Our on-going pug mill saga

Over the past couple of weeks, we have been making pots, working towards the June Long Weekend ‘Pop-Up’ Open Studio Weekend.

I have finished building work for a while. I need to be making pots, no more work on the house until later in the year. I still need to fireproof the facia and eves of the roof against ember attack. The roof is now completely watertight. That’s the first step complete. Andy came back to help me fit the last sheet of roofing iron and then screw down the ridge capping, while I followed behind peening the ridge capping into the corrugations of the roofing iron. A very solid, proper, solid job of roofing. I’m glad that roof work is now over for some time. 

In the pottery we have been throwing and turning domestic items like cups, bowl and plates to fill out the shelves for our Open Studio Sale. 

I made 100 cups.

On the on-going pug mill front. I stripped down the big blue pug mill and took the motor off and sent it away to be re-wound and repaired – if that is at all possible? I should know in a weeks time. In the mean time, I took the worn-out vacuum pump off the purple pug and swapped it for the good one that was on the blue pug. So now I have a good working 3” purple pug that we are using for our white stoneware clay and the buggered vacuum pump is now on the blue pug mill that has no motor. A matching pair of non-goers. Well for the time being at least. I will get back onto that problem after our Open Studio Sale. 

The blue pug is hoisted up onto a tressle to keep all the new, clean gear box oil down in the gear box while I take off the motor. There is no easy, clean way to drain the oil without some mess, so I’m leaving it here for the time being. Hopefully the motor can be rebuilt and back on the machine within a week or so?

I rang my friend John Edye recently and enquired about the 4” Venco Pug mill that he had for sale a while ago. I bought a lot of his equipment last year when he retired. I didn’t make an offer on the pug mill, as I thought that I was going to get a couple of pug mills from other friends. As these have proved to be a little bit problematic. A rang John and asked if the big pug was still for sale and amazingly it was. I’m so lucky! I bought it over the phone and made the trip up to John’s place to pick it up. Luckily, it isn’t as far away as Melbourne and I could do the return trip all in one day. John assured me that it worked, but that it had a lot of corrosion inside the barrel. I’ve dealt with that before over the years by fill ing the worst holes with a home made epoxy based filler, or ‘wick-in’ thread sealant, that seeps into crevices and sets in the absence of air.

When I got the pug mill home, I was able to lift it off the truck and straight onto a wheeled, steel pug trolley that I had welded up in advance. I even had a vacuum pump cradle welded on underneath for the pump. These machines are way too heavy for me to lift, so having them on a mobile trolley is the way to think about them.

It’s interesting that this machine is the first model of Venco 4” vacuum pug mill and presumably dates from the late 1970’s. It has an inline plunger handle and all the castings are different from the later models.

I had a bit of trouble getting all the bolts loose to strip the pug down to clean it out. A few bolts needed the impact-driver to get loose and one snapped off, requiring the hole to be drilled out and the thread re-tapped. Slow and a little bit tedious, but all do-able.

The pitting is deep, but hasn’t gone through the wall and with a little bit of maintenance, will see me out I’m sure. I cleaned everything back to the metal. There was a lot of flakey white aluminium oxide to clean off.

Some etch primer, followed by a couple of coats of paint and it is all back together now and ready for work. I’m not too sure how John will take the new colour scheme I’ve chosen to cheer up the clay making area of the workshop? Pink, purple and mauve, with a little bit of black detailing. I like it!

When all of this clay making machinery trouble is all sorted out, it will make our life so much easier. I am committed to making almost everything myself. To be as self-reliant as possible, in food, in water, in electricity, in wood fuel, and this extends to clay and glaze making in the pottery. The principal difficulty that I am dealing with here is that I’m trying to replace in a couple of years, what it took me to build up over the past 40 years of life experience. I don’t remember it being so difficult in the past, but I guess that I was only dealing with one or two problems per year over that extended time. Now I’m trying to do everything at once. It is a bit easier this time around as I have more life experience and more skills, but I’m so much older now and I don’t have the same energy that I used to. I certainly find it harder to go back down to the workshop at night, after dinner and continue working. Although I still do sometimes!

