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nancylee

B-Mix And Me - A Contentious Relationship

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Morning,

I have long had a contentious relationship with B-Mix, Cone 5. When making mugs, more often than not the handles crack, pull away or fall off. When putting any kind of surface decoration onto the piece, it cracks, pulls away, or falls off. I've dried it naturally and slowly, with a dryer and a torch - they still fall off more often than not. I've used this "magic water" at class, slip, water, scratched the daylights out of it - they still often fall off. 

 

Last week, I picked up a still pretty wet urn about 7 or 8 inches tall I had thrown from the studio where I still take classes. I had thrown it two weeks earlier. It was B Mix, which is the only white at the studio. I let it sit out for a morning, dried it a bit, trimmed it, dried it a bit more with a dryer, and put it in the kiln. I then threw another urn the same size, using Laguna 65 clay - a greyish looking clay that turns white. I dried it, made the urn top, dried that, put it in the kiln. I usually preheat soak for 12 hours but it all seemed pretty dry, even the new piece that I put a heart onto, so I only soaked for 7 hours.

 

When I opened the kiln the next day, my B-Mix urn had exploded, taking three other urns with it. Ugh. It know it was that one, because there was nothing left and everything around it had damage on the side facing it.

 

I have decided that I am never using B-Mix again. My teacher loves it, she doesn't find it tempermental at all, but I think I get my pieces into the kiln more quickly, as I am making to sell. I'll stick to the 65, 60 and 80, thank you. 

 

Nancy

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I have been using B-Mix for a couple of years and have not run into the issues you have described. I throw ( relatively speaking) a lot of mugs, lidded jars, bottles, etc.  I am still a beginner and I would only venture to the guess the soak is not long enough or hot enough to sufficiently dry the pot before the high fire.  

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Morning,

I have long had a contentious relationship with B-Mix, Cone 5. When making mugs, more often than not the handles crack, pull away or fall off. When putting any kind of surface decoration onto the piece, it cracks, pulls away, or falls off. I've dried it naturally and slowly, with a dryer and a torch - they still fall off more often than not. I've used this "magic water" at class, slip, water, scratched the daylights out of it - they still often fall off. 

 

Last week, I picked up a still pretty wet urn about 7 or 8 inches tall I had thrown from the studio where I still take classes. I had thrown it two weeks earlier. It was B Mix, which is the only white at the studio. I let it sit out for a morning, dried it a bit, trimmed it, dried it a bit more with a dryer, and put it in the kiln. I then threw another urn the same size, using Laguna 65 clay - a greyish looking clay that turns white. I dried it, made the urn top, dried that, put it in the kiln. I usually preheat soak for 12 hours but it all seemed pretty dry, even the new piece that I put a heart onto, so I only soaked for 7 hours.

 

When I opened the kiln the next day, my B-Mix urn had exploded, taking three other urns with it. Ugh. It know it was that one, because there was nothing left and everything around it had damage on the side facing it.

 

I have decided that I am never using B-Mix again. My teacher loves it, she doesn't find it tempermental at all, but I think I get my pieces into the kiln more quickly, as I am making to sell. I'll stick to the 65, 60 and 80, thank you. 

 

Nancy

 

I am new to throwing and hand making and recently stopped using B-Mix.  I switched to another clay which I find has virtually no issues with cracking or separation of embellishments.  I thought it was just me being new and inept; good to hear someone else has similar issues.

 

 

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Nancy, I do like throwing with Bmix, but have had cracking issues in the past, but not problems with the handles falling off.  However, I have never thrown, trimmed and fired all in one day.  Maybe it's just because my climate is different, but it does seem like you are putting things in the kiln rather quickly.  I had my first explosion ever during a bisque a couple of months ago.  I knew I was taking a risk....the mug was still just a bit cool to the touch.  Lesson learned.   But like Mdobay said, sounds like it isn't the clay, the pot didn't have enough time to dry. 

