47 - Build Your Own Mortising Machine , страница 30
Talk TOOLS OF THE TRADE Jacobs PowerCollef■ Change a router bit without fiddling around with wrenches? I was intrigued. This new collet (called a PowerCollet) tightens and loosens using hand pressure only—yet it holds bits securely. At least that's what I'd heard. But would a "no-wrench" collet hold a bit tightly enough to keep it from slipping? To find out, I decided to buy one and give it a try. The collet I bought fits a Porter Cable router. But collets are also available for a number of other routers. Note: The PowerCollet is manufactured by the Jacobs Chuck Company, and it sells for about $45. (For Sources, see page 31.) mount collet. It took just a minute to remove my original collet and tighten the PowerCollet on the spindle, see drawing above. But the PowerCollet is a little bulky. So to accommodate it, I had to install three metal spacers to extend the base of the router. (The spacers are provided.) locking sleeve. With the collet in place, it's easy to see how it works. There's a locking sleeve that snaps up and down to tighten (or loosen) a router bit. Note: I found it easiest to remove the router base when changing bits. k To adapt the V2'1 collet to a router bit with a 1A" shank, slip a sleeve (included with the collet) onto the bit. When you snap the sleeve away from the body of the router, the collet is in the "open" position, see Fig. 1 below. To do this, place your thumbs under the sleeve and give it a firm push — the collet snaps open with a click. insert bit. Now simply insert the bit in the collet, see Fig. 2. You'll feel some resistance here. That's because the bit has to slide through a rubber O-ring that seals dust out of the collet. tighten collet. To tighten the collet around the bit, you have to snap the sleeve