What do these bits look like? How wide are they? How does the drilling work, are they hollow and the material goes in the middle, which you then pull up every now and then? Do they come in sections (how long) and you just keep putting in more?
Sorry for many questions just can't find much info on actual field truth (just generic info on theory of operation).
Sorry for many questions just can't find much info on actual field truth (just generic info on theory of operation).