 

Roberta

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Nancy

I liked it at first but then handles would crack where they were joined, round bowls would come out oval, but the most annoying was pieces of the foot ring or flat bottom would stick to the shelf--all during the glaze firing. Did not stay with that long!  I very much like Laguna #55. I have used it often over the years and is the only one I use now.  I like using a clay that I don't have to be fussing with...but I always make sure it is very dry....the extra time is so worth it.  Ginny

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I have never thrown with B mix but I know it's awful to handbuild with, my professor in college made me do a project with it to get me out of my comfort zone.   What a mess,  years later I tried making some tile with it and had almost every tile crack.  I had used the same molds and process for the tiles with a basic throwing clay didn't have one crack.  There are potters who love it, I can't figure out why.  Denice

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If you have a dry mix, (esp. 800 lbs), maybe someone else could use it or alter the product somehow to make it useful. Maybe it would make a good slip! Since you don't want it , maybe experiment with all sorts of colours/textures for slip.

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If you have a dry mix, (esp. 800 lbs), maybe someone else could use it or alter the product somehow to make it useful. Maybe it would make a good slip! Since you don't want it , maybe experiment with all sorts of colours/textures for slip.

It's got bentonite in it, I think. If it does, it'll gel as casting slip.

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Nancy, I do like throwing with Bmix, but have had cracking issues in the past, but not problems with the handles falling off.  However, I have never thrown, trimmed and fired all in one day.  Maybe it's just because my climate is different, but it does seem like you are putting things in the kiln rather quickly.  I had my first explosion ever during a bisque a couple of months ago.  I knew I was taking a risk....the mug was still just a bit cool to the touch.  Lesson learned.   But like Mdobay said, sounds like it isn't the clay, the pot didn't have enough time to dry. 

 

Roberta

Hi Roberta,

Usually I don't throw, dry and bisque in the same day. Last holiday when I was making a lot of mugs, I'd dry them for a few days under plastic, then another day out and Crack!!! The handle would separate from the mug! I was redoing almost every handle. Is there an ideal temp to dry BMix at maybe? My basement is cool, but my studio is warm. I've used both.

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Nancy, I do like throwing with Bmix, but have had cracking issues in the past, but not problems with the handles falling off.  However, I have never thrown, trimmed and fired all in one day.  Maybe it's just because my climate is different, but it does seem like you are putting things in the kiln rather quickly.  I had my first explosion ever during a bisque a couple of months ago.  I knew I was taking a risk....the mug was still just a bit cool to the touch.  Lesson learned.   But like Mdobay said, sounds like it isn't the clay, the pot didn't have enough time to dry. 

 

Roberta

Hi Roberta,

Usually I don't throw, dry and bisque in the same day. Last holiday when I was making a lot of mugs, I'd dry them for a few days under plastic, then another day out and Crack!!! The handle would separate from the mug! I was redoing almost every handle. Is there an ideal temp to dry BMix at maybe? My basement is cool, but my studio is warm. I've used both.

 

Nancy, It's pretty funny reading this thread about bmix.   Bmix seems to be a temperamental clay.  Your experience with the handles is exactly my experience with the cracking issue with bmix.  carefully dry it and before I can get it in the kiln, crack!  And I agree with your drying experiences also.  Doesn't seem to matter, cool, well ventilated, warm, covered.....it still cracks.  However Denice didn't have good luck with it for handbuilding, but that is the one place I have been able to use bmix.  It makes lovely trays, vases, tiles, etc.  What is it with good ol' bmix?!  When I use up this last 100 pounds, I probably won't buy more.  I have had much better luck with a mid fire porcelain.  

Roberta

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I cannot speak to mid fire clays but High fire B-mix dries uneven and is prone to cracking and handles can be problematic.

The only plus I can add is it throws well. I use about 200#s a year max for large forms and usually use porcelain if it's a handle form for the handle itself  as its about the same shrinkage.

It throws well for large vases and pitchers.

Mark

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In general I have had good luck with B-mix and love the buttery consistency of it. I am hoping reading all these posts wont jinx my good luck with it lol.. My instructor told  the class one day that Clay had a memory and I didn't quite believe him until I started using B-mix. Very noticeable when throwing bowls.

