I'm having a bit of a nightmare with pandora in my new shiny pink kiln. Its proving very hit & miss to get the beautiful purples and greens - the colours come out in the kiln but, on some beads only, they fade to creamy green during the annealing cycle.
I'm convinced its my kiln cycle - which worked perfectly for the SC2 - is anyone getting good results from Pandora in their Maxi and Maxine and willing to share their cycle please?
It will help preserve what little of my sanity I have left ???
Thanks
Sarah
ME TOO!!!
I've blinking well got an order too for Pandora beads!
The first lot I got I left at the left hand side of the kiln and I got the weirdest salmon pink colour. So I re-did another set as I thought it was a fluke and I got Pandora Green Beige. I reanealled these and they didn't change and the THIRD lot I did I used a very thin layer of Pandora (which seems to work usually) and put them at the right hand side of the kiln and removed the lower shelf.
These came out a bit better - i.e. ONE of them is the deepest most gorgeous purple but the others were very pale and greeny cream too.
I'm convinced it's all down to kiln temp and yet I got lovely results every time with my Bluebird. I think all kilns must vary in terms of what the temperature actually IS compared to what the controller says the temp is so I'm going to take the third set and soak them at around 490 degrees for a few hours in my big kiln and see if anything happens. Then, if that doesn't work I'm going to soak them at 540. Then, if that doesn't work I'm going to soak myself in red wine..........
Keep in touch - we need to crack this dilemna
Thanks Sal - I'm convinced its kiln temp too. I'm soaking at 510 and then giving an hour on 520 which worked well in my SC2.
I find the beads with the deepest purples come from the far right hand side of the kiln in the bottom corner. I notice that the controller shows a bigger temp drop on this side than on the left hand side when you open the bead door. So I'd assumed that this is where the thermostat sensor is. Not sure how relevant that is 'though as I think that the element is in the roof.
The further left the beads are the creamier they come out - and like you I get the salmon pink from long annealing. Some of the posts in the Pandora thread on LE recommend soaking at 1000F so I was going to try going up to 540 next - let me know how you get on.
I had to be forcibly prevented from putting the rest of my pandora stash in the recycling box this afternoon.....
Sarah
xxx
>:( That's annoying, isn't it? Have you tried using potters' cones to test
the temp in different parts of the kilns?
Marg x
thought about it but seems too much of a faff. We just need to hit on the right temp. will fiddle some more until we solve it. It's a bother as I have a "live" order, but oh well......
I agree Sal - 'though my gadget loving other half has recommended an infra red thermometer :) That sounds like fun!
I have just taken out a small batch with exactly the same issues - the bottom right is definitely the place to be. I'm about to re-fire some of them at 530 and will let you know how I get on. Unless I get to the red wine soaking stage first.....
Sarah
xxx
I'd be interested to find out too ladies, as I was thinking about getting hold of some Pandora, but not going to bother if it turns out rubbish like a lot of my other attempts at silver glasses.
Has anyone PMd Lee for tips yet?
Sarah,
Oh dear, and now I've got your kiln that worked so well. If you can bear to batch anneal you're more than welcome to bring your beads over and do them in your old kiln.
Not sure Collette would agree - she has just bought my Bluebird which would probably produce the most glorious Pandora beads if it wasn't busy blowing all the fuses in her house! :o
It's another factor in the old what-works-for-one-person-doesn't-work-for-another regime. There was a post on here recently concerning Pandora and how difficult it was to get the purple colours. I just didn't get it at all - every time I did Pandora it always came out gloriously purple and wonderful. as soon as I change the kiln I just get green-beige. Hmmmm....frustrating but I reckon we can solve it. Or, there'll be a batch of oddly coloured beads lying in an unmarked grave in Hinckley in a few days time! ;D
I think that post was mine Sal!
I've now run out of Pandora and don't plan to buy any more. I had success - and disaster - right in the middle of my Maxi. :(
Ahhhh, I may be able to shed light on your Pandora problems.
When I got my Maxine I spent a very geeky 3 or 4 hours getting Rick to check how it ran, you know, does it have hot spots, is one side hotter than the other.
I was supposed to send my results to Lee and haven't got around to it yet, but I know exactly how mine runs. We checked the temperature using a thermocouple attached to a meter. I have a little diagram somewhere with the results and an annealing schedule to cope with our findings.
Now....where did I put the beer mat with the diagram on?
Quote from: Sarah on January 18, 2009, 06:11:02 PM
I have just taken out a small batch with exactly the same issues - the bottom right is definitely the place to be.