June Long Weekend Open Studio, 11th to 13th June

Janine and I will be opening our new pottery and gallery space on the long weekend in June.

We will be taking part in the Southern Highlands ‘Pop-Up’ Open Studios long weekend.

We have been working hard, both on and in the building. 

We will have new work ready in time for the Long Weekend 11th, 12th, 13th of June.

If you can find the time to come and visit us, we’d love to see you here.

We’ll have cake and coffee to share and a chance to give you a guided tour of the new workshop. It’s almost finished and everything is coming together.

If you want to make a day of it, or even a full weekend away. There are over a dozen other artists studios, all open here in the Southern Highlands over the weekend.

If you have your own social network, please feel free to send this poster out to your friends as well.

We look forward to seeing you at some time over the long weekend.

Bummer

I thought that everything was going so well.

Well, I thought it was. With 2 pug mills apparently fixed. I decided to make up a few batches of clay in the repaired ‘phoenix’ dough mixer. We had run out of the last quarter tonne batch of clay. All we had in the clay box were several bags of recycled turnings that really needed wedging thoroughly, or pugging. We opted to mix all the re-cycled turnings in with the new batches of clay and pug it all together. All well and good. It should have been so easy.

The dough mixer worked perfectly and I soon had a batch of plastic clay on the clay trolley and out to the rebuilt pug mill. Janine started pugging the clay while I mixed a second batch. Each batch is comprised of 100kgs of dry powdered clay, felspar and silica. These powders are all mixed together dry,  then I add 24.5 kgs of water to the batch and the mixer stirs it all together into a stiff plastic, sticky mass. It then has to be hauled out of the mixing bowl,  bit by bit and stacked onto the clay trolley to be wheeled out to the pug mill.

I could hear the big pug motor ‘whirring’, the gear box grinding, and the vacuum pump making its ‘phut’, ‘phut’, ‘phut’, noise. as I worked in the clay mixer room. Then nothing. When I came out to get the clay trolley to reload it with the 2nd batch. Janine was standing there looking a bit puzzled. The pug mill had stopped. The motor was working when I rebuilt it, but that was without any load on the motor, just ‘free-wheeling’ . As soon as the clay went in, the load on the motor increased and it just stopped. The over load switch clicked in and it wouldn’t restart.

Bummer! We now had 2 loads of clay needing pugging and a machine full of clay, but no action. I couldn’t do anything about it right there and then. The machine will need to be stripped down again at some stage. But right now I need to pug this clay. The only option was to wheel ‘Pugsly’ out. I was hoping to keep it clean and ready to pug the first batch of porcelain clay. That’s now a pipe dream. We start pugging the white stoneware through Pugsly. It starts well enough, but then I realise that the vacuum pump isn’t working. It’s making the right noises, but the clay is coming through with air bubbles in it. I can lift the lid off the vacuum chamber white it is working. This lid should be severely locked down tight by the vacuum pressure. Again, I can’t do anything about it immediately, I’ll have to figure it out later. I need to get the clay made, bagged and into the clay box, before it dries out.

I just spent a month of all my spare time re-building these two machines. One doesn’t work at all and the other doesn’t work a very well. I’m a complete failure as a mechanic. This is a real lesson in humility. When all the clay is finally pugged. Tonights dinner will be humble pie for me.  One small up-lifting part of this whole disappointing exercise is that the paint work was a success. It’s bright, colourful and cheering. That’s a small reward.

We spend two days processing all 400 kgs of clay and putting through the pug mill twice. Each batch is pugged and laid out on the clay table in rows and layers of sausages. Because there is the possibility that I could have made an error while weighing out the dry ingredients, or that there might be slight variations in the materials as delivered in the various bags. We pug all 4 batches of clay, then chop the ends off every sausage and re-pug the clay to make sure that every sausage that come s out of the 2nd process has all the same consistency. This is then bagged and stored in the clay box. It’s a bit of teamwork to get it all done efficiently and as quickly as possible, with as little mess as possible. However, inevitably, There will be some clay that gets dropped on the floor.

