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.
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!
- Remove the old element
- Remove the damaged element holder
- Install a new element holder
- Install the new element
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 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.
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.
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
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.
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.
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.
♦ 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.
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.
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.
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.
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.
Don’t forget that left wire! I slid the wire onto the left terminal bolt, followed by another washer and nut. Tighten, and done!
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.
♦ 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.
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!