|Borehole alignment device
|Developed over several years by Kevin Heywood, of Hanson Aggregates, the “Boremaster” is an optical device to measure the angle of inclination and azimuth of dry straight shotholes. It therefore serves as an easily deployed low-cost alternative to probe or bore-track systems. The patented system comprises a gimbal-mounted fluxgate compass that is tribrach mounted (similar to a theodolite) on an aluminium mounting tube inserted into the top of the shothole to enable perfect alignment with a powerful tri-LED waterproof torch shining up from the base of the hole. The mounting tube can be sectionalised for easy hand portability, though the tubing is of low cost and could be left a safe distance back from the active quarry crest.