Vulcan is not the god of rubber
Posted by Martin on June 3, 2008
Tonight I got a full update from Peter F. about the repair work on his vulcaniser. I’m not going to go through all the gory details here but I will summarize the salient points.
The most important fact is that the vulcainser is fixed and Peter is now is a position to restart mould making for the Saxons. There were indeed problems with the heating elements and Peter got the spare parts and completely stripped down vulcaniser and replaced them. He also noticed a number of other potential problems during the refit: worn heat resistant cables were replaced and a new thermocouple (heat measuring probe) was fitted.
These repairs seemed to cover all the bases yet the first attempts to make new moulds still didn’t go to plan. Given that the vulcaniser was fixed, that left only the rubber used to make the moulds as the potential problem. Sometimes old rubber won’t flow properly around the undercuts on master figures leading to poor definition so Peter tried again with a fresh batch of rubber. Alas, this led to the same unsatisfactory results.
At this point Peter started to suspect that his supplier of rubber (who he’s used for ten years) has changed the formulation of its product. So he experimented with rubber from a different supplier and that did the trick: perfect castings from this mould. Hurrah!
Of course the vulcaniser did have problems and it’s probably just as well that Peter has given it a thorough overhaul but he hadn’t anticipated difficulties with the rubber itself. Now, hopefully, Peter can get stuck into making a complete set of moulds for the Saxon musketeers using the new brand of rubber.