Sarah
xxx
Bottom right is the coolest spot, centre is the hottest, and bottom left is about 20 degC (I think or maybe it was 15degC) hotter than the bottom right, if I remember correctly.
At least I should say this is how my kiln runs.
Quote from: silverlemon on January 19, 2009, 01:14:03 AM
Now....where did I put the beer mat with the diagram on?
Ah, glad to see someone else as articulate about their paperwork/record keeping as I am ;)
Hmmm, although I just anneal for strain relief and not colour the temp of ovens is interesting. Mine is 20 years old and top back is hottest. Logically if one belives hot air rises. I have annealed soft glass at very fornt of oven and Boro at back top, all at same temperature and with stress free results. Only way to get uniform temp is with an internal fan and some ovens have this but they tend to be larg ones and one need sto be careful with vibrations set up with elements and fan. I still remember how much fun it was to put a delicate coiled glass item in oven and to hear it shatter as temp rose and fan sped up!
Ian
Heh!
Well the result are in from Leicestershire:
Held the beads (ones that had been made earlier) at a few hours at 480 going on the basis that the bottom right is indeed cooler than anywhere else and yet that's where the best results were to be found.
No change.
Then ramped the beads up to 540 to try and gee 'em up a bit and held there for a few hours.
No change either.
I've got a feeling that it's really hard to strike Pandora again once it's been struck and encased.
It would imply that you need to make the beads and strike at a lower temperature rather than a higher temperature? Nearer 500 perhaps - so that the bottom right hand corner gets even cooler? This is the theory but whether it works in practice I dunno!
B()($&(*£" Pandora..... >:(
As Sarah (silverlemon) said I spent the best part of a whole evening ramping her new kiln up and down and holding it at various temperatures all the time watching and measuring the temperature at every point along the kiln's length. (yes I'm a geek)
From this information I have set the anneal temperature so that the majority of the kiln is within the anneal range for the glass Sarah is working with.
The kiln also exhibits quite an overshoot after you open the door if you are not careful with your anneal temp.
As Sarah said... we will need to dig out the "fag packet"/"Beer mat" that the results were scribbled on !!! ;)
Quote from: Dickie on January 19, 2009, 10:03:54 AM
As Sarah (silverlemon) said I spent the best part of a whole evening ramping her new kiln up and down and holding it at various temperatures all the time watching and measuring the temperature at every point along the kiln's length. (yes I'm a geek)
ha ha ha, he didn't want to spend time doing this but I made him! who'se the bigger geek? :D
Quote from: Dickie on January 19, 2009, 10:03:54 AM
The kiln also exhibits quite an overshoot after you open the door if you are not careful with your anneal temp.
To be fair you only get this on the Maxi if you keep the door open too long, like I used to when rearranging mandrels in my old kiln, but I don't have that problem now with all the lovely space in my new Maxine :)
I'm grateful for your geekery Dickie & Sarah :)
My run at 530 has resulted in the pinkie overstrike colour and is worse the further left the beads were.
So I'll knock it down to 490 next time, try that & work up frm there. I'll have to do some research before I put any TNT2 in there as that needs a lower temp too.
And Helen - that's very kind - but hopefully we'll suss this & you won't have me standing on your doorstep over the weekend :-* :-* :-*
Thanks again - and I'll let you know how I get on
Sarah
xxx
Hi All,
I can't believe that there will be much difference between one Maxine and another. So given that here is the schedule Sarah uses for
most types of glass... hope it helps.
- Full to 465 degC hold for 20 hour (Garaging)
- Full to 483 degC hold for 1 hour (Annealing)
- 60 deg/hr to 320 degC hold 0 (Ramp down)
- Off (Switch off)
Now... I'm sure you're all thinking... 483 degC... that's not hot enough to anneal... well yes you are right... but... (keep reading)
The thermocouple in the kiln is in the far right hand corner, and this is the coldest point in the kiln.
When the sensor reads 483 degC then the hottest point (center top) will be at 524 degC (and a gradient in between)
A point to note... we have anneal tested transparent beads (from this annealing schedule) from right hand end using polarising filters and they were fine... so I would suggest this schedule to anyone with a Maxine.
Hope this helps
Dickie and Sarah,
Wow.....I'm so impressed with your thermocoupling skills!
It would make sense. Horrible salmony pink colours can be obtained from the left of the kiln and more purple (but not quite the right purple colours) are found at the cooler right hand end. But the right hand end is still too hot.
I'm going for fourth time lucky on Pandora today so I'm going to take the temp down a bit and see what transpires.
Really - thanks for all the helpful advice on here. We ought to start some kind of Maxine Owners Club!
Thanks Sal...
