The Continuing Misadventures of Me and My Pugmill

Well, the pugmill drama continues...

Based on the suggestion of a fellow potter who commented on one of my previous blogs, I approached a plastics company to see if they could form a sleeve to fit inside the barrel of my pugmill. Unfortunately, this particular company was unable to help us, mostly because of the curve of the barrel at the extrusion end. But the fellow suggested we try an epoxy coating like ones used in elbows of pipes that carry grains and salt, and was even kind enough to give us a batch of the epoxy to use.

I was hopeful...



The first week went well. The epoxy seemed to be staying put. There weren't any more pesky chunkies buggering up my thrown work. And then, slowly but surely, I started finding the hints of chunkies. Small ones. But definitely chunkies. I brushed it off as dried bits of clay? maybe? hopefully?...

In the mean time my show in Ottawa came and went (thanks everyone, for a great show!) and when I got back, I had about 2 weeks to finish all the work I needed to get done for the remainder of my Christmas shows. So the first day back to work... pug some clay... start throwing...

CHUNKIES!

HUGE freaking chunkies. The size of m&m's.

And then...

EPOXY!

Yup. Slices of epoxy, coming off in the clay.
Shit.

So we took apart the pug mill, cleaned it out, and here's what we found:



In some spots, the epoxy had peeled right off and was mixed into the clay. In other spots, it had let go of the aluminum and was acting like an envelope. From what we can figure, the pressure from the vacuum pulled the epoxy away from the aluminum and clay got stuffed between the epoxy coating and the pugmill barrel.

We still can't really figure out where the chunkies were coming from. They did not appear to be stuck to the epoxy. And the clay that had slipped between the epoxy and the barrel couldn't get into the mixing clay because the epoxy holding it against the metal was still in tact. And the small chunk of epoxy that DID break off, was fresh and the clay didn't have time to react yet.

Soooooo.....

Luckily, the rest of the epoxy peeled off like cheap nail polish but we're back to square one again.

So, either I give Peter Pugger a call (I'm sure they'll be ecstatic to hear from me!) and find out if they are willing to get the sleeve made, or I get my incredibly talented husband to machine me a new barrel out of stainless steel and be done with the whole problem. The materials for this would cost us about $1000.00, and my hubby has access to the equipment to get the job done. All we would need is the time...

They're BaaAAAAck!

Well, the last few weeks have been nothing if not completely frustrating.

So here I am, custom orders on the go, wholesale orders on the go, desperately trying to stockpile work for upcoming Christmas shows, frantically trying to replace stock that has sold at summer shows. I'm busy. VERY busy. And I don't really have time for things to fall apart.

But alas. It had to be...

Remember that problem I was having a while back with my brand-spankin' new pug mill? Where my clay was corroding the inside of the mixing barrel and pesky little chunkies were making their way into my pieces?

Weeeeeeelllll....

The pugmill manufacturer recommended that I add epsom salts to my clay body. What this would do, I was assured, was change the pH of the clay which would in turn, prevent all those pesky little chunkies from forming in my pug mill. Okay. No problem. 44 grams, dissolved in hot water, added to 25 lbs wet clay. Mix, pug, throw.

No problem, right?

WRONG!!! What a complete disaster. Have a look for yourself:





Yup. Three kiln loads and counting. Ruined.

After much crying, cursing, Clayart-ing and phone calls, here is what I learned:

Too much epsom salt can cause blebbing. As a piece dries, the salts migrate to the area of the pot that is drying the fastest (the rim in most cases). During firing, the salts will turn to gas and generally burn off. However, if there is too much salt, and the clay begins to mature before all of the gases have escaped, you will end up with what I have in the photos. Lots and lots of little blisters, all over the rims of a couple of thousand dollars worth of pots. As my luck would have it, my clay manufacturer ALREADY adds epsom salts to their clay. So by adding more, I overloaded the clay.

So there you have it folks. My advice: talk to your clay manufacturer before adding ANYTHING to your clay body. No matter WHO told you to add it.

Aaaaaaand in addition to that...

Those f'ing chunkies are back, busily corroding away at my pug mill.

Yup.

oh! And that would be the NEW version of the pug mill. The one with the corrosion-resistant coating.

Yup. My luck.

The Perfect Pour

One of my favorite teachers from art school always said "if you're going to make functional pottery, use it!" So when I made one of my first functional teapots, I brought it straight into the house from the kiln and made a pot of tea. (Steeped for 5 full minutes for the perfect cup of Bourbon Vanilla). I picked up the teapot in great anticipation of my perfect cup of tea, and was horrified as the tea gurgled and blurbled out, down the side of the pot and everywhere but the mug, strategically placed beneath the spout.

I was so disappointed.

BUT...back to the drawing board.

Functional teapots are one of the biggest challenges for potters. They employ a great variety of throwing techniques, complete with lids, knobs and handles. They have to pour properly, hold enough tea, and not be too heavy. All of this adds up to a steep challenge. (No pun intended.)

So what exactly is it that allows a teapot to pour?

