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jools02
21-10-2009, 07:31 AM
Hi all, I'm very new to jewellery making but have done a course for PMC+ fingerprint jewellery recently. I've just got my first kiln, an EFCO 135 with a Uhlig controller and a ceramic plate to protect the bottom.

However I'm not sure how to use it! It doesn't come with instructions. I asked the seller but she never used it for PMC before. She says she used to use it on setting 8 which was about 950c so I'm guessing its prob about setting 7 for the 850c required for the PMC+?

If anyone else has one of these I'd be grateful for help with the following:
How do I get it to 850c for firing PMC+ and how long do I need to fire it for?
Do I put the clay straight onto the ceramic plate?
How many pieces can I fire at once?

Thanks all!

bustagasket
21-10-2009, 07:38 AM
Welcome to the forum Jools, i am sure someone will soon be able to help you as there are a lot of kiln owners on here, and if they dont own your particular kiln i would be very surprised if they werent able to point you in the right direction. You have come to the right place for help :D:~:

MuranoSilver
21-10-2009, 08:09 AM
Sorry the controller on my kiln is a SentryExpress 3
I noticed Cherry Haven sells your model though so maybe they might be able to sell you some intructions :)
nicola x

Solunar Silver Studio
21-10-2009, 08:36 AM
Hi Jools and welcome to the forum. I am still very much a beginner and I have a kiln what has a programmer which I use for pmc and an Uhlig that doesn't which I use for 'mucky' stuff!! I also am a firm believer in experimentation!! If I was in your position I would sacrifice a piece of pmc in the way that is described here

PMC GUILD - Getting Started in Precious Metal Clay - FAQ: Firing PMC (http://www.pmcguild.com/gettingstarted/faq_firing.html)

I think it is very useful to know exactly what to look for as the warning signs that everything is about to melt into a blob!! Then you can set your controller a notch below danger point. As pmc3 can be fired at such a range of temperatures I would be inclined to stick with this until you can afford a higher spec kiln!!

I have found this chart with the range of temperatures which I think is very useful. I used to fire at 750 for half an hour but then Nic (Murano) said she fires at 820 (I think!!) so I now do it around there too....Nic knows lots!!!:Y:

http://www.pmcguild.com/download/Tech_Data/PMC_Relative_Strength.pdf

I put my pieces onto a removable ceramic shelf and so long as they don't touch each other (or else they will fuse together) you can fire a sheetfull. You may find that you have cool spots and hot spots in your kiln - but you will learn that the more you do!!

I don't think it makes much difference whether you put them into a cold kiln or a hot one...although there is probably more chance of damage from thermal shock if you put it in a hot one. The binder will burn off at quite a low temperature and it looks like the kiln has caught fire if you have a lot of bits in there - but it only lasts a couple of seconds!!

I think when you first start you have to accept that some things won't work...and don't put anything precious in (like commission work!) until you are sure of your temps!!

Hope some of this helps!!:)

jools02
21-10-2009, 09:01 AM
Great thanks everyone! Solunar, I've made a couple of PMC matchsticks to test it with. I think I'll try 20 mins on setting 7 first. The kiln came with a ceramic plate and a couple of funny metal things - I think these are stilts. Do I just put the plate onto a stilt? Sorry if these questions sound stupid but I've never used a kiln in my life.

So, should I just stick the kiln on at setting 7, wait until the inside goes red and stick my matchstick in?

jools02
21-10-2009, 10:08 AM
Just to update you all, I just fired a test piece (matchstick) on setting 7 for exactly 20 mins and it bent. Its perfect! I'm so excited!!

Solunar Silver Studio
21-10-2009, 10:28 AM
Huh!! It took me so long to write this that you've done it all already!! Well Done!! Onward and upward!!!

Hi Jools. The metal stilts are supplied with these kilns because a lot of people use them for enamelling. If you make an item that has enamel on both sides (counter enamel on the back and the decorative stuff on the front) you have to prop it up on one of these stilts to stop it sticking to the shelf...you just get 3 tiny points of contact with the metal stilt then.

You could try a balancing act if it would entertain you...but on health and safety grounds I wouldn't try it!![-X

I support my ceramic sheet/shelf whatever you call it on a mesh trivet type of thing like this...

http://www.homecrafts.co.uk/prodimg/E061_1_Zoom.jpg

This allows you to insert a kiln 'fork' underneath the whole thing to take it out safely. Mine was supplied with all the other kiln tools and 'furniture' that I got with my Uhlig kiln...specifically for enamelling many, many moons ago!! (In fact...I have just found the exact kit that I bought still exactly the same....except the price which was £99.95 back in 1994!!!)

http://www.corbykilns.co.uk/images/large/enamelling/enamelKit_LRG.jpg

If you have nothing stable to support your shelf on then it will have to sit on the bottom of the kiln and you will need to let the kiln cool down sufficiently after firing to allow you to remove it safely with whatever tools you have.

And yes...I would heat up your kiln...carefully put in your shelf and 'matchstick' then shut it up again. My kiln takes about 1 minute to regain the heat it has lost in opening the door so wait a minute or so before assuming it is at full temperature and doing any timings... Then if it shows no sign of melting after your timed period but it appears to have sintered properly and is good and strong you know you have a reasonabe temperature for firing. Then I would put it back in and I would crank it up to the next setting and see if it melts then...and then keep going until you see that shimmering and it starts melting. Then you know what setting is too high for pmc. You will then have an idea of the range that you can work in...

Just for heaven's sake take care if you don't have the proper tools for using a kiln...and wear gloves...even if you only have the sort of canvas gardening gloves...it will help to protect your hands from the heat...or you will feel like your nails are melting!!! (I would advise removing nail varnish too if you don't wear gloves!!) And if you take a 'hot' shelf out of the kiln put it onto a soldering block/piece of slate/terracotta tile or other flameproof surface or you will end up burning things!!

jools02
21-10-2009, 10:45 AM
Oh sorry Barbara, I was just itching and the kiln was calling out to me! But still you've given me a lot of helpful advice there. Thank you!!
Julie