All colonial surveying instrument makers had unique design characteristics to their sight vanes. These seldom, if ever, changed throughout their working careers. The dimensions, molding profiles, and thumbscrews with appropriate thread diameter and thread pitch were normally exclusive to a particular maker. To research proper sight vane fabrication, We use our database of original manufacturers specifications thereby insuring accurate dimensions.
Most importantly we match the patination of the newly fabricated sight vanes to the compass body. These sight vanes, once completed, will be virtually indistinguishable from the originals.
1. Each sight vane is engraved with a signature and date to prevent confusing historical data for future researchers.
2. We need to be supplied with the compass in order to fit the sight vanes and match the patina.