Well, first there's the obvious: the spout. Spouts need to be wide at the base and taper to a narrow opening at the end. This helps to push the tea out and far enough away from the pot to keep it from clinging to its side. But we're not done there. Spouts need to have a relatively sharp end to help cut off the flow of the tea as the teapot is righted. Unfortunately with pottery, too sharp will often lead to a chipped spout. If you can find a teapot that lets no more than ONE drip back down the outside of the pot, you've done good!

Spouts aren't the only important aspect to a good teapot though. The handle also requires some special considerations. Handles must be placed in such a way that the pot is balanced as the user is pouring the tea. This relieves strain from the wrist, and lets the pot do all the work. For best results, look for a 90 degree angle between handle and spout. The handles also need to be beefy enough to hold a full pot of tea. No one wants to see a full teapot release from its handle and go crashing to the table.

Some other small considerations include a wee little hole in the lid. Air needs to be able to enter the teapot as the tea is exiting to allow for a continuous, uninterrupted pour. And if the teapot is meant to be used with teabags, have a look inside to make sure there are holes creating a strainer of sorts, where the spout attaches to the pot. These will catch a teabag and prevent it from plugging the spout.




It's been a few years now since that first disastrous teapot of mine, which I still have. And I've abandoned the Bourbon Vanilla for a quieter Tongyu Mountain Green tea from one of my favorite tea stores, Distinctly Tea in Waterloo. But man, I do love a good cup o' tea.

Perhaps I should have listened to my gut...

The past few weeks have been somewhat frustrating to say the least. I have recently changed clay bodies. Having had repeated problems with the one I had been using, I decided to try a new one.

Great. No problem. Until I opened up my pug mill to clean it out. Ughhhh!

So porcelain will react with certain alloys in metals. I knew this (although I confess I didn't exactly know what 'react' meant) and researched pug mills accordingly. When it came time to buy one, due to some injuries, the Peter Pugger VPM-9 was recommended to me. After reading testimonials, I decided 'sure, why not!' and that's the one I brought home. After about a month of loving this particular little machine, I started to find little hard chunks in my clay as I was throwing. These pesky, hard bits made throwing and trimming incredibly frustrating, and after firing, led to lots and lots of seconds. These bits bulged out and fired a different color. Grrrr! I figured it was just more 'stuff' in my clay, that I had been having issues with for some time, but when it was time to clean out Piggy (which the pug mill was affectionately nicknamed) I was shocked to find those pesky hard bits stuck to the inside of the pug mill. And they appeared to be stuck ONLY where there was some over-spray paint on the inside of the mixing barrel.

You'll notice in the image on the top, all the little bits stuck to the inside of the pug mill. When they finally break off, they take the paint with them. Turning your attention to the image on the bottom, you'll see that there is absolutely NO little bits stuck to the parts of the pug mill that have no paint.
I called Peter Pugger for some advice and they suggested Airplane Paint Remover so that's what we did. Sprayed the inside, waited, scrubbed out all the paint we could. And now we wait. I hope, hope, hope (finger's crossed) that these little chunkies don't return. I've got about three more weeks to find out. (Sigh) The most maddening part is, I WANTED the stainless steel pug mill from Venco, (which was considerably more expensive) but got the Peter Pugger on recommendations from my supplier and other users. Perhaps I should have listened to my gut...

More felt, more glaze tests, more frustrations...

Okay. So this has been a rather long and somewhat frustrating week. I managed to get a glaze firing in, along with some of those tests that I am working on. You'll recall from my last post, the problems I was having with my glaze running too much


I mixed up a couple more tests. Both tests are an altered version of the original matte glaze recipe, G1214Z from Digitalfire. I changed the glaze with my Insight Glaze Calculation Program to allow for a 5% increase in Silica. I thought I'd start with this alteration in my tests because it would help to stiffen the glaze and keep if from running, by slightly bumping up its firing temperature. I'm not very happy with the results. The tile on the left has no opacifier, the tile on the right does. You'll notice that I managed to correct the problem of the glaze running too much, but I think I prefer the matter surface of the original glaze recipe. So back to the testing... I think the next round, I'll work on the levels of EPK. If I increase the EPK and the silica at the same time, I may be able to both fix the running, and push the surface more matte. If I simply remove the extra silica and increase the alumina (EPK), then I'll make the glaze more matte than the original, which I don't think is what I want to do. I have to be careful adding too much more EPK, because that can cause the glaze to crawl. Here's an article about this glaze recipe, for further reading.

Back to my felting, I've started decorating some of the tiles I was working on last week:

The small piece on the right is a test piece I tried. The red stripe was wet-felted in place. This creates a very soft and fuzzy line. For the tile on the left, the red lines were added by needle felting. The two colours of wool do not blend the same and the red is much crisper. Personally, I'm leaning towards the look on the right. So I guess I'm testing more of this as well. (I see lots of testing in my future...)

I found some craftspeople online who are willing to answer my questions about felting so now I've got some brains to pick. The RagingWool has offered to help me (I know! Great name!) and so has LaLaFelt who has some amazing roving in stock!

So I'm off for another week of testing: glazes and felting. Enjoy!