Can you identify this Kiln?

Started by Beansprout, January 03, 2013, 06:02:55 PM

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Beansprout

I have just been loaned this small enamelling kiln from a family Friend. The only writing on it is "horst uhlig"... Pics below!

I'd like to see if I could use it for bead annealing, but there are no instructions, no obvious temp control system, so it may be a little difficult to regulate the annealing cycle... But I'd like to give it a try!

Could anyone identify it? Maybe with a handy set of instructions as well!! I'll have a few searches on google myself but I am not very familiar with kilns as some of you others may be :D

It came with a white dial box, it moves OK from 12 to 3 or 4 o'clock, but is stiff between 3 and 12. It clicks at 12 and 4











Plug to show scale of interior





helbels

#1
1) It looks like an older model of this one: http://theenamelshop.com/enamelling_kilns.html  Not sure if the controller is still the same, but it might be worth emailing them to ask?

2) This guide also refers to the kiln and implies that it doesn't have a temperature controller as such - you kind of do it by eye:  http://teachersunderground.co.uk/Metal/enamelling.pdf

3) Oh, and here is the manufacturer's website in Germany: http://laborofen.com/de/  I would try emailing them your pictures and see if they can help - don't worry about the language barrier as most Germans speak English better than we do.

It looks like it's possible to buy a better controller to suit the kiln than the old one currently fitted.

Beansprout

Helbels, thank you! I also fell across theenamelshop link as well. The PDF you linked to was quite helpful!

I've sent an email to Laborofen peoples asking a whole load of questions, including if they could recommend a thermocouple or a way to read the temp using the colours in the window!

The PDF says you have to leave the door open to release the heat if you're using it for long periods of time... But if I'm going to be using it for anealing beads (if it's at all possible), the mandrels sticking out the bottom should be sufficient?

I've found the regulator one of the sites recommended: U0001 --- Would they roughly indicate the temp? One's got a light and a temp controller... Guessing it works like an oven, when temp is reached light goes off?
http://www.hindleys.com/catalog/product_info.php?products_id=2561
(top left) http://theenamelshop.com/regulators_pyrometer.html

I'll try out the white controller and the kiln tomorrow!

helbels

You're now asking questions that are way beyond my levels of kiln expertise  ;D  But I'm sure someone more knowledgeable will be along shortly!

oliver90owner

#4
Guessing it works like an oven, when temp is reached light goes off?

Not quite.  Without a temperature sensor, there can be no actual temperature control.  The 'controller' appears to be a simple 'simmerstat', which, like an older type electric hob, simply regulates the average power fed to the heater, usually as an arrangement where one of the  power contacts is attached to a bi-metallic strip which will bend as the temperature changes (while current flows through it), regularly disconnecting and reconnecting the power, the average power roughly, but fairly consistently, determined by the dial setting.  

They have an over-centre arrangement so the power is disconnected and reconnected abruptly, avoiding surface burning on the contacts and, by design, have a hysteresis period set by the approximate rate of cooling (strip straightens) until the contacts click closed again.

RAB

Beansprout

#5
I think I understand that :D So instead of reaching the temperature like an oven, it monitors the power going in and balances it taking into account the heat lost from the door? Is that why they want to keep the door open, as the heat has no where to escape, and the power will carry on being fed into the kiln?

I might  get a multimeter with a K type thermocouple (wire one) to tuck into the door to have a look at the temp, as an experiment :D

I also need to figure out a way to fashion a bead rack to fit inside...

flame n fuse

you can make a bead rack out of a Z shaped piece of bendy stainless steel mesh, standing on its side and resting the mandrel tips in gaps in the mesh

Moira HFG

That looks like the controller on my Quikfire. It's not a proper temp control, it just controls speed of heating, like the knob on an electric hob.
But if you can get a thermocouple in it to see what temperature it's at, you'll soon find what setting you need to keep it ticking over. Just start by running it empty until you're confident you can anneal successfully, and not slump!

(Mine I run at half power to annealing temp, then turn it to low for the time I want. For fusing I use full power, then low-to-medium to maintain it).

oliver90owner

balances it taking into account the heat lost from the door?

Again, not quite.  The power going in will be controlled by the simmerstat, so the temperature will simply change until an equilibrium situation arises (as much heat lost as gained); leaving the door ajar will simply increase the amount of heat lost, so lower the temperature for any given setting.  The effect will be a lower temperature than otherwise, of course, but with no real control - a bit like opening the windows if the central heating is too high, rather than turning down the thermostat!  The kiln would likely only overheat if left closed and on a high simmerstat setting.

A K-type thermocouple is a good reliable option if kept away from the refractory.  An alternative to a multimeter and K type thermocouple might be one of the IR/colour pyrometers - there are some 'relatively low' cost (still far more costly and less 'general pupose' than a multimeter) items available these days - unfortunately mostly for lower temperature ranges; not necessarily accurate but fairly reproducible results, so need a bit of calibrating.