Once all 400 kgs of the clay is pugged, bagged and in the clay box, a very slow process, as the 3” pug is so much slower than the bigger 4” one. We have to clean up the floor to control the dust. A very small successful part of this protracted failure is that I built all the clay tables and trolleys on wheels, plus I mounted both pug mills on castors. We mop the floor all around the pug mills. Then wheel everything out of the way, and clean the floor under where the pugs were. It’s all quick and easy, and every part of the process of cleaning up is a success. It’s soon time to roll everything back into place. Ready to start pulling both machines to bits and finding out the problems involved, then sorting it all out.

Jane’s big pug has a motor problem. It wants to start, but can’t get going. It must be the starter windings or the starter capacitor. I pull the motor off and take it into town to find someone who knows about such things, to get the parts that I need to get it going again – hopefully. I’m told that it is most likely the starter solenoid. There isn’t one to be had in Mittagong at either of the electrical workshops, so I order one. It should be in next week. Watch this space.

Now for Pugsly’s vacuum pump. I think that it is something to do with the valve, hose and filter, vacuum air line. I disconnect the plastic hose, turn on the vacuum pump and put my finger over the end of the hose and it has hardly any suction at all, but there was some, just a tiny bit. I pulled it all to bits and found a few things out. The first was that the filter had been installed back to front at some stage in the past. Someone has had it to bits at some stage in the past and put it back together back to front. I hadn’t thought to check that when I started work on it. I’m totally hopeless as a fitter and mechanic.

When I got it off. I also discovered that it was chocker block full of white clay – on the pump side, not the pug side of the line. This is theoretically impossible, so that was a bit distressing. As I continued to dis-assemble it all, I also found that the sump of the pump had white clay mixed in with the oil! That would have ground out the bearings! I drain the oil out and replaced it with fresh oil. Ran it for a short time to rinse out all the old oil from the crevices, then drained it again and refilled it with new oil again. After reassembly, I test it and it has quite good suction. So not such a bad outcome. 

I decide to have a look at the vacuum pump on the big pugmill. I discover that it has been over filled to the brim with oil. I drain 2/3s of it out until it is back down to the indicated upper level in the sight gauge. Everything else seems to be in order. However, because I’m such a hopeless mechanic, there could still be more issues to deal with the next time that we get to test these machines out.  

It would have been so much easier to buy new machines from the start and I wanted to. I even had the money for them set aside to pay for them. But ‘Venco’, the pug mill manufacture here in Australia closed down a few years ago, when Geoff Hill, the proprietor died. The company has re-started under the new ownership of his grand son, but only in a very small and intermittent way. They have no plans to produce the 4” pug mills for some time yet. So far they have only made 2” pug mills, with the first batch of 3” pugs coming through now.

So I am stuck with my ineptitude to muddle things through.  I will get it all done, but it is frustrating and very, very slow.

Running Repairs and Fixing Old Stuff

This last few weeks has seen us making pots, but also getting into some serious repairs and maintenance.

I was outside digging over the ‘cottage garden’ preparing the soil for sowing seeds of a spring/summer flower garden show of colour. I know that now is the time to plant out seeds for spring in this flower garden, as in the veggie garden, where we go almost everyday to harvest food for dinner, do a little bit of weeding and plant out successive sowings of vegetable seeds. I see that the red ‘Flanders’ poppies are germinating in the freshly dug soil where I have recently planted garlic cloves. Poppies decide when the time is right to germinate, but they will only germinate in freshly turned soil. So now is the time to dig over the cottage garden site.

I whipper snipped all the old foliage into mulch, raked it all up and onto the compost, or used it as mulch in other places in the yard. 

I took what I thought was the easy alternative of using the cultivator. Not so! I only got 1/4 of the way round and the fuel line blocked up. This machine is a little beauty. I bought it 45 years ago, second hand for $50. It has just gone and gone and gone on working. I only use it a few times a year, but it is so much quicker and easier than hand digging with a garden fork if there is a lot to do. I tweaked the old rubber fuel line and it just snapped clean off in my hand, trailing petrol straight down onto the soil until the small petrol tank was emptied. I walked to the shed and got a pair of pliers to remove the stub end of the fuel line. It was very brittle as its quite old. I have replaced the fuel line a couple of times over the 45 years that I have owned it. The remaining length of line is too short to re-join for a temporary fix, so its another long walk to get some more fresh fuel line from the maintenance shed. With repairs completed, another walk to the fuel shed to get some more petrol and I’m back in business, just a half hour later.

