No sooner had I delivered a consignment of new the NGY ballast wagon kits to John of the FR shop than he placed an order for another run of the B wagon and DZ wagon kits which are selling well at Harbour Station. (A slice of the profits from each kit go towards steaming Welsh Pony remember)
The first task was to run off a set of moulds. It's a little different this time because my supplier has changed to a different brand of RTV rubber. The new stuff sets in a rather fetching shade of salmon pink.
It is not the silicone which is pink (it comes as a slightly off-white gloop) but the catalyst which is bright red as opposed to the previous stuff which was clear.
It's a quite a bit easier to use on account of the recipe calling for a 10% dose of catalyst instead of 5% which means on a 30g mix you're aiming to measure out 3g of liquid rather that 1.5g and so on. Unless you've borrowed some scales from the local laboratory its always going to be easier to accurately measure out a larger amount on the el cheapo catalogue shop digital scales I use.
The other advantage is you can see how thoroughly the silicone and the catalyst have been mixed together - if there are still any pale streaks in the pot keep stirring.
The test will be how well the moulds stand up to production line casting.
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