Thursday, February 23, 2006
This is the first time I've made mugs from slabs-a technique I pinched from ex-Tel Hai-student Chen,and the only way I could think of getting this surface effect.The kiln,which we opened hot yesterday afternoon,was the best so far-lots of heat,bags of salt,pretty even.Sydney thinks we can do with less heat,I think we can do with less salt.We know nothing.
Which I showed you after its first test firing in the last salt kiln,when it looked fine and promising as a home-made alternative to ready-mix refractory.On a whim I stuck it back for another round with the salt,and now it doesn't look so happy,having taken on a green,glassy layer of salt-glaze.Mind you,Alon's sample pieces,made up from various recipes,and intended for casting his kiln at Tel Hai,all came out of this firing with vitrified surfaces too.The bought castable,from which the salt kiln is constructed,looks fine after about 10 firings [5 at its original site in my garden,5 at Sydney's].Possible conclusion:cast the kiln with an inner skin of the tougher commercial mix,back it up with a thickness of home-made.
Wednesday, February 22, 2006
We fired the salt kiln yesterday- 3 hours to load,9 to fire, our fourth firing,12kg salt,cone 10 well down in front.In a couple of hours I'm driving down to Yesod HaMaala to open the kiln with Sydney...as usual,neither of us has a clue what to expect [that's why we're doing it].Three [count them] pyrometers malfunctioned simultaneously at a critical point in the firing,I broke cone 7 loading the kiln,and a spare cone 9 perched on a [visible] shelf,our last means of temperature measurement,started to bend,then toppled over.The draw-rings were made of some unsympathetic white clay,and were unslipped,making them less than informative.Under such conditions,you just have to use your experience [between Sydney and myself,some 70 years], concentrate hard,and hope.
Monday, February 13, 2006
Pillar of Salt
Thursday, February 09, 2006
Year of the Blog
Yup,this blog is a year old today.Everyone's invited to the party.I've really enjoyed writing/filming it,and the contact it has given me with friends,colleagues and customers.If you're still inclined to drop me a line [and frustrated by the "no comments" rule]there's always email- email@example.com
Here is a mix of pix from 2 days of bikoret avodah/critique of students' work,end of first semester- as usual,emotionally and verbally exhausting and lots of fun.For more detailed shots [and more of them],ckeck out the students' very own blog,which,so far,they have shunned en masse.
We are currently enjoying miserable weather-cold,fog,wind,thunder,hail,rain,the works.Not enough to fill the Kinneret,but sufficient to provoke a sieries of drips in the studio roof.I'm off to fix the kitchen tap,then I might try to post the students' pictures.
Monday, February 06, 2006
What Does It All Mean?
I think I have proved conclusively that hand-cast shelves are not the way forward- a shame:it was a nice idea.This one,made from the same mixture as the kiln,warped extensively after one firing-the thrown version [my mix]even more.They did,however,sit rather nicely on experimental pegs sliced from thin kiln-shelf and slotted into angled holes drilled around the kiln-wall,removing the need for space-taking shelf props.My main problem seems to be heat distribution-too much heat is getting held at the bottom of the kiln,so the next set of shelves [I can just cut 2 from one of those perforated shelves I showed you recently] will be smaller to allow the heat to rise unimpeded.I don't know about you,but I am enjoying myself tremendously learning about kilns.And it only took me 30 years to get around to it.
2nd firing of test kiln
Yesterday morning I ordered another couple of gas cylinders and,to my surprise,they were delivered an hour later.I dug out a few glazed/unfired pieces,loaded up the kiln,and started firing early in the afternoon.Around 5 o'clock my sole semi-accurate pyrometer decided to call it a day,which added spice to the proceedings.There was much building of provisional chimneys and removal of same [didn't seem to make a difference] and at some stage I moved the burner from the port at the base to the spy-hole in the middle to try to heat up the top- resulting in these 2 cones keeling over almost instantly.Packed up around 9,at the bottom of the gas cylinder.This morning's opening revealed that the bottom reached 1260 with enough reduction to give a reasonable celadon;the middle shelf [where these cones 7&9 were] got to 1230/40,judging by the rather unfired appearance of the glazes,although the copper glaze showed signs of reduced red;the top shelf just about managed to melt some broken glass in a dish,but not the glaze.
Friday, February 03, 2006
Return of the Apprentice
Some nice little dishes Goldie made in Mallory's studio in Jerusalem- white earthenware,bought glazes- a different world,but just as capable of producing beauty.
Yesterday's trial firing finished around 11p.m.,having reached the region of 800 degrees and the bottom of the gas cylinder,in pouring rain.This morning,opening revealed no damage [always a desireable outcome];the kiln was a little hotter on the bottom which,as far as I can see,is a good starting point with an updraft kiln,whose nature is to be hot on top.It might also mean that the kiln could be a bit taller,maybe by adding a cast ring on top of the existing structure.All very intriguing- I hope I can squeeze in a high-temp. firing next week [two days critique at Tel Hai]- and then,maybe,sell the kiln...make another one...
Thursday, February 02, 2006
I suppose it was inevitable,with the combination of revived interest in kabbalah and all those yuppies spending weekends in Safed- next week a film is to be shot just up my alley-way,and already trucks of equipment are cautiously ferrying back and forth.Meanwhile,a fictitious girls' yeshiva is going up on a picturesque neighbourhood plot,as if there weren't enough girls' yeshivot in Safed...supposedly the film is to be called "Sodot",or "Secrets"- watch out for it at your local flea-pit.
I'm firing/curing the cast kiln today:we're up to the 500's,still on pretty low gas pressure,not going quite as slowly as the recommended 50 degrees/hour,but still taking our time.I plan on carrying on 'til the evening,aiming for somewhere between 800 [the end of the curing process] and 1000 degrees.The kiln is empty,apart from 2 cast circular and one thrown shelf and various insulating bricks masquerading as props.The 2 cast halves are standing on a floor of hard brick on a concrete-block base,wrapped in ceramic fibre blanket held in place by chicken-wire.The roof is just kiln-shelves with strategic gaps for controlling atmosphere[since this picture I have put a loose layer of insulating-brick on top],on the right is the single burner,on the left the lying pyrometer,in the middle Sydney's kindly donated wee gas-tank with its conveniently-controlable pressure-valve,which I am using [as opposed to the tap on the burner] to run the firing..The black pipe in the left background is not part of this story.