Wedging: it’s not about air bubbles!

Wedging. Who writes about wedging?

Isn’t it to get the air bubbles out? (NO!) And wedging is one of those zen practices that supposedly take 3 years to learn to do right?

Or, is it, in my experience, to get an internal coil going in your clay so that when you are throwing and you start to center on the wheel, your clay doesn’t fight you and centers up easily?

Why we wedge is something many potters know or have known throughout time but is still something I think should be discussed again; especially for art educators out there.

For years and years  and still! I have wedged Japanese style; spiral wedging (pointy end under my left hand, right hand on the fat- butt-end) with the spiral  at the fat end of my clay- running counterclockwise. That is, if you looked down on the fat end and imagined the spiral turning, it would spin into the center going counterclockwise.

Yes, I painted on the clay to try to show the spiral direction- which is counter clockwise when the fat end is pointing up- but when you put it on the wheel- it’s going clockwise!

Then I  plopped that fat end of the clay down on my wheel-head and proceeded to throw American style with the wheel running counterclockwise (and the internal spiral going against that- clockwise) and I would very frequently have to battle my clay a bit to get it centered.

So often,– and especially after I got really consistent and more skilled at throwing– I noticed my clay would just refuse to totally center. It would get this little blip- a wobble, a part that seemed like it simply refused to settle down and let me get the clay all-the-way centered and I knew I was doing everything else right. Even if I coned it up and then brought it down just right, there would be that little blip again that I would end up trying to work around. Or, after I got the walls pulled, I would wonder why my pot would suddenly get some sort of odd wobble in it for no apparent reason.

Why did my un-wedged smaller lumps of clay behave so much better? For a while I gave up wedging anything that came straight out of the bag but for large pieces, it was pretty tiring getting it centered.

Finally, overhearing another teacher at Lill Street mention offhandedly something about the spiral helping to center the clay and, at some other point, after beating my clay into submission yet again and feeling like I was not going to always be this strong, a careful examination of the direction of my coil came the realization that the way I wedge was Japanese (the wheels in Japan go clockwise) but my throwing is western ((American wheels spin counter clockwise)

And it takes a fair amount of visualizing to figure out which way the internal coil in the clay is going once you’ve popped it onto the wheel. The fact of the matter is, it was pointless to wedge my de-aired, pugged clay if I was going to put the internal coil going against the spin of my wheel!

note!!!!

I don’t know how many countless people, students, educators, etc, have asked me, “don’t we need to wedge the clay to get the air bubbles out?” The answer is an emphatic NO!

Air bubbles in and of themselves are not a problem! It’s only the moisture* they hold that cause explosions. If something is properly dried, you will rarely have explosions.

So please don’t waste your time or your students’ creative-time wedging clay that has been already de-aired in a pugger- i.e. any commercially made clay- clay you would buy in a box.


This clay has been de-aired in a  pugmill. There are usually no air bubbles in it!

In fact, improper wedging will more often add bubbles and you willl just dry out your clay in the process.

Simply make sure the pieces get enough drying time and have no plaster mixed in with the clay- that IS a sure recipe for explosions.

So why DO we wedge?

When it is for throwing**, it is for getting an internal coil in the clay so it is easier to center the clay. I do not wedge anything under 2-3 lbs if it comes straight out of the bag,I save that effort of wedging in an internal coil for larger pieces of clay when I would be wrestling to get a piece centered.

Here is how I currently work: any clay straight out of the bag under 2.5 lbs does not get wedged.

It is airless and too small to matter. 2.5 -3 lbs get wedged the new way trying to train my poor hands to reverse their roles and anything over 3.5 lbs is wedged the old way and then flipped over.

Did I find it easier once I flipped my wedged clay upside-down onto the narrow point but with the internal coil now “tightening” when my wheel head went around?……Immensely.

All those old problems disappeared and it was much easier to center. Just recently I forgot to flip a wedged piece, began to center it, felt the blip and realized what I had done and so I actually cut it off the wheel and turned it over and then it was just fine. What a great illustration of what I had been learning.

And yes, I mentally slapped my forehead for not figuring this all out years earlier!

Oh well, better late than never and since I did not figure it out for so long, I thought I would share what, in retrospect, seems like an obvious fact with all you out there who may have also missed it.

*Why is moisture a problem? Once the clay hits the temperature of water boiling, any water will, in fact, boil and turn into rapidly expanding gas which has no space to expand. The result? An explosion as the gas pushes the clay out of its way.

**There are just a few uses for wedging when you hand-build. Chiefly it would be to even out clay that had been stored a long time- say one side is a bit drier than the other. When I hand-build I use it to make sure my slabs shrink back evenly in all directions- but just take a look at my blog entry on throwing a slab vs. slab rollers for an explanation of that.

