Drills and drilling

For drilling holes both the joiner's ratchet-bit or arm-brace with ball-bearing head (68:1) and the hand-drill (68:2) are used. The ratchet-brace is designed for slow, powerful cutting, usually with wing-bits having a square taper shank. The alligator jaws will also accept standard twistdrills with parallel shanks up to 3/8 in (9.5 mm) diameter, although they are inclined to slip under load if the jaws are at all worn.

This brace can be obtained in a range of sweeps, i.e. the circle through which the arm turns, from 8 in (203 mm) to 14 in (355 mm), with the larger sweeps yielding the greater power; while for confined spaces the electrician's ratchet-brace with 5 in (127 mm) sweep is invaluable. The standard hand-drill (68:2) is designed for the rapid boring of small-diameter holes, and has a three-jaw chuck accepting 1/4 in (6 mm) or 5/16 in (8 mm) parallel shank bits and drills. For larger shank sizes up to 1/2 in (12.5 mm) diameter the engineer's pattern two-speed drill with breast-pad for extra power is necessary. These hand-drills will not accept taper shank bits.

Was this article helpful?

0 0
The Complete Guide To Wood Finishing

The Complete Guide To Wood Finishing

Wood finishing can be tricky and after spending hours on building your project you want to be sure that you get the best outcome possible. In The Complete Guide To Wood Finishing you will learn how to get beautiful, professional results no matter what your project is, even if you have never tried your hand at wood finishing before. You will learn about every step in the wood finishing process from a professional wood finisher with years of experience.

Get My Free Ebook

Post a comment