An aerospace contract shop had an expensive problem – producing a front and back countersink by hand on a magnesium housing resulted in parts being scrapped. At $15,000.00 a part, the problem needed to be corrected more than fast.. Just to make thinks more interesting, the location of the countersinks on the part required over 14 inches of reach from the top of the tool to the face of the holder for clearance. Using a stock standard Defa front and back chamfering tool from Heule Precision Tools allowed the customer to machine the 90 degree countersink in their horizontal machining center, solving the problem. We provided specs to the customer to help them build their own extension, I’ve attached a few photos of the tool. Heule Precision Tool’s twin bladed Defa tool allows for adjustment of the chamfer diameter on the tool and allows for toleranced chamfers and countersinks from 4mm to 44.5mm.