Restoration on the Spanish mortar bed is complete for the time being. We're now gettng ready to fire it with spherical shells (we don't have these yet.) We're looking into several options including somehow building up US 9-inch Navy shells to the proper diameter for the Spanish mortar (nearly 9.5 inches.) Another option is to fill basketballs with concrete, since a basketball is about 9.5 inch diameter. We have to find a method of supporting the basketball until the concrete sets, so the ball won't become eccentric due to the weight of the wet concrete. Making an iron or steel mold for cored zinc shells has been considered also, but we haven't yet found a machine shop that will do this for what we think is a reasonable price.
Here are some photos of the restored mortar with some of the original bolts and wood in the foreground of the last pictures. We used over 110 board feet of aged walnut to make the two wooden transoms and the bolster (supports the barrel at the proper angle of 45 degrees.) The bolster is the only piece that did not come out correctly and will eventually have to be re-done. Fortunately this is the smallest of the three wooden parts of the bed, and can be removed by removing two long bolts that sexcure it to the forward transom.
We're also looking into stabilizing the surface of the mortar barrel so the oxidation you see on it now cannot progress. Most guides I've seen recommed cleaning the surface of the bronze, using certain chemicals if needed, then coating it with wax. There's quite a bit of material you can find under the topic "bronze disease."
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