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Thank you for your advice and commiseration. I'm liking the 65, but #55 has been recommended to me. Anyone familiar with the differences? I find #65 a bit stiff to throw and harder for me to center amounts over 4 pounds or so.

Nancy

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Over the weekend I threw some straight walled forms using 4 pounds. The second pull is truly amazing, it just goes on and on and on. I have heavily altered the piece and added on other thrown and slab pieces. What I like about #55 is how you can push it or shove it and it responds really well.

 

This piece has a bowl for the top that was really altered to shape it. The top, body, and spout were thrown from fresh #55 and the bottom is slab from reclaimed #55. I always cover with plastic a piece that has additions for 2 days - always. I have no idea if the piece will pour correctly and not dribble all over the place - but that is a different discussion!

post-13363-0-10322200-1464187081_thumb.jpg

post-13363-0-72214400-1464187096_thumb.jpg

post-13363-0-10322200-1464187081_thumb.jpg

post-13363-0-72214400-1464187096_thumb.jpg

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Besides throwing so well, I love the very tiny specks that give it more life than just a plain white and my glazes look better on this clay than on any other that I have used ( and there were very many that I tried over the years). I make simple utilitarian pots and I am not good at drawing or painting so I like the few glazes I use to give them appeal.  Good luck with your search.  Ginny

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Over the weekend I threw some straight walled forms using 4 pounds. The second pull is truly amazing, it just goes on and on and on. I have heavily altered the piece and added on other thrown and slab pieces. What I like about #55 is how you can push it or shove it and it responds really well.

 

This piece has a bowl for the top that was really altered to shape it. The top, body, and spout were thrown from fresh #55 and the bottom is slab from reclaimed #55. I always cover with plastic a piece that has additions for 2 days - always. I have no idea if the piece will pour correctly and not dribble all over the place - but that is a different discussion!

Thank you and thank you Ginny also!! I'm going to pick up some #55 tomorrow.

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I've been using Cone 5 B-Mix since I started throwing 18 months ago. Aside from two handles that cracked slightly where attached, one mysterious and bizarrely convoluted crack in a bowl, and a few oval-ish bowls I haven't had trouble with it. When I throw, I check obsessively on the forms starting four hours later and the instant I can pick them up, I turn them upside down. If not, shortly after the rim is white and dry and the bottom is still soggy. 

It is the trickiest of the clay bodies that I use and I would say the most similar to porcelain. It does not tolerate "abuse" in the same way that my groggy sandy stoneware clay will. For example I will be throwing with the groggy Hawaiian Red and I can FEEL myself do something that in B-Mix would mean a ruined piece. The Hawaiian Red frowns at me and moves on. 

Ironically the B-Mix was the clay I first started to learn on so everything I've used since then (except porcelain) is ridiculously easy to work with by comparison. LOL

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nancy this is interesting reading all this about b mix.

 

i use B mix with grog ^5.

 

i have not learnt how to throw plates yet, but i have not had problems with bmix so far.

 

bmix is the common clay the schools, colleges and studios use here. our professor warned us before taking a piece to a local place to use their kiln to candle at home in the oven overnight at your oven's lowest setting so things dont explode.

 

everytime i think of bisque explosion i think its a drying issue.

 

i am in dry california. i throw cups in the morning and then cover them to dry. i come back next morning and pull handles. while the handles are drying i trim the cups. and then i attach the handles. about 45 mins between pulling the handles and attaching them. if i have more cups then i break it up into two sittings of pulling and trimming. and then air dried. put in the kiln either that evening or next day. however always the kiln candles overnight. 

 

i also have done sprigs and slip decoration. not had a problem either. i do have slip problems if the cup was bone dry or almost bone dry. if my cups felt too dry i'd cover it with paper towel and generously spray and keep aside for 15 -20 mins and then put sprigs or slip on (raised slip design using a hair dye bottle). 

 

i have never pulled a handle and kept them overnight. if i dont use them i toss them. they have never worked for me if i kept them overnight. 

 

i've never had an issue with cracking so far. 

 

i think perhaps because of its composition Bmix has a different way of drying. 