I love this old cultivator. It’s just like me. Out of date and long past its use-by date, but it just seems to be able to keep on going, and going. So solid, reliable and old fashioned. Not very complicated. A good worker. I’m happy to spend time maintaining it to keep it working. It’s a pleasure to be able to own and use such a lovely old Australian made, solid machine that works so simply and so well.

I completed what I set out to do with no more interruptions. Luckily, I had all the parts that I needed on hand, so the job was started and finished on the same day. It’s not always so.

We borrowed Sandy Lockwood’s small pug mill over Xmas and January, as she wasn’t using it over the break and was happy to lend it to us. My wrists weren’t up to wedging another quarter tonne of clay again, so It worked out very well for us both, because after we had finished pugging the new batch of clay and also working through all our stored up re-cycled and bagged turnings and throwing slip. I pulled the pug mill to bits and cleaned it right out. I even saw that the chassis was getting a bit rusted in places, so I cleaned it back, rust converted it and painted it black again. Good as new when we returned it. This pug mill has never been in such good condition since it was built.

That batch of clay is now all used up, so we need to be getting on with getting another pug mill working. 

In the old pottery, before the fire, we had two 4” or 100mm dia. Venco vacuum pug mills. One for white clay and one for dark clay. I also had a 3” or a 75mm dia. stainless steel pug mill just for porcelain clay and finally we had a very small 2” or 50mm dia. stainless steel pug for small batches of test bodies and recycling of turnings. That was such a good position to be in. Luxury really. It took me over 40 years to get to that position.

At the beginning of the year, we were given a pug mill from our friend Toni Warburton. It hadn’t been used for a long time. Perhaps 20 or more years? It had been stored in her back shed for time out of mind and was full of dried out clay. That’s not such a problem. What was a problem, was that it had never been taken apart. so all the bolts holding the 2 halves of the pug mill barrel together were rusted and swollen up in their sockets. They couldn’t be removed or even rotated. I could have snapped off the heads trying to get them loose, but then the shattered off ends would have made them very difficult to drill out accurately. So I decided to just drill them all out straight from scratch. A very long and difficult job.

Drilling out all 8 of the bolts took some time. They were all 90mm long, so I started off with a 3mm pilot hole, then increasing from 5 to 7, and then 9mm drill bits, until the bolt was completely hollowed out and could be removed.

I was wondering if I would get away with it, but I didn’t snap off any drill bits, especially the first 3mm drill bit. That would have certainly put an end to it.

Once I got the barrel apart, I could clean out the dry clay and start to clean it up. The pug mill had previously been used to prepare dark iron bearing terracotta clay. However, I want to use it for white stoneware, so It had to be cleaned out very well. scrupulously well. I made a thorough job of it, starting out with a paint scraper and generally progressing from hand held wire brush, through to a circular wire brush in an electric drill and finishing off with an angle grinder for the most stubborn bits. 

I set about removing every trace of terracotta from both the barrel castings and the stainless steel blades and shaft. They cleaned up pretty well. I ground the barrel back to bare metal and gave it a good coat of etch primer to seal it. This wont last in the places of heaviest wear, like in front of the shredding screens and in the reduction cone of the barrel, but elsewhere it will help minimise the ‘salt’ corrosion caused by the alkalis in the clay reacting with the bare aluminium metal under very wet and humid conditions. The barrel is cast out of marine aluminium, but eventually it still corrodes. In the last pottery, I replaced the oldest barrel that I had on my oldest ’70’s ‘Venco’ pug mill in 1984. It was starting to get corrosion patches breaking through the barrel after 35 years! I kept sealing them with ‘LockTite’ ‘wick-in’ each time I took it to bits and serviced it. The Locktite seeps into the crevices and then ‘gels’ to seal off the void.  Very cleaver. If this barrel lasts that long, it wont be my problem! Someone else will have to deal with it.

Toni had christened this pub mill ‘Pugsly’, so that is its name now and forever. However, I gave Pugsly a bit of a spruce-up and a new coat of paint. 

