Paragon E10: multipurpose?

Moira HFG · May 07, 2014, 02:28:07 PM

Oh dear.

I set the kiln to Seg 1: 180ºC/h to 600ºC
Seg 2: 999ºC/h to 1210ºC
Seg 3: 270ºC/h to 600ºC

The clay I was using was supposed to fire at 1200 to 1230ºC, to give an interesting stone-like black finish.

All was fine up to around 900º, but after that the rate of temperature rise got progressively slower. By 1000º it seemed to be really struggling, and at 1030º I noticed the paint around the bead door starting to discolour. I lost my nerve at this point and skipped to the next segment.

According to the uk Paragon dealer website, this kiln even with bead door and window, should deliver up to 1230ºC. It says specifically it is a multipurpose kiln, suitable for glass or clay. I got mine second-hand, but it wasn't old or heavily used.

So: either the temperature isn't reading correctly; or there's some fault preventing it from reaching full temp; or I chickened out too soon; or the information on the website is wrong. I'll ring them tomorrow to see what they say.

I notice that the US sellers quote the maximum temp for this model as 2000ºF - which is 1093ºC.

I hope it is some sort of fault, I'll be very disappointed if this kiln can't fire clay after all.

(If not, I've got an SC3 with a bigger price tag!)

Moira

Lee - Kilncare · May 07, 2014, 03:12:53 PM

Hi bud, the bead door is the problem. That kiln is indeed a multi function type kiln but, I sure it even says on Paragons site somewhere, the bead door can severely slow the kiln down and even may reduce the maximum temperature of the kiln.
It looses that much heat through the bead door, it was even removing your paint, so pretty hot.

Have you got some ceramic fibre at hand that you can block the hole on the inside of the bead door with?

Zeldazog · May 07, 2014, 03:30:01 PM

Quote from: Moira HFG on May 07, 2014, 02:28:07 PM

According to the uk Paragon dealer website, this kiln even with bead door and window, should deliver up to 1230ºC. It says specifically it is a multipurpose kiln, suitable for glass or clay. I got mine second-hand, but it wasn't old or heavily used.
....

I notice that the US sellers quote the maximum temp for this model as 2000ºF - which is 1093ºC.

If you mean the UK Paragon site that I think you mean, their website is littered with information errors. For example, take a look at the E12 - the power rating stated on the UK site is different to that on the Paragon Web US site - and I am pretty sure that the manufacturers have got the power rating and maximum temperature right and that UK site may have made some errors. In this link, http://www.paragonweb.com/E10.cfm Paragon even say Low Fire ceramics.

Lee - Kilncare · May 07, 2014, 03:47:03 PM

Thats is indeed correct Zelda

)

ajda · May 07, 2014, 03:59:15 PM

I have a Paragon Caldera with removable bead-door section (fits between base and main body) and a glass viewing window in the lid. Without the bead door section and with the window plugged with ceramic fibre it'll reach its maximum, something over 1250C. With the window unplugged it'll only get to about 1150C. And with the bead-door section installed it'll only get to about 1050C.

Zeldazog · May 07, 2014, 03:59:40 PM

Quote from: Lee - Kilncare on May 07, 2014, 03:47:03 PM
Thats is indeed correct Zelda )

'course it is Lee, you know me

Moira HFG · May 08, 2014, 10:48:01 PM

Thanks for that, everyone.
What you say makes sense, and I'll get some ceramic fibre sheet or block, fill in the gaps and try again.

Interestingly when I rang Cherry Heaven today, the man said these kilns are only designed to heat to 1095ºC, unless you request them to be upgraded to 1230, 1260 or 1290. He suggested I email Paragon in the US with the serial number, to see what temperature this particular kiln was built to go to. Wha??? This conflicts with what his website says by a mile.

Well, I've emailed them; but it sounds odd to me. Why build a firebrick kiln and advertise it as a 'multipurpose kiln' then limit the temp? I see that making holes in the door presents a challenge to it, but hopefully with the gaps plugged I'll have better luck.

Zeldazog · May 08, 2014, 11:16:14 PM

Well, it *is* a multipurpose kiln to be fair - by going up to over 1000C, that covers earthenware of other specially developed low firing clays. Still will do glass, enameling, suitable as a bead kiln with the door option, it'll do metal clay.... just not suitable for most stoneware or porcelain (except to bisque fire)

Check out Valentines Clays - there are other suppliers, Valentines is the only one I've bought directly off - they do great range of different clays and you can filter the lower firing ones:

http://www.valentineclays.co.uk/catalog/product

Unfortunately the gorgeous black clays are all high firing, I think all the black clay bodies I've come across were high firing

You must be so disappointed Moira, it's awful when you buy something (especially of considerable expense) and it doesn't do what you thought it would be able to.

Moira HFG · May 08, 2014, 11:50:46 PM

Thanks, Zeldazog, I hadn't come across Valentines. It does help having them listed by firing temp - I got my clay from Bath Potters and had to check out each one

. The other stuff I got from them is plain buff which fires at 1100, so I hope I will be able to cook that high enough for slumping moulds, when I block the door gaps.

Yes, I was disappointed. Oh well, I didn't pay full price, and it does everything else very nicely.

Shame about the black clay, I had some lovely ideas....

Zeldazog · May 09, 2014, 12:33:38 AM

Quote from: Moira HFG on May 08, 2014, 11:50:46 PM
Thanks, Zeldazog, I hadn't come across Valentines. It does help having them listed by firing temp - I got my clay from Bath Potters and had to check out each one . The other stuff I got from them is plain buff which fires at 1100, so I hope I will be able to cook that high enough for slumping moulds, when I block the door gaps.

I am pretty sure slumping moulds (well the ones I have) are only fired to bisque - I am not sure if they're made of buff stoneware or porcelain, but they're defnitely not fully fired as they haven't vitrified, so they cannot have matured fully. When you brush on the kiln wash, it absorbs the moisture like a sponge.

From memory, I think we did bisque firings to the 900-950 range so you should be able to make moulds from your buff.

Now I was told that clay is as much about heat-work as it is about top temperature, so it may be worth an experiment, if you're brave enough, with the black clay and a VERY long soak at the top temperature but I honestly don't know if any soak would be long enough for it to absorb enough heat over time to make up for the short fall in temperature. I did some ceramics at uni, but not enough to get that technical!

Moira HFG · May 19, 2014, 08:53:02 PM

I finally had a reply from Paragon HQ. They said this kiln will only go up to 1093ºC.

It's a bit annoying. Even the metal plaque on the side with the model and serial number says 'maximum temp 1230ºC' !!
The tone of the email wasn't very friendly, so I didn't feel like asking the 'what if I pack the gaps with ceramic fibre' question.

Well, blast it, I'll stick to glass making for now. The clay will be useful for making plaster casts, which I know will fire with no problems.

Perhaps I'll have a go at bisque firing when the temp outdoors drops a bit!
The box of goodies that the kiln's previous owner gave me has something in it that looks like ceramic fibre block. (How will I tell? Stick a piece in the kiln and see if it survives firing, I suppose?)

Many thanks to you all for your advice.