Distinguishing between PMC+ and PMC3
By Lois Lynn
Editor’s note: For our readers just meeting Lois, she is a PMC artisan who last worked with PMC when the only PMC products on the market were the original formation and PMC+. Lois spends a little time getting to know PMC3 and thinking about when each variety of PMC might be the best choice for a project. In doing so, she utilizes a simple testing method that is useful when comparing the properties of any metal clay with another.
Lois talks about the “hand” of clay – a term borrowed from the world of textiles and useful in discussing many materials. What is the hand of fabric (or clay)? The best definition I found was “The sum total of the sensations expressed when a textile fabric is handled by touching, flexing of the fingers, smoothing and so on.” In essence, the clay's "personality."
In my last post, I detailed my exploration of PMC3 making an object from wood clay with embellishment and then comparing it with an object made in the familiar (to me) PMC+. As I stated in the June post, I did find differences between the clays, but I feel I still need to compare these two further as I’m not clear on the hand of each when forming and handling them. Are there differences and will the way each handles affect the artist’s methods of construction and finishing?
To determine whether there are differences and if the differences prove significant to the making of a final product, I set up a very simple experiment. I fashioned an uncomplicated form from both clays so the differences between the two would be more obvious.
I divided six grams of PMC3 into three parts, each part smaller than the one before. I created a “handle” to grip the clay on each and teased each into a tear-drop shape. I placed a hole in each “handle” and added a small CZ’s to each. I repeated this process with PMC+.
I fired all of my test pieces together at 1650 F degrees for an hour to increase their strength and durability. After brushing and tumbling, I mounted them on a chain mixed with “cornflake” keshi pearls I harvested from an old necklace. I added “found” pearl findings to complete the look.
I like the flash of the CZ’s…it helps draw attention to the earrings. I was looking for a very natural, soft look. But once I had the earrings constructed, I wondered if the PMC pieces may need a little antiquing to make them stand out a bit more…give the overall effect more dimension. I’ll wear them awhile without antiquing before I make that decision - let the soft effect have a bit of time so as to give it fair consideration. I may try antiquing just one earring or just around the CZ’s to make them stand out and then make the decision.
So what did I learn about the clays? The PMC3 is a bit stickier and handles more stiffly. It seems more cohesive, good for keeping the form in one piece and shape retention, but its cohesiveness makes it more difficult to tease the desired simple shape from it. The material doesn’t have as much give. I also found I have a little less work time before the clay starts to dry.
I found the PMC+ has a slight advantage in creating the teardrops. It has a bit more fluidity and give to it. Pulling the shapes from the “handles” is a bit easier and the shapes seem to be more rounded and pleasing to me. Good if you’re experimenting with shape and testing the medium, bad if you want the initial shape to hold while manipulating it.
The PMC+ does shrink a little more as the pieces made from them are consistently a bit smaller than the PMC3. The CZ settings hold up about the same in both clay types. Other than that, the two clay types seem to be comparable as far as manipulating them.
These are very subtle, small differences, not really important unless you’ve used one of them for a long time and suddenly find you have to use the other, as I did during certification. There were enough differences between them to throw me off at the beginning but I quickly adjusted.
I feel I do have a good sense of both clay types now, so next time I think I will be trying a more complex project using PMC3 exclusively. I’ve been wanting to make an antique-style ring for awhile, so I think that will be my next project. It’s a rather complicated and precise design with construction challenges, so wish me luck!