Bright and cheerful and ready for work. I mounted the vac pump underneath to keep them both close coupled and easy to move around on the one solid castor unit.

This will be our old, but new, porcelain pug mill.

Last year our good friend Jane Sawyer offered us her old Venco pug. She had bought it 2nd hand in the 90’s. She offered it to us as she wasn’t using it anymore. She has another one at ’SlowClay’. This pugmill had stopped working at some stage and was surplus to her needs. We had tried to get it trucked up to Sydney, but no taxi truck company wanted to take on the job of delivering it to the trucking depot for transfer to Sydney. The only quotes I could get were approaching upwards of $1,000. Way too much! So at the start of April. Janine and I made a lightning trip down to Melbourne to collect it. We drove down in the ute, as it has a crane on the back, built for lifting such heavy gear as this. We had 3 days with Jane and took a day of rest to walk into and around Melbourne. The 10 hour drive each way was a bit boring. We changed drivers every 2 hours. It has been a very long time since I drove to Melbourne. The road is all dual carriage way now and a very comfortable drive. The truck is not particularly fuel efficient, so the 20 hour drive cost us $300 in petrol. 1/3 the cost of getting it trucked. But at least we now have it! The best part was that we got to spend a few days with Jane. And, It arrived home safely without being damaged in transit!

This image by Jane Sawyer.

Once home I started to get the pug mill to bits to clean it out. It had also been used for terracotta, so a lot of cleaning was needed. The motor still made a noise when switched on, but instantly went into overload, shut down and stopped humming. It appeared that either the gear box was broken, jammed or a bearing was seized. The only way to find out was to strip it all down to basics. This was easier said than done.

The bottom half of the barrel had seized bolts. I snapped off one of them trying to get it loose, so decided to drill out the other. Once the barrel was off, I tried to remove the collar connecting the gearbox to the barrel. This is where the problem lay. Once I got the bolts out the collar and shaft could only rotate together when I switched on the motor. I eventually got the shaft away from the gearbox, but the collar was very firmly jammed onto the shaft.

I spent a week heating, quenching, oiling, and tapping, several times a day. Whenever I went past. I eventually put the collar in the vice and hit the shaft with a sledge hammer. Gently at first, using a hardwood block to cushion the blow. Nothing happened, so I hit it harder, still nothing. Then I hit it really hard and split the wooden block! But there was possibly a little bit of movement – but only possibly. Was I imagining it? Another hard wood block, and another blow from the sledge hammer saw it definitely move 1 mm.! I dosed it quite liberally with RP7 and left it over night. Several days and 3 hard wood blocks later, the shaft was free.

I discovered that the grease cap on the collar was blocked, so the collar was badly corroded and had swollen up and jammed onto the shaft. The lubricating tube was so badly blocked I couldn’t clear it out. I decided that it was easier to drill out a new greasing tube through the collar to be able to lubricate the shaft into the future.

I welded up a new steel pug mill table/trolley on castors, so that I can move the very heavy pug mill around in the future. I made an under carriage to carry the vacuum pump together with the pug, so that I don’t have to move the vacuum pump separately. This will be our new/old white stoneware pug mill. I’m still waiting to get my hands on another 4” Venco vacuum pug mill for the buff/brown stoneware wood fire clay body. It’ll happen. I just need to be patient.

Bit by bit, slowly, slowly. We are getting everything back to where we were before the fire.

There is a huge sense of satisfaction in being able to take other peoples unused and non-functional pieces of equipment and bring them back into productive use for very little money, by more or less only using my own labour, ingenuity and time. I’ve never done this kind of thing before, so it’s all new to me. I’m just making it up as I go along. There isn’t anything in life that teaches you how to disassemble a pugmill with a seized shaft. I’m lucky. It all worked out well.

It’s an honour and a privilege to own and use these personal links and connections to my friends. There is so much embedded energy in these machines, it’s important to keep them going and avoid waste. it is a delight to see them working properly and being productive again.

We are so lucky to have such Generous, helpful and supportive friends.

Nothing is perfect, nothing is ever finished and nothing lasts.