RAB

Redhotsal

Unfortunately, I think you are going to struggle to get this kiln to anneal beads for you. It was made as an enamelling kiln, so the aim was to get to a temperature and then to get back down again in a not very sophisticated manner. Basically, you will be able to attach something to control the kiln temperature, but you will have to do this by hand, i.e. literally turning a knob down at every few degrees - like an oven. O.k. - not to be pendantic - like an oven in the sense that you'll have to turn it up and down. You're going to have to somehow get it up to 520C and then "ramp" it by hand (ideally at 1 degree per minute) until you get down to something approaching room temperature. Life is frankly too short to mess around like that. You'll have more fun sticking blunt mandrels in your eyes.
The Uhlig is a very similar shape to Kilncare's BeadCube, but is not at all similar as the BeadCube does have very comprehensive temperature control. I'd be inclined to save up until you can afford something with an electronic controller, as throwing money at this kiln probably won't be worth it.  :(

Nicknack

I'm afraid I agree with Sal.  Why not just try some enameling in it?  It's still glass, the results are more instant, and also can be very pretty.

Nick

Stackmyra

Or you could just buy a PID controller with ramp and soak on ebay, a Relay or a solid state relay and a type K thermocouple capable up to 1200 degrees C, and a input contact for 230v and a wall contact for the oven and a on/off switch

then drill a hole in the back of the kiln and install the thermocouple, just be careful not to drill through the kiln element, that would be irreparable. then build a small box and install the PID regulator, the 230v input contact, power switch and the wall contact and wire it all together.

then you need to change the oven door to something thicker to hold the heat, this is not a big kiln so it will not hold heat well, when you change the door you can build a bead door if you want, just attach a kiln brick 2cm up from the bottom and then attach one on the door leaving a 5mm slot between the bricks, you have to cut off half the existing door.

Its not that hard, I have done it with a similar kiln. And it works perfectly

the kiln itself will live a easier life as a annealing kiln then a enamel kiln, the temperature will often just be half that of a enamel cycle.

Lee - Kilncare

#12
Oooh I have been lapse over the Xmas period with regards to my FH duties :o(

The kiln is indeed a Uhlig U5. A sister kiln if you like to the EFCO 110 and in a perverse kind of way, related to the Bead Cube....ish.

Forget annealing beads in it in its present state.....not a prayer.

Simple, to anneal properly you are going to need to read the temperature and to be bang on, you will need a programmer. You can search for one or there is one here that is made for the job of controlling that kind of kiln without any additional wiring.
http://www.kilncare.co.uk/kilns_controls_controllers_kcr1plugincontrol.html

Two things I have picked up on with previous posts.
Infrad red thermometers are not too accurate when it comes to kilns as they read the temperature of the surface they "touch" and that can vary considerably from the ambient of the kiln believe it or not. The reflection of refractory can often upset IR devices.
Secondly, depending of the age of that kiln it may well have an asbestos content in the insulation so be carefull if deciding to drill it for the thermocouple.ike I say, it may have, it may not, certainly EFCO don't reccommend messing with old insulation of theirs for that reason.

As has been rightly pointed out, you regulator simply operates on time to avoid complicating maters. Think of it like this. If it is set for half way, the kiln will come on for say 15 secs then go off for 15 sec etc/ At 3/4 it will be on for 20 seconds and off for 10 etc/ Thats how it works. Simples.

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Beansprout

Thanks everyone for your very helpful replies!

Oli, thanks for the in-depth techy talk! Sal, I think you're right, My optimism is much larger than this kiln obviously! (I have a few blunt mandrels set aside for when the moment takes me)

Stackmyra, I have been lent this from a friend and he wants it back eventually so I don't think he'd be too happy if I started drilling holes in it! That project is something my Dad would be OK with doing but me, no way in hell!!

Lee, of course, thank you! That little controller does look very useful indeed however I don't want to start spending money as Sal said, when I could save for a proper little Beadcube! AND the little description of the regulator has made the most sense, ta :D

I can;t find the quote now but who ever said they had'have the same regulator, which way round is "hotter" or "colder"? I reckoned 11-12'o'clock gave the highest/quickest heat, then 6 o'clock started to decrease in temp..

I fired it up this afternoon with a broken ceramic thermocouple and a very old pyrometer... who knows if that measurement was correct... but I could see it going up and down. The temp it's showing there is 600 degrees C  (I think it is C)




Beansprout

We bought a small ceramic kiln (much larger than this one) a few years ago and it came with a controller- it's currently residing in a box in my dad's house so I couldn't tell you the make but he says he hasn't got a Relay... So once he wires that up and sticks the pyrometer/thermocouple on it (from the pic) we should be able to anneal some beads!!