Lilya

@Babs Thank you again. I'd love to buy a kiln with more functionality one day, but at the moment, that's what I have. (It is wonderful though!) As for dunking, thank you, but I've tried that already and didn't have any luck. Someone else actually recommended to me that I bisque lower, so I guess it's worth trying whatever I can!

@Babs Thank you again. My kiln's max temp is 1020°, so while I could go a bit higher, I couldn't get to cone 04. I'll see what happens though, thank you.

@Min Brilliant, thank you. I'll try that! I've also been trying a GB : neph sy 50:50 mix with the dodgy GB I have. I was hoping that reducing the concentration might help to reduce the bubbling, etc. It's not perfect, but it is better. I do know that GB is not a forever option, but it might buy me some time to get a real replacement sorted. Many thanks again anyway :-)

@Babs Thank you for your reply. My original post was about alk frit + neph sy, but I haven't used it since then apart from on a project where I really wanted its rough, patchy look. I've been using frit 1254 + kaolin more recently ... that's what I added the CMC gum too and it's that I'm now struggling to brush. I wonder would glycerine work there? But for the alk frit + neph sy (+ bentonite), for that I was using a pre-mixed gum blend that I added to water. The whole mix would separate literally instantly. I was mixing it in the bottle, mixing it in the dish, watching it separate on the brush, etc. I thought about what else I could add, but after my first post, Neil said that it was too far gone to save, so I sort of gave up on it. I almost threw it away actually, but I kept it (and shake it every few days ha!) because there are certain projects where I like its look as I said. Even if it is a nightmare to apply! But I had read about Epsom salts, so maybe that would be worth trying?? Or more bentonite to help with suspension? I bisque to 980°. The clay's temps are 980 – 1300°C ... it's white at lower temps but turns grey higher. My main problems overall are brushability and flow, but with the alk frit + neph sy, it was the separation too. In reality, I wouldn't use the alk frit + neph sy on a regular basis anyway as it's a bit too opaque, but it would be nice to get it working better for when I do need it. Thank you again!

@PeterH Just CMC (+ copper carb), yes.

@Babs Ok, thank you very much! I'll try that. @neilestrick It wasn't very syrupy, no. Just like very slightly slimy water. I mixed with the proportions given, but maybe it wasn't enough? Veegum T would not appear to be available here. I've tried it with first layer wet, first layer touch dry, first layer actually dry: each has its own problems. But I'll try another batch of CMC and see what happens. Thank you both again.

@Babs Thank you for your reply. The pieces are clean — no dust — and I have tried the glaze with various amounts of liquid. It seems that this mix just doesn't want to flow very well. (It is frit 1254 : kaolin, 90:10 or 85:15 so far.) CMC needs to be cooked? The instructions I have don't mention cooking. How do you cook it please? Thank you again.

Hello again kind people (and no worries if you're too busy for yet another question from me!!), I'm still experimenting with proportions and temperatures, but in the meantime, I have another problem: the glaze I made at the week-end was much worse last night than it was first time around in terms of brushability. I made up a big bottle of CMC gum + copper carb. that I've been using to replace 1/3 of the water in the recipes, but whereas the first time I used it, it worked well enough, subsequent uses are increasingly less useable. Argh! The first layer goes on fine, but the second layer jumps over the first when I try to brush it on. The third is even worse. And it can't stand texture. I've taken to *always* filling in textures (all my test tiles have simple faces or patterns now ha!) first with a tiny brush to try to avoid black holes, but then I'm getting depressions where the following layers of glaze won't sit nicely on the original. I've tried it thick and thin and everything in between. I try to smooth it all over in between layers and at the end, but I inevitably miss something and end up with holes, because the glaze doesn't seem to flow and fill in. Maybe I'll find a proportion that does, but I'm not there yet. Maybe I'll find a temp that works better too, but at the moment I feel like I'm shooting in the dark even when I'm looking! My last opening was at 980° ... everything was nicely melted, but I could see the holes in a piece even then. I let it go till 1000° and held it there a bit, but the holes persisted. No more appeared, but the ones that were there didn't go either. My kiln only goes to something like 1020°, so really I'm fairly limited with going much hotter. (And yes, I would love something with more functionality eventually, but that's all I could afford at the time! And to its credit, it has been absolutely brilliant and allowed me to do what I love.) So I'm wondering if the gum has gone bad so quickly? And if I'm just chasing rainbows trying to get a non-GB, brushable raku glaze with what I can get here in France? Thank you all so much again for your help. Whether you answer or not, I really do appreciate all the info you've given me so far.

