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.