Good news I hope for anyone wanting to take advantage of the properties of Jesmonite but unwilling to pay such an inflated price! For some time now I’ve recommended using Tiranti’s Plaster Polymer liquid together with a regular ‘alpha’ plaster such as Crystacal R or Basic Alpha. Similar results can be achieved with these at less than half the cost of the Jesmonite system. But recently I had the chance to test Specialplaster’s own SP201 acrylic polymer, with very promising results .. this time for less than a quarter of the price! I’ve written up these tests in the ‘Worklog’ at the end of Polymer-modified plaster in the Materials section under ‘casting’. I’ve also looked into whether the liquid and plaster components of Jesmonite can be combined with others, i.e. using the Jesmonite ‘powder’ with a different polymer or the liquid with other plasters. Judging by the few tests I made the answer is ‘yes’ .. but with some surprising results!
These are photos from the ‘Worklog’ featuring a mould jacket I made using the SP201 and Crystacal R plaster, reinforced with jute scrim. I took the risk of using only two layers of jute scrim, because I wanted to see how this compared to Jesmonite for strength. As it turned out it was more than strong enough, even though the shell can’t be much more than 3mm thick!