Basically everyone should check their kiln temperature, all kilns are different, and will have temperature gradients (unless they are fanned, and even then there will be differences).
The chances are if you are setting your kiln temperatures directly from the datasheets for the glass you are using, then it will probably be wrong for many places in the kiln.
We have carefully set the anneal temp (to 483 degC) so that over the majority of the kiln's width the temperature is within the annealing range of 493-520 I think, for effetre (that's off the top of my head don't quote me on it) . If we had just set the kiln to anneal at 510 or 505 or whatever then MOST of the kiln would have been WAY too hot.
My brain has turned to porridge just reading this lot - I think I will just have to stick with the 3 programmes that Lee input into my Maxine as I don't seem to be having any problems (so far ;D) and am avoiding Pandora like the plague although it used to be my call sign when I was very young and into CB radio!!!
Kazx
Quote from: Kaz on January 20, 2009, 10:51:44 AM
My brain has turned to porridge just reading this lot - I think I will just have to stick with the 3 programmes that Lee input into my Maxine as I don't seem to be having any problems (so far ;D) and am avoiding Pandora like the plaque although it used to be my call sign when I was very young and into CB radio!!!
Kazx
Hey Pandora, what's your twenty? 10-10, we'll do it again!!
Quote from: Dee Dee on January 20, 2009, 10:49:37 PM
Quote from: Kaz on January 20, 2009, 10:51:44 AM
My brain has turned to porridge just reading this lot - I think I will just have to stick with the 3 programmes that Lee input into my Maxine as I don't seem to be having any problems (so far ;D) and am avoiding Pandora like the plaque although it used to be my call sign when I was very young and into CB radio!!!
Kazx
Hey Pandora, what's your twenty? 10-10, we'll do it again!!
Eyeball, eyeball - but not til later in the year Steph! ;D ;D
Yup, and that's when I fell off - it all made sense up to now ::)
:D :D :D
Hi Dickie and Sarah - Thanks for posting this info, it is so nice of you to share this information and help others.
I love this forum
;-)
O.K. flamers!!!!!!! In true tradition we have been monitoring this temperature variation issue.
With a kiln of this design we would expect a hot middle section but there are some quite extreme readings on here.
We have tweaked, changed and messed around with many solutions. Believe it or not, the first one we tried and the most simple, gave the best results and it was as follows.
It is very technical, not, simply, bend the end of you thermocouple upwards until it is around 10mm below the element. That's it.
The results here on 3 different MAXIs have all been very similar and they are as follows.
With the sensors we used, placed in the second holes up in the rear grill they gave, with the controller holding at 520c:
Right side 500c
Left side 507c
Centre 530c
Now quite why the variation should have pulled in by this simple mod is a bit of a mystery, we were expecting the variation to remain and just the temperatures to alter. I must be the leveling effect of heat loss.
Anyway, Red Hot Sal has tried the MAXIs out again for us with a couple of types of glass and under the polarizer, as Dickie says, the results were just fine.
I have also just had a rattle with Claire and she too is so far happy with the results.
All new MAXIs will go out with this modification.
If it is that you want to alter yours it is so simple to do, then again, you may now be used to the characteristics of your MAXI as it is.
Don't hesitate to reply or pm me if you have any further issues regarding this.
Thanks Lee :) I'll be trying that mod tonight. I have got used to my Maxine, but I think I'd prefer her to be running as sweetly as possible.
So when you say bend the end of the thermocouple - do you mean just with a pair of pliers through the open door whilst the kiln is unplugged? Nothing more taxing than that? Just checking because I don't want to start something I can't finish and I'm no engineer :)
Any chance you or someone could post a pic of the modified bit to make sure we know what we are doing?
Sorry, I'm probably being a bit (?!!) thick, but I don't want to take any chances with my beloved Maxine!!
xx
Here you go, as for how to do it.
The thermocouple is actually easy to bend and not too stiff.
The one here was actually bent whilst the kiln was holding 520c and I used a long screwdriver to apply pressure upwards.
It may be better to let it cool and gently push the end of the thermocouple upwards with your finger, it is that easy.
(http://i133.photobucket.com/albums/q73/shiffa_2006/13052009875.gif)
Oh yes, this is only optional, but you may tie it in a degree or two further if you remove the side cover, slacken the thermocouple retaining screw and fully insert the thermocouple into the kiln before re-tightening the retaining screw. MAKE sure the kiln is unplugged first.
When the kiln was originally assembled the thermocouples were left about 10mm short of being fully inserted.
As I say, this step is not really needed and the job will be fine if you choose to just bend the thermocouple as described at the start of this post.