@Bill Kielb Thank you again for the explanation. I'll do some tests soon then and see what happens!

@neilestrick Ok, I'll look into that (no pun intended)!

@Bill Kielb No worries at all. Thank you very much for the clarification and explanation. I'll make up another batch of test tiles and some mini glazes mixes of varying proportions and see what happens. More economical is definitely a good thing! My only concern / question, and this could be totally down to my ignorance, is will more alumina make the glaze stiffer / flow less well when it melts? I'm already finding that I don't have as much flow as I did with the GB; this is an issue for me given the carvings, etc., on my pieces. If more Al will reduce the flow even more, it probably won't work for me (but I will give it a try just to see). But if I'm just being dim and it doesn't work that way, then yes it could be good to have more kaolin. Many thanks again.

@neilestrick @Min Thank you both. Basically it's a big cube ... it's hinged near the bottom, so the whole top lifts off — the bulk of the cube — to leave a square, er, firing platform. So I suppose if I lay on the ground level-ish with the base of the kiln (at a safe distance!) and my husband started to open it, I could see what was happening without actually letting a rush of air in. Otherwise I could just try to open and close really fast. Maybe the next time I do my test tiles, because then it won't matter too much if something goes awry. Thanks so much again.

@neilestrick Nope, no way to see in without opening it. It does regain heat pretty fast once it's closed again, but I'm still thinking it wouldn't be great to lower the temp so fast (through opening) and then have to re-raise? Thank you again.

@Bill Kielb I'm sorry to bother you again, but my brain has just caught up with the maths. You said "So 75% /15% may be worth a try ...", but that's only 90; am I not understanding something, or should it be 85/15 or 75/25? Thank you so much again for your help!

@neilestrick Thank you so much again for your help. Unfortunately, I can't watch the melt as my kiln is electric (French: it's made for bisque and raku), so I can't open it to see w/o massive heat loss. But hopefully I'm getting somewhere now ... we shall see! Many thanks again.

@Min Just an update (I hope you're having a lovely Sunday): I tried 1254+kaolin and FR8+kaolin this afternoon and the results are pretty good! Consistent, glossy finish on both at 1000°C ... slightly more teeny teeny tiny micropits with the FR8, but both are definitely a huge improvement over what I've seen so far with other mixes. The 1254 seems better in general and was easier to brush on, but the difference is marginal. Neither flowed into carvings as well as the GB and I did get some black holes, but they were only over the smaller carved areas. For the bigger ones, like my roman numerals to mark the tiles, everything looks as it should. I'm going to try again (when my next batch of test tiles has been fired!) and pay special attention to filling in carved areas first. This time I just wanted to see what happened if I brushed as I would've before. I'll aslo try the 1254/FR8 blend and the 75:15 ratio that @Bill Kielb suggested. So massive massive thanks again to you and to Bill. I'm feeling quite relieved that I'm getting somewhere! :-)

@Bill Kielb Ok, thank you so much. I'll see what happens ... I'm not using EPK (can't get it here) but another kaolin; I realise now that that in itself may be affecting things. (As an aside, I'm going to try pit firing soon partly because I want to experiment and it's my compensation for not having a wood-fired kiln, but also because it might be a nice mini break from glazes.) Thank you lots for the Sue McLeod link. I've seen a couple of her YouTube videos actually and marked her as someone to look up but hadn't got to it yet. It's good to know that she's recommended; I'll check out her site. Many thanks again!

@Hulk Thank you very much for the explanation and the link. I realise I have a very long way to go, but I'm grateful that I'm starting to understand things a bit more. So I'll be depending on Boron quite a lot then, given my low temps!

@Min Oh my goodness thank you so much. I am beyond grateful, thank you thank you. And yes, the colours of the program are hideous but seeing everything there side by side helps an enormous amount, whatever colours they are. Thank you. So having looked some things up, would I be correct in thinking (roughly) that silica and alumina kind of act the opposite to boron? I know I'm hugely oversimplifying here, but yes: boron melts, they stiffen. So looking at those, the 1254 mix is higher in Si and Al than the FR8 mix, but it's also higher in B which might make up for that? Anyway I will try all of these and see what happens, thank you so so much. My last resort was going to be ordering another batch of GB from a different supplier, praying, and then ordering loads if it works (enough to keep me going while I try more alternatives), but fingers crossed something will work here. Honestly, thank you _/\_

