![]() You can make as many moulds as you have resin and sand for and they will store for quite a long time, years in fact if undisturbed. There's no need for flasks, even those snap flasks when pouring the metal. The advantages are that it's fast: cycle times can be as low as two minutes from mixing to tipping the cured mould out of the pattern. A barge load would fill a vacant lot and require a dozen or so 10 tonne tip trucks making multiple trips to unload, taking care not to fill the truck's bin more than a quarter of it's volume as the weight would blow the tyres if completely full due to the 1.5 specific gravity of the dry fine sand (it was often wet). Originally the sand was loaded by barge onto the ships and it was possible to get a cheap barge load when barges came South for maintenance at the local shipyard. The other local advantage was access to high quality super pure silica sand from a mine that supplied Mitsubishi with it's sand for glass making and foundry purposes. So the local demand is not there for an expensive product with a short shelf life. These days there's no real importer and any company importing the stuff wants to sell a minimum of two x 1000 litre IBC containers of a product that degrades within six months on exposure to moisture in air and probably UV light too. There were a few special conditions at the time that made it practical: there was enough domestic foundry demand from manufacturing for the resin to be imported in decent quantities to be fresh and for the supplier to be willing to sell small quantities. The guy I'm learning from has used it since the 1980's and at the time it had such clear cut advantages that he stopped using green sand completely. This is just a loose collection of my experiences with using phenolic urethane resin sand binder for mould making in a small non ferrous foundry environment.
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