from the element holders quite easily.
Making sure that the two ends of the element are as straight as possible will allow the ends of the element to be pulled smoothly into the kiln with minimal damage to the kiln brick. The element can then be removed from the element holders quite easily.
Beginning to pull the right element end through the element hole and into the body of the kiln.
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Right element end pulled through the hole in the kiln wall and into the kiln body. The element is beginning to come out of the holder.
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The L&L instruction manual suggested using a flat head screw driver to remove the element if there was any difficulty popping the element from the holder. There was only one especially sticky spot where I had to resort to this method - the element came out with little trouble everywhere else.
Pulling the old element out from the element holder. For the most part, it was easy enough to remove with just my fingers.
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There was only one spot where the element proved difficult to remove. A screw driver was able to provide the necessary force to pry out the element.
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Removing the Damaged Element Holder
Once I had removed the old element, I inspected the element holder where the failure had occurred. There was an obvious charred and discolored area with a mound of what I guessed to be melted element and possibly other contamination fused onto the element holder. The discoloration is not necessarily a problem, but it is possible for the material left over from the element failure to cause failure in the new element if it is not removed.
Using some metal carving tools and a screw driver, I attempted to scrape the melted metal from the element holder, with little success. I soon decided it would be best to just replace the holder itself. This decision made me a bit nervous, because it required either 1) disassembling the top ring of my kiln and replacing the whole affected kiln brick, or 2) chiseling out the old element holder. Both options sounded like they have the potential to cause a lot of damage to my kiln, but eventually I opted to method #2, as hopefully easier.
Melted gunk in the element holder where the element failed. This has go to go!
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Measuring the old element holder, I determined I needed a 3-inch replacement, and ordered it from my kiln manufacturer’s website.
On a side note, not all kilns have element holders to keep the elements in place. Many kilns, like my larger Blue Diamond kiln, just have channels carved directly in the kiln brick into which the elements fit. Personally, I really like the element holders. Since they are made of ceramic, I have found they are much sturdier than the alternative. The element channels in my Blue Diamond kiln (which has been fired probably less than 20 times its entire life) are already crumbling, and the elements falling out.
On a side note, not all kilns have element holders to keep the elements in place. Many kilns, like my larger Blue Diamond kiln, just have channels carved directly in the kiln brick into which the elements fit. Personally, I really like the element holders. Since they are made of ceramic, I have found they are much sturdier than the alternative. The element channels in my Blue Diamond kiln (which has been fired probably less than 20 times its entire life) are already crumbling, and the elements falling out.
Tip: Wear safety glasses when removing the old element holder to protect your eyes from flying debris.
Step 1: Chisel out the Old Element Holder
♦ Using the flat head screw driver (or chisel) and hammer, break the element holder into small removable pieces.
Chiseling out the old element holder with a flat head screw driver and a hammer.
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Partially removed element holder.
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Worried about accidentally damaging the soft kiln brick behind the holder, I began the process with gentle taps, but soon got a feel for the amount of force I needed to break the holder. It was actually a lot easier than I had suspected, and in a few minutes, I had removed the element holder with only the smallest amount of damage to the kiln brick.
The element holder has been removed. A few nicks to the kiln brick behind, but nothing too bad.
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Shards of the old element holder - look at that scorched section! The molten metal melted a nice hole in the holder, right down to the kiln brick!
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Step 2: Prep the New Element Holder
♦ Use a pair of pliers to remove an extra flange from the new element holder.
The new 3-inch element holder I ordered from L&L comes standard for both new kilns and repair parts. The holder has two flanges on bottom and two on the top that secure the element holder within the element holder channel. However, with all four flanges intact, it is impossible to slide the holder back into the kiln brick channel for a repair. Therefore, the L&L manual suggests using a pair of pliers to remove the back bottom flange from the holder.
New L&L 3-inch element holder. Note the 4 flanges (2 on the top and 2 on the bottom).
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As with chiseling out the older holder, I was a bit nervous snapping off the flange, and began hesitantly (the manual says complete this step carefully, after all). Again, though, the job was simpler than expected. The flange was easily removed with a few “bites” from the pliers.
Nipping off the bottom back flange of the new element holder with a flat nose pliers.
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The flange has been trimmed from new element holder, and it is ready to be installed!
