Tool Time

Tool Time

If you’ve spent much time working on bikes, cars or any other mechanical devices, you probably have been confronted with damaged internal threads in an expensive piece of equipment. The threads may have been boogered-up by you or someone else, or maybe they were old and corroded. Damaged internal threads often can be cleaned up with a tap or a thread chaser, but you have to use precisely the correct one. The tool must be of the correct diameter, and are the threads metric or SAE? Coarse or fine pitch? Right-hand or left-hand? So, to be able to deal with just about any damaged hole, you need a very broad and expensive selection of taps from which to choose.

But not if the affected hole is between 5/32(4mm) and 1/2-inch (12mm) in diameter: You then could use an Internal Thread Restorer from ThreadMate.

These clever little tools come in two sizes-a small one that works on threaded holes from 5/32to 5/i6-inch, and a larger one that fits from 5/ifito 1/2-inch holes.

Each tool has a cutting tip at the end of an adjustable arm that is regulated by a knurled knob. You first fully retract the arm and insert the tool into the hole, then move the arm outward by turning the knob until the cutting tip engages the threads. If the threads are damaged

near the top of the hole, start the cutting process below that point, down in the good threads, then turn it back out to chase the damaged ones, if the damaged threads are nearer the bottom of the hole, insert the tool near the top and turn it inward to make the repair.

What’s especially useful about the Thread Restorer is that it works on any type of thread within the tool’s operating range. Doesn’t matter if it’s metric, American, left-hand or right; the tool works. Its cutting tip pivots freely enough to allow it to conform to any thread pitch or direction. Understand, though, that this is a thread restorer, not a tap; it can only repair threads, not cut new ones. Even then, the hole must have enough remaining good threads to serve as an accurate guide for the cutting tip. Each tool also comes with two yellow plastic sleeves that slip over the working end but leave the cutting tip exposed. The sleeves are used to prevent the backside of the arm from damaging the good threads in soft metals, such as aluminum or magnesium, while the tip is cutting the damaged threads.

Internal Thread Restorers are available from several tool suppliers, but I got mine online from Lee Valley & Veritas (www.leevalley.com). The Restorers sell for $32.50 apiece (part #27K07.91 for the small tool, 27K07.92 for the larger one), but you can get both from Lee Valley for $58.50 (part #27K07.99), a $6.50 savings. Replacement sleeves in packages of 5 go for $3.20 per package.

Nothing especially new or “trick” about T-handle hex (Allen) wrenches, but this eight-wrench metric set from Park Tool (part #PH-1; $60; www.parktool.com) has a combination of useful features. Each of the ergonomic handles contains a short, separate hex that lets you use the long shaft for leverage, making the job of loosening stubborn fasteners much easier. The five most common size wrenches (3,4,

5,6 and 8mm) have a little “speed bearing” on the shaft that you hold to spin fasteners in and out very quickly, which can be a real time-saver when a job involves a large number of Allen bolts.

Some other brands of T-handles also use similar bearings, but what makes these different is that the bearings are movable, held in place only by 0-rings. This permits the bearing to be easily shifted up or down on the shaft for user convenience or to clear an immovable component that otherwise might prevent the bearing’s use. What’s more, the long shafts of all eight tools have a ball-end that allows them to turn hex-head bolts even when an obstruction requires the shaft to be inserted into the hex at a slight angle. The PH-1 set also includes a plastic holder that can be mounted on a wall or a workbench.