@Bill Kielb Thank you again. I was using 80% GB : 20% neph sy., either plain or with added pigments / oxides. It worked really well until I got a bad batch of GB that bubbled, fizzed, pitted, cratered ... it was then I started learning about the many joys of GB and why I should change recipes asap! As I said in my original post, I struggle with the chemistry due to brain inflammation from illness (autoimmune, nervous system dysfunction, etc.), and although I am trying to grasp it all, it just isn't sinking in. My first attempt was 85:15 alkali frit / neph sy (I also tried alk frit : kaolin, but it wasn't as nice). It was fine for dipping but terrible for brushing, it bubbled up over texture when I tried to apply it, and it separated within seconds. I tried remaking it with gum and bentonite, but I just couldn't get decent results. At least not consistently, and it was still desperate to separate. So I decided to ask here, and Neil kindly recommended the 90:10 3124 and kaolin recipe, but as I can't get 3124 in France, things got tricky! I'm going to try a mix of 90:10 1254 and kaolin this afternoon ... 1254 is only available in France I think, but it's apparently formulated for raku and I know someone has had success with it at that ratio. I might try it also at 100% 1254, just to see what happens. Beyond that though, the most readily available frits seem to be 3110, 3134, 3195, FMTR101, 1249–1257 (Ceradel), and FR1–12, FR413, FR644 (Solargil). There are a few other suppliers, but their stock levels seem less consistent and they're pretty much just stocking the above mentioned anyway. Essentially, I'm looking for a transparent raku glaze that is or can be made brushable. One that looks nice on its own but that is also happy to take colours. My work tends to have texture or carvings in it as well, so something that flows relatively well when wet is essential, as otherwise I end up with black gaps over any kind of texture no matter how diligent I think I've been with a tiny brush. I guess I was spoiled with the GB. Many thanks again to your for your participation on my glaze quest! Ps - 1254 is formulated as follows: Analyse Chimique : SiO2 : 30-60% / Al2O3 : 5-10% / B2O3 : 10-30% / CaO : 1-5% / BaO : 1-5% / ZnO : 1-5% Na2O : 10-30% / K2O : 0.1-1% Formule moléculaire : Na2o =11.2 Cao = 10.2 Al2o3 =7.4 B2o3 =27.7 Sio2 = 43.5

@Bill Kielb Thank you for your reply. I didn't, because the 3124 substitution recipes I was using came from Glazy. So I just mixed up according to the proportions given there and then added kaolin to make the 90/10 mix that Neil mentioned in the beginning. I did get some melt — there are some shiny patches — but certainly not a consistent finish!

@neilestrick Thank you, raku fired to 985°C ... I usually go to 1000° with the GB / neph sy mix, but as the temp on the FR8 was stated as 850-1000, and from what I could find, the 3134 mix was 950+, I thought I'd hedge my bets. I wouldn't have been surprised if one failed, but for them both to fail in the same way ... I'm now wondering whether I mixed wrong or if it was the kaolin? I spent last night trying to compare formulae, etc., to work it out. Thank you again.

Hi again @neilestrick , I hope you're well. No worries at all if you don't have time to answer, but I've tried the French substitution recipe on Glazy for 3124 (both versions: the one with 3134 and the one with FR8) and the results are very depressing. I made up two batches of glaze that were identical apart from the frit (3124 sub. + 10% kaolin + CMC gum solution (1/3 of water)) ... one was more brushable than the other, but both fired to a horribly rough, lumpy texture. Both look like they just haven't melted / vitrified properly. There are bumps, a few pits ... it looks grainy too. They're essentially the same even though one is 3134 and the other is FR8, so I'm thinking that maybe the substitution recipe wasn't great? (Thus far I can't find Pemco or O-Hommel here, but I'm still looking.) Is there anything that jumps out at you as to why these glazes woudn't have worked? Again, no worries at all if not. Many thanks again. Take care and have a good week-end.

@neilestrick Brilliant, thank you heaps!

Hi @neilestrick, thank you so much for your reply. I can't find frit 3124 here; I've already looked and it doesn't seem to exist in Europe. I'll check again though. I know it's sold in the UK, but since Brexit, importing onto the continent is a nightmare. Is there a substitute, do you know? For the gum, I was using a Ceradel label gum. 20g of gum:1000ml of water, left overnight. Then 850g of that solution to 1kg of dry glaze base ingredients (not including and colours), sieve, and add extra water to make the consistency like crêpe batter (France!). It's better than when I didn't use the gum at all — that was totally unbrushable — but it's definitely not great. The label doesn't specify whether it's CMC, but I've just seen that they do also sell pure CMC, albeit at a much higher price, so I'll try that next with the copper carbonate. Thank you so so much.