***

And while I am on the topic of de-aired clay, I had a batch of reclaim that I took to a friend’s house and used their Soldner mixer to get it back in shape. I ended up with 300lbs of porcelain filled with micro-bubbles. I slam-wedged it quite a bit but I could never get out all the millions of tiny bubbles so I tried throwing with it. It was very interesting! I could throw a lot taller with it, The clay was stiffer and a bit shorter.  “Shorter” in clay terms means that it is less plastic, it won’t stretch as much. Clay is always a balance between wonderful elasticity and not having floppy collapsing clay. In porcelain, I feel that line is even more delicate.

It was great to make a lot of tall and large things out of grolleg porcelain and I simply avoided pulling handles from it or bringing down wide rims or even making a pitcher spout with that particular clay. I used my regular clay to make handles and they fit the mugs I threw just fine. My other concern was a lumpy surface and I did 2 things; I ignored it and the bubbles seemed to flatten out in the firings and I also took a serrated rib and ran it over the whole surface while I was throwing and then smoothed it again. Neither method was perfect but I used up (and sold the end products) of all 300 lbs.

When I discussed this batch of clay with my friends who had lent the mixer, he had also mixed a batch of porcelain with similar results, a stiffer clay. He quoted a old potter who said pugging ruined clay.

This is one of those posts where I would very much welcome comments from potters who will know more about this than I do.

So what are your thoughts and opinions on wedging?

Weather drama at the Kohler Festival of the Arts

For some odd reason I’d hoped to get through this latest art fair without any dramatic incidents but of course that would not make for a good story!

We rented a trailer again- it’s really easy to load and then we have our own car the whole time.  The drive to Sheboygan was lovely.

This person travels heavy!

When we got there, there was ample space to just pull up and it was shady too.  We unloaded and then ate a picnic lunch right on our spot.  As we prepared to set up they decided they had to do some last minute mowing!

Set up is getting smoother as we become more practised and find short cuts and routines.

We had a really nice spot.  

As soon as we were done, we went right over to the Kohler Arts Center. The exhibits were excellent. Interesting, thought provoking and sophisticated.

Then there were the bathrooms.  Luckily our little group (my family)  had genders of both kinds and so got to give each other the “all clear” sign so we could view ALL the bathrooms (there were 4) Here is the main Men’s note that the mirrors are reflecting the other wall – all of it was AMAZING.

my favorite was this Women’s Bathroom.

And the other Men’s was also great.

it was all about water. Although that paisley pattern has a germy look.

Next we went out to eat at Il Ritorno- OMG!  The best pizza I’ve had in years!  Possibly ever! Also a great salad.  Sated, we went off to our hotel which has an attached water park and we all went on slides and inner tubes etc. until we were exhausted and saturated with chlorine.

The next morning dawned beautiful and sunny but I had a fairly slow day. At some point I left the husband in charge of my booth and walked around.  I was really impressed with all the great pottery. I now own some pieces by Michael Kahn of Greenbush, Mi. and also Ryan Myers (who won an award at this fair) of Mudhead Studio.

As soon as we packed up for the night (all the pots in boxes on the ground) we went over to the(  free)  Artists Buffet and Awards Dinner. This is the 40th anniversary of the Festival.  Chinese food, great salad and beer or wine; very nice.

Another winner was Sarah Chapman a fellow Lill denizen- a jeweller.

Back to the hotel where we had a walk on the beach and the kids did the water park again.  So far incident free, right? Everything going smoothly… BORING but smoothly.

The next morning we got all set up- we had the awnings down overnight because of possible wind- and right after we got all set up it rained on us pretty hard.

Unlike 57th Street, that didn’t scare the customers away for the day- they came out with the sun and I had a slow but steady day.

THEN with 45 mins left to the fair, while a volunteer was shopping in our booth, this HUGE TORNADO SIREN goes off. We were about a half a block from it

it was so loud it obliterated all thought and all my decision making functions in my brain shut down.  Should I take my kids to the nearest basement? Should I try to pack up my pots? Was it a REAL TORNADO?? What if it was just a strong wind? Kids would be okay but the pots could be detroyed…. but what if it was a REAL TORNADO? Then I didn’t care about the pots at all….. finally the sound stopped and my brain unfroze. The jeweller across the way who had already lost a tent that weekend (his wife was in Iowa at a different show and wind destroyed their better  tent) was packing up extremely rapidly – to put it mildly.

It looked to me as though the artists all decided, “okay, the customers are gone, it’s been a fair with lackluster profits* let’s just call it a day”

*let me just reiterate here- the fair itself was really really nice- well run, great art, lovely setting, good treatment, good music. These are just tough economic times.

So we all began to pack up.The sun actually came out again and everyone was pretty relaxed.

Amazingly, some customers did return only to find the things they’d been eying for several hours packed away.

Load out was easy, and we were headed home by 6.

Oh, and by the way, there WAS a tornado- north of us!