jewellers muffle kiln

[Zia]

Second hand kilns are almost impossible to buy here.....so I have a question...

Can you use a jewellers muffle kiln to anneal lampwork beads?

thanks

[Zeldazog]

The main difference between a jewellers muffle and a "normal" kiln is the controller.

As far as I know, muffle kilns usually just have a dial that you can alter how fast they heat up - low to high, etc.  I think some people just go by the colour that they go to, although you can get a pyrometer which will give a temperature read out.  Once you get used to your kiln, you know when to turn down the dial, so that you have control over the heat rate and can get it to hold.

Probably the most important aspect of annealing, is not just the holding so that you even out the temperature within the bead, etc, is controlling the cool down rate to the lower strain point.

It can be done, but you have to be prepared to kiln sit, in other words watch over your kiln so that you can control the hold temperature (well, you'd be there beading anyway), but to keep watch whilst it cools down, so that the temperature doesn't drop too quickly.

Kilncare's Bead Cube is essentially the same as a jewellers muffle kiln but with the added extra of a controller to do this for you.

Hope this helps

Dawn
x

[Zia]

Thank you

so if I understand you correctly......

If I get a muffle kiln with a controller....it would do the trick?

another question...

would you (with your experience!) :-) prefer a muffle kiln or a potters kiln(batch annealing) for bead annealing

these seem to be the only types of kilns second hand on the market here....

thanks for your answer......

[Zeldazog]

Zia

When I was first looking for a fusing kiln, I was looking at these, because of the price.  However, I never came across one that had a fully programmable controller.  They only ever had a pyrometer and dial temperature controller.

I know I saw that you could buy a programmable controller for at least one of the popular muffle kilns (probably a Uhlig) a couple of years ago - but the cost of these on their own is quite high, and I know that and the kiln together came to more than what I could buy a kiln with a built in controller for.  Even second hand controllers go for decent money and many ceramics ones don't have a ramp down.

Now, with a ceramics kiln, which is lined with firebrick, this is less of an issue - firebricks are very good insulation hold the heat very well and so long as they are left closed, they usually cool down at a slow enough rate for safe annealing.  My first year of fusing was ALL done in a ceramics kiln with no ramp down control (so only the kiln's natural cooling rate) and things are still alive and well 3 years later.

Muffle kilns are usually lined with ceramic fibre, which doesn't insulate quite so well, I don't know if they cool too fast or not.

I don't make beads, Zia, so I can't answer your question about muffle vs potters kiln, other than the comment above that a potters kiln cools slowly.

HTH

[Zia]

smiles, but you do make beautiful works of art!

thank you for your answer.....

xxx

[Zeldazog]

smiles, but you do make beautiful works of art!

thank you for your answer.....

xxx

Aw, thanks! 

[Trudi]

also I beleive that the controllers are a big part of the cost of a kiln!

[Zeldazog]

Indeed they are Trudi, a quick look on Kilncare and couple of other sites, and those that are suitable for glass (which ideally needs at least four segments, best five, for fusing, with the facility to ramp down (not all ceramics kilns have that as feature) - £200 plus.

I remember when I was looking at the Caldera, they sell a non-digital version, with an infinite switch controller (that was the word I was looking for earlier) - and I think that was around £200 cheaper than the fully controlled version.  Other than that, same kiln I think.

But I suppose the controller is a complicated bit of kit.  Afterall, it's not as straightforward as, say an oven, where you tell it what temperature to get to, and it stops when it gets there, heating up again if needed. 

A kiln controller not only has to know when its reached a temperature, but how fast to get there and how to adjust slower and faster, etc.  Clever little things really!

[Lee - Kilncare]

Well with respects to the batch annealing in a ceramics kiln, you may find that you can only batch anneal in a muffle kiln due to the door not allowing mandrel space. Unless you do some kiln butchering or some other clever method of sealing up an half open door.

As Zeld says, the Bead Cube is essentially a muffle kiln with a modified door, making it ideal for garaging and correct again, the controller is a large part of the cost.

The KCR1 which fits to the Bead Cube and MAXI will fire any 3kw plug in kiln. It is primarily for temperatures below 1100c but can be adapted to go higher but you want to be going anywhere near there.

Oh and again Zeld is bang on, a muffle kiln will naturally cool quicker  than a brick kiln, certainly a ceramics one that can have walls of up to 5-6" thick. This is where the controller comes in.

Hope you get sorted O.K.

Lee

[GoodMonkey]

Oh she's good that Zeldazog 

[Zia]

uh huh, wonders why you lot havent convinced her to try out beadmaking though....

[Zeldazog]

uh huh, wonders why you lot havent convinced her to try out beadmaking though....

Not for want of trying!  They *MAKE* me go on a torch when I am near one.....

[Zia]

lmao.....would love to see a pic of that....I think the girls here can be pretty convincing

xxx

[Zeldazog]

It's not that I don't want to do it, Zia. 

It's kinda like this - I get "mardy" if I can't do something well, and think that I don't like it.  I know I need to make more than three beads to get good at it.  So I know I need to spend time doing it.  I know that if I spend a little time doing it, and start to make stuff that I am even vaguely proud of, then I will like it.  I know that if I like it, I will want to do it all the time (see card making supplies, enough to stock a shop, and I am trying to match Warm Glass for stock of Bullseye sheet glass!).

So, I *think* that the reason I wasn't totally and utterly enamoured after my first go at the torch a couple of months back, is because in the back of my mind, I know that I can't, not yet - I need to concentrate on that last year of my degree.

And I haven't got space.  I NEED a workshop for my glass fusing, and I am already contemplating how big I would need to house a torch set up as well as (of course) an even bigger fusing kiln, and some ceramics.... then a bit of a woodworking area to make the frames etc for my ceramic wall art.....


Not sure how much longer I can hold off with the torch now that dear son is totally hooked on it though.....