 

what is interesting is i have actually come across quite a few Bmix ^5 lovers. we had a clay conference recently with colleges all over the state represented there. i spoke to quite a few MFA students still using Bmix. in fact one of them was even able to take it to cone 10 without melting. he was experimenting with bmix ^5 and not ^10.

 

i have not heard any item explode in the kiln in the last few years in school. the teacher and lab tech tell me its coz they candle and then do a slow rise. 

 

i have not had an issue with handbuilding either. however i do use wax resist on fragile points to slow down drying. 

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nancy this is interesting reading all this about b mix.

 

i use B mix with grog ^5.

 

i have not learnt how to throw plates yet, but i have not had problems with bmix so far.

 

bmix is the common clay the schools, colleges and studios use here. our professor warned us before taking a piece to a local place to use their kiln to candle at home in the oven overnight at your oven's lowest setting so things dont explode.

 

everytime i think of bisque explosion i think its a drying issue.

 

i am in dry california. i throw cups in the morning and then cover them to dry. i come back next morning and pull handles. while the handles are drying i trim the cups. and then i attach the handles. about 45 mins between pulling the handles and attaching them. if i have more cups then i break it up into two sittings of pulling and trimming. and then air dried. put in the kiln either that evening or next day. however always the kiln candles overnight. 

 

i also have done sprigs and slip decoration. not had a problem either. i do have slip problems if the cup was bone dry or almost bone dry. if my cups felt too dry i'd cover it with paper towel and generously spray and keep aside for 15 -20 mins and then put sprigs or slip on (raised slip design using a hair dye bottle). 

 

i have never pulled a handle and kept them overnight. if i dont use them i toss them. they have never worked for me if i kept them overnight. 

 

i've never had an issue with cracking so far. 

 

i think perhaps because of its composition Bmix has a different way of drying. 

 

what is interesting is i have actually come across quite a few Bmix ^5 lovers. we had a clay conference recently with colleges all over the state represented there. i spoke to quite a few MFA students still using Bmix. in fact one of them was even able to take it to cone 10 without melting. he was experimenting with bmix ^5 and not ^10.

 

i have not heard any item explode in the kiln in the last few years in school. the teacher and lab tech tell me its coz they candle and then do a slow rise. 

 

i have not had an issue with handbuilding either. however i do use wax resist on fragile points to slow down drying. 

I did candle for pretty long - 7 hours. I usually do 12 hours. I haven't tried to turning them upside down, though. 

 

Giselle, my school is going to use B-Mix with grog. I think that is a LOT more forgiving. Also, the first clay I ever used was B-Mix, so when I am making a tall cylinder with 60 clay or the 65 and it isn't cranky and complaining to me, and wobbling around at all, I'm always surprised!! 

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john, i like your pitcher.  it looks as though you should do a video to add to the membership of the 3 pound, 12 inch cylinder club using that clay.  

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B-mix....I started a few years ago using cone 5 B-mix and found it to be pretty temperamental.

Though it's nice and smooth to throw like porcelain, it is pretty sensitive in how it drys.

I've moved to cone 10 and for example, in my outside studio this weekend we had record heat.

I threw a dozen lids and lost most of them (spiral cracks).

I paid very close attention to wedging, compressing, and drying in an enclosed shelf (shaded area, black plastic,even had a water bucket in there!).

9 of the 12 cracked...

Thin cylinders will warp, handles won't adhere. Only Bmix with sand or with grog are going to help this IMO...

 

Yes, these are thrown fairly thin, but still, the reaction to heat/drying is fussy.

These where made the day before, with similar weather albeit a bit cooler >>>

 

IMG_6139-XL.jpg

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I use cone 10 b mix a lot but its the one with grog in it. It raku fires well and I have had few cracking issues. But I dry stuff slowly and my forms are handbuilt and pinched so they get compressed quite a bit.

 

About a year ago we got a bad batch of b mix that seemed really "short" . Did not work well at all. We contacted Laguna and they said they were mixing it more moist. Lots at our studio use b mix and all were having problems. Many people switched to Dave's porcelain or other white stuff.  Somehow the problem got straightened out and I am back to b with grog. rakuku

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