Spring has arrived in Boston, and with it (if you'll forgive a little synaesthesia) a refulgence of aroma in the larder where most of my Pu-erh lives.
Appropriate technology department...Lots of talk on various lists about tools and techniques for deconstructing tightly compressed Pu-erh cakes. I've found that just storing most examples for a year or two in conditions of varying temperature and humidity loosens them up quite a bit. However, I also make frequent use of the two tools described in this post on Mr. Petro's site:
(If that doesn't work, just go to the Forums page and search the term "dissection" - it's that word's only appearance.)
I would stress that in my opinion, the success of these tools is critically dependent on their shortness. This allows the application of a great deal of force while maintaining good control, with nil risk of injury. (I was inspired to try this by experience with engraving tools, which work the same way.) The detailed finish of the blade tips also seems to help: a moderately (not extremely) sharp edge, buffed to a mirror finish.
When people ask about tools for breaking up an entire cake into chunks that can then more easily be further divided, I sometimes suggest an arbor press:
These are readily available at used-tool stores, and are quite adaptable in all sorts of ways. They are also fairly clunky. I've tried an antique book press (used to collect them); only the largest and heaviest models could deliver the needed force.
More convenient for the kitchen might be a gear puller:
These are small, light, cheap (under $20 new), and surprisingly powerful. I haven't actually confirmed the approach, since my gear puller seems to have gone walkabout. But perhaps some automobile enthusiast here would like to try. If anyone wants to buy one for the purpose, be aware that both two- and three-jaw versions are available. For square cakes, a two-jaw version would be preferable. Also, many have hooks that are too short to grip the rounded edge of a tuocha, so check that first.
Other recommendations, if someone wants to try: pick one with a fine-pitch screw, which makes it easier to generate a lot of force; and wipe off any loose oil to avoid contaminating the cake.
Hope this is useful to somebody out there.
-DM