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Step 3: Fit the Prepped Holder into the Holder Chanel
♦ Test the holder for fit in the element channel, and make adjustments as needed.
After breaking off the flange from the holder, I tested the holder in the element channel and realized that the flange was still protruding a bit too much in places for it to fit easily back into the kiln. Therefore, I grabbed my pliers again, snipped off a few burrs along the flange line and retried the holder in the kiln. A perfect fit! Even though the new holder is missing a flange, it will remain securely in its channel, and the L&L manual says that there is no need for cement.
After breaking off the flange from the holder, I tested the holder in the element channel and realized that the flange was still protruding a bit too much in places for it to fit easily back into the kiln. Therefore, I grabbed my pliers again, snipped off a few burrs along the flange line and retried the holder in the kiln. A perfect fit! Even though the new holder is missing a flange, it will remain securely in its channel, and the L&L manual says that there is no need for cement.
The new element holder installed! Not a perfect match to the original element holders, but if it holds the element, I'm happy!
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Installing the New Element
Moving right along! After removing the old element holder and installing the new one, I was feeling very pleased with my handy work and ready to install the new element.
Step 1: Stretch the New Element
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♦ Use a bench vise to secure one end of the element, and gently stretch the element to the correct size.
Some elements come pre-stretched, however, it’s always a good idea to measure your element to make sure it is the correct size before attempting to install it. L&L states that their replacement elements are shipped slightly understretched and must be adjusted for the final fit. The kiln manufacturer should provide the exact length for the element – 55.5 inches for my kiln (measuring the coiled section of the element only and not the straight tails). My element turned out to be about 4 inches too short. Using a bench vice, I clamped one end of the new element securely to my work table, and marked off 55.5 inches from the vice where the element coils begin. I then used my hands to slowly and gently stretch the element as evenly as possible, working from one end to another and stretching the element in small increments. Stretching the element unevenly may create uneven firing. And be careful not to overstretch the element. Overstretching can cause the element to bunch in the holder, decreasing the life of the element. Don’t worry if you don’t have a bench vice to secure the end of the element. Just grab a friend and have them stand firmly on the element tail instead. |
With one end of the new element gripped firmly in a bench vise, carefully stretch the element to the correct length.
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Tip: Be sure to wear safety glasses when stretching the element. If the element comes loose while stretching, it can cause injuries.
Step 2: Install the New Element
♦ Working from the inside of the kiln, insert the two straight ends of the element through the element holes.
Pull the element tails from the outside of the kiln so that the coils are pressed against the inside kiln wall. The rest of the element will hang down in a loop.
Pull the element tails from the outside of the kiln so that the coils are pressed against the inside kiln wall. The rest of the element will hang down in a loop.
The long ends of the new element have been pulled through the element holes from the inside of the kiln.
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The new kiln element before installation into the element holder, hanging down in a loop.
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♦ Insert the element into the element holder.
Working around the kiln, I used my hands to press the element into the holders. The element was a bit springy with a tendency to pop out of the holder, so the process required a firm touch to lock the element in place. The L&L manual suggests that a flat head screwdriver may be useful for this task, though I found I did not need one.
Working around the kiln, I used my hands to press the element into the holders. The element was a bit springy with a tendency to pop out of the holder, so the process required a firm touch to lock the element in place. The L&L manual suggests that a flat head screwdriver may be useful for this task, though I found I did not need one.
Working around the kiln pressing the new element into the element holders.
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Newly installed element.
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Step 3: Reconnect the Element Ends to the Terminal Bolts
Here’s where I looked back to all those handy pictures I took at the beginning of the process. They detailed exactly the order in which the elements, washers, nuts and wires should be reconnected – a life-saver, let me tell you!
♦ Attach the left element tail to the top left element terminal bolt, and replace the washers and nut.
As with disconnecting the elements, I began with the left most element since it was the easiest. Using a needle nose pliers, I wrapped the left element end around the top left terminal bolt one time in a clockwise direction. I made sure that the element end was wrapped tightly around the terminal bolt, and pressed firmly against the terminal nut. I then replaced the washer and second nut and snipped off the excess length of element end with a wire cutter. I left the wire and final washer and nut off for the time being since the wire would be in the way when I replaced the right element end.
