Damaging the engraving on screw heads is not an unwarranted concern, but if you use real brass drifts, made for the purpose, and not just a hunk o some yellow bar stock, you will very hard pressed to hurt the engraving. If you have round screw heads, use the appropriate concave punch, if they are like Parker lock plate screws, Flat, use flat punches. The important thing is that they are full face contacts.
I was always taught, and have learned by experience, that striking a screw head, or even a bolt, directly, can bend the shank. As many have learned, using the wrong screw driver, the material used in old screw stock is not very hard. A proper drift is held perfectly in line, axially, with the screw, and even if the mallet taps the drift off-angle, the energy is transmitted, through the drift in-line.
Even a screw whose head is not fully out of a countersunk hole can be bent, and visibly too.
Like the better screw driver sets, a good assortment of brass drifts and punches can number several dozen.
Old gun oil is like cement, and if you have to use any more than a few taps, you're better off with some Kroil or PB, applied right on the joint. Neither will hurt wood, but don't get carried away with the stuff either.
|
Threaded Mode