Many potters and ceramic artists are faced with the constant chore of recycling scrap clay and some even choose to mix their own clay bodies from scratch. Clay mixers and pugmills are great machines designed to help with these tasks in a variety of settings. They’re not cheap, but in some situations, the investment is well worth it. If you have wrist problems or have an intense production schedule, a clay mixer or pugmill could end up paying for itself in the long run. Among the major manufacturers, there are literally scores of options available, so you would be wise to do some homework if you are thinking about making this purchase.
Today, Bill Jones, editor of Pottery Making Illustrated, presents six important considerations to make when shopping for a clay mixer or a pugmill. – Jennifer Harnetty, editor.
Clay Mixer, or Pugmill, or Both?
An example of a horizontal mixer. The hopper on this model from Bluebird Mfg. tilts forward to aid in emptying the machine once the batch has been mixed.
What do you need? If all you want to do is mix your own clay, you need a mixer at a minimum. If you want a mixer that empties itself, go for the mixer/pugmill or a mixer with a tilting hopper. If you need clay that’s ready to throw without any further wedging, you’ll need a de-airing pugmill either as a standalone machine or as part of a mixer/pugmill. If your concern is just recycling, a pugmill or a mixer/pugmill can do the job but you’ll need to ask the dealer about what condition the clay has to be in before it can be processed, for example, stiff, bone dry, slurry, etc.
You don’t want to overestimate your needs and purchase a machine you’ll only use once or twice a year, or one that won’t keep up with your requirements. Manufacturers make machines of varying capacities and rate them by batch-mixing sizes (in pounds), mixing rates (pounds/hour), and pugging rates (pounds/hour). In addition to these rates, you’ll need to consider times for batching, unloading and wedging to get an idea of total clay throughput.
If you’re planning to mix clay, you’ll need a ventilation system to control dust even if the clay mixer has a tight fitting lid on the hopper. There are dust collection systems available or you may have an existing system to tie into. Caution: Even with a ventilation system, you’ll still need to wear a respirator when working with dry materials.
Larger machines have larger motors and hence draw more power. And if you opt for separate a separate mixer and pugmill, you’ll need to allow for two machines. Find out how much service you have (in amps) and whether your system can handle the additional draw (this is not usually a problem, but worth knowing in advance). You’ll also need to know whether you have single phase (residential) or 3 phase (commercial/schools) service as this affects the type of motor.
Cleaning and Storage
When switching from dark to light clays, or buying a machine without a tight seal, you’ll need to clean the machine. If this is a concern, check on how easy it is to dismantle the machine for cleaning. When storing a machine for days or weeks at a time, or even over summer holidays at schools, most machines can just be sealed and the clay inside remains moist.
All machines are potentially dangerous and pugmills and mixers are no exception due to the tremendous torque required to blend and move clay. Most machines are equipped with safety shutoffs and guards that prevent hands coming in contact with moving blades and augers. Check and compare safety features.
For more information
Soldner Clay Mixers by Muddy Elbow Mfg.
Note: Many manufacturers sell their machines through a network of distributors. Check the websites above and with your local supplier.