New Elements Are In

[Bill T.]

After hundreds of bisque and Cone 6 firings  my Skutt 1027 was beginning to lag down.  Time for new elements.  Having never done this before I was a bit concerned not with the actual process of replacement and rewiring, but with getting the old elements out without tearing up the element channels.  Thank goodness the 1027 is sectional, and I could put each section on the bench and work with good view and not with my bu...up in the air while bending down in a hole.  I learned the trick to getting the elements out without damage on the first one.  Don't just pull...carefully twist the element out of its channel.  Little back and forth twisting motions.  Did not damage a single channel.  Probably over zealous in the use of the element pins, but Skutt sent a whole lot with each element so I used more than what was first in it.  New thermocoupler, cleaned the outside case, painted the stand, cleaned and oiled the exhaust vent, it almost looks like a new kiln again.  So tomorrow a breakin firing with cone packs to check everything out.   

[neilestrick]

Congrats! Next time it'll be even easier. There's nothing all that difficult about changing elements, but familiarity with the process makes it a lot faster.

[Karen B]

Very timely post for me, Bill.

 

I am thinking that I have to replace my elements (same kiln as you).

Before I replaced the thermocouple the cone 6 firings took 2 hours longer to fire than normal.

Cone on the bottom shelf was bent to 5:00 the middle shelf was 3:00 and the top was 2:00.

 

After I replaced the thermocouple, the kiln still had a very hard time reaching cone 6. It stuck at 2130 like 45 mins, I was afraid it would turn off after awhile at that temp, so I hit "stop" and put in a direction to go directly to 2245 (which is the normal cone 6 temp for this kiln). The cones were completely bent and tips melted.  I had replaced the thermocouple before this firing.

 

My glazes looked like crap, as they have for the last few firings. So, do you or Neil think that I need to replace the elements?

I've had the kiln for 10 yrs, but only fire a max of 10x a year, (including bisque) usually less.

 

And to Bill, did you have to use a tool to bend the elements? Although I am pretty handy with electrical work, this makes intimidates me for some reason.

  I am thinking I should hire someone to do this.  

 

Thanks for any help. I'm sorry if I am usurping your post Bill.

Karen

[Bill T.]

Can't be much help with the first questions, only that my firings had increased in time about an hour and hard to reach 2180 cone 6 for me.  I fire 150 degrees per hour for the last 200 degrees, and this is where it seemed to take too long. 

 

You do not have to bend the Skutt elements.  They are pre-bent for each angle.  You do have to hold them up in a straight line so they can settle to the correct curvature.  Then keeping all in line  just work your way around the element holders.  Skutt includes pretty good directions, 2 ceramic spacers, 2 new connectors and lots of pins.  There is also a video on You Tube made by Skutt.  It really is as easy as the lady makes it look.  Check it out.

[Karen B]

Thanks Bill!

[clay lover]

I just did the same kiln for the first time.  It took us a long time but we stopped and started a lot.  It is not technically difficult, just a bit tedious.  We marked the box and what wires went where before cutting the box off, that was VERY comforting and made putting back together much quicker and less stressful.

  Don't be afraid and you don't need to hire it done, just go as slow as you need to,  to check things as you go along.  Probably good to only open the element that you are ready to install, so that you can't mix up the middle with the 2 hotter ones.  My former teacher said run it 1 ramp to 1,000 * to burn off coatings and then you ARE GOOD TO GO.  I DID HAVE A PLACE OR 2 THAT I ADDED PINS AFTER THE TEST RUN, AND THERE WAS SOME ODER THE SECOND FIRING, BUT NOT FOR LONG..

 

sORRY, CAPPS KEY IS SNEAKY.

 

Bill, that is the temp I put in for ^6, do you soak aT THAT TEMP TO GET CONES DOWN?  I GO A BIT SLOWER TO PEAK TEMP, 115* / HOUR.

[Pres]

Changing elements the first time is always tricky. The first kiln I changed was an square top loading Amaco. OHhhhh what a job. I ended up un-assembling the whole thing and then putting the elements in as I put in the rows of bricks. Some of the bricks had glaze damage from the previous user so bricks had to be replace to do the job decently. Naturally these bricks were in the bottom sides of the kiln.

 

The next kiln I replaced elements in was an L&L that we had purchased new. Sectional, element holders, the job was a dream. The only iffy was having to stretch the elements to the correct length. All else was easy. The more experience you get at it, the easier things go, and the more difficult tasks like replacing switches and wiring becomes everyday.

[neilestrick]

If your firings are taking a lot longer, and everything else is functioning as it should (thermocouple, relays, etc), then you probably need to replace the elements. for the first firing with a new set of elements,  you should do an empty firing to cone 08. You're not just trying to burn the oil off the element wire, but rather this builds a layer of oxidation on the surface of the elements that helps protect them from all the stuff that burns out of your clay and glazes during a firing. Ramping to 1000F degrees is not sufficient.

 

Skutt elements are usually dead on as far as length and corner bends are concerned, and their pins are perfectly straight. Pinning the elements at each corner is the most time consuming part of the process. I recommend just doing one ring of of the kiln at a time, so you have the other ring(s) as a reference if needed when wiring it back up.

 

L&L elements are usually slightly short, but that's because at the factory they prefer to stretch them into the corners. Personally, I have problems with them popping out when there's tension in them like that. So I prefer to have them just lay into the holders with little to no tension, which means I have to stretch them out a bit. Even with doing that it's way faster than putting in pins.

 

Element coils can expand in diameter as they age, so with elements that sit into brick grooves you can get some chipping of the grooves when you take them out. Just go slow and twist them. With the L&L holders that's not an issue, however if you fire your elements to death, it's possible for them to stick in the hard holders, which means digging them out in little chunks. I've only seen that happen once, though, and those elements were beyond toasted.

[Bill T.]

Clay lover:   Sorry can't figure out the quote function.  I hold 10 minutes at 2180 just to settle everything down.  No scientific reason except it seems to work with the glazes I use. 

 

I'm glad this topic has generated some interest and a lot of good suggestions from the folks that have done it a lot.  Maybe you will feel more comfortable tackling the job by oneself.  . 

[Karen B]

Thanks for the help! The personal experiences are great. I will gather my nerves and do it myself. 

[clay lover]

Bill T, thanks.  When you say you get  a ^6, do you use self supporting cones and do you call tip touching the shelf as the true cone?  Curious, since I seem to need to fire a good bit longer to get that.  I hold at 2180 for 25 min.

[CarlCravens]

I was reading Orton's "Cones and Firing" pamphlet last night, and they consider the cone to be fully bent when the the tip is even with the top of the cone plaque or pat.  The cone is supposed to stick 1-3/4 to 2" out of the top of the pack.  If it's a free-standing cone, bending to even with the top of the base section is the same (the free-standing cone has 1-3/4" of cone above the base).

 

http://www.ortonceramic.com/wp/wp-content/uploads/cones-and-firing-booklet.pdf

 

It was an interesting read.

[clay lover]

Thanks, Carl, that was an informative read, and helped me answer several q' s.