A boring head is a tool mounted in a mill or jig bore, used to create precision diameter holes. This will certainly be used for the Steam Engine and the Ironworker.
By adapting a 3" boring head, it is possible to bore up to 12" diameter holes ()
Most bores are precise to .001", but precision bores exist which can be much more accurate.
The tool can deflect if the boring bar being used isn't thick enough, so larger holes may require thicker boring bars to maintain accuracy. Many folks recommend a 3/4" minimum if doing larger holes.
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