As with disconnecting the elements, I began with the left most element since it was the easiest. Using a needle nose pliers, I wrapped the left element end around the top left terminal bolt one time in a clockwise direction. I made sure that the element end was wrapped tightly around the terminal bolt, and pressed firmly against the terminal nut. I then replaced the washer and second nut and snipped off the excess length of element end with a wire cutter. I left the wire and final washer and nut off for the time being since the wire would be in the way when I replaced the right element end.
Wrapping the left tail of the new element around the top left terminal bolt with a needle nose pliers.
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♦ Wrap the right element end around the right terminal bolt one time in a clockwise direction.
Since I left the second element of the level attached to the terminal when I removed the first element, I replaced the right end of the new element in the original position behind the second element end (closest to the terminal board). The washer and second nut were already in place, so I merely tightened them with a combination wrench. I snipped off the excess element wire with a wire cutter, and then tightened the second element end, second washer and third nut.
Since I left the second element of the level attached to the terminal when I removed the first element, I replaced the right end of the new element in the original position behind the second element end (closest to the terminal board). The washer and second nut were already in place, so I merely tightened them with a combination wrench. I snipped off the excess element wire with a wire cutter, and then tightened the second element end, second washer and third nut.
The right end of the new element has been wrapped around the right terminal bolt in back of the second element end. The long tail of the element has not yet been cut.
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Tightening the nut in front of the right end of the new element on the right terminal bolt with a combination wrench.
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♦ Replace the wire on the top left terminal bolt.
Don’t forget that left wire! I slid the wire onto the left terminal bolt, followed by another washer and nut. Tighten, and done!
Don’t forget that left wire! I slid the wire onto the left terminal bolt, followed by another washer and nut. Tighten, and done!
Reattaching the wire, washer and nut to the top left terminal bolt.
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Reassembled terminal bolts with the new element connected.
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Step 4: Replace the Cover Boxes
♦ Using a nut driver or screw driver, reattach the element boxes to the kiln body.
Just to make sure I reattached everything to the terminal bolts correctly, I once again consulted my photos before replacing the element box covers. When I was satisfied, I screwed the covers back in place.
Just to make sure I reattached everything to the terminal bolts correctly, I once again consulted my photos before replacing the element box covers. When I was satisfied, I screwed the covers back in place.
Reattaching the element cover box back onto the kiln body using a nut driver.
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We’re almost done, I promise! Just a few extras to finish up on the right note.
♦ Vacuum out the kiln.
Chances are that while you replaced the element, some errant brick dust has collected in the element holder and kiln floor. After all, kiln brick is quite soft, and easily flakes with the slightest abrasion. Since the brick dust can harm the elements, as well as ceramic pieces while they are firing, I like to vacuum out the element holders and the kiln in general after I work on it (and actually before all firings, just to be on the safe side).
♦ “Season” the new element.
A new element can sport some residual machine oil and such from manufacturing. It’s a good idea to run the kiln empty once after kiln elements are replaced in order to oxidize the new element. The L&L manual suggests a firing to cone 5. I just put the kiln on high for an hour, and that seemed to suffice. I could smell residual fumes for the first few minutes, but after than, it was clear sailing.
♦ Vacuum out the kiln.
Chances are that while you replaced the element, some errant brick dust has collected in the element holder and kiln floor. After all, kiln brick is quite soft, and easily flakes with the slightest abrasion. Since the brick dust can harm the elements, as well as ceramic pieces while they are firing, I like to vacuum out the element holders and the kiln in general after I work on it (and actually before all firings, just to be on the safe side).
♦ “Season” the new element.
A new element can sport some residual machine oil and such from manufacturing. It’s a good idea to run the kiln empty once after kiln elements are replaced in order to oxidize the new element. The L&L manual suggests a firing to cone 5. I just put the kiln on high for an hour, and that seemed to suffice. I could smell residual fumes for the first few minutes, but after than, it was clear sailing.
And that’s it, folks!
I must say that I was quite proud of myself for replacing a kiln element and element holder without outside assistance. And I was especially excited when my first firing with the new element did not explode my kiln due to an electrical malfunction. Wahoo to another successful firing without burning down the studio!
I must say that I was quite proud of myself for replacing a kiln element and element holder without outside assistance. And I was especially excited when my first firing with the new element did not explode my kiln due to an electrical malfunction. Wahoo to another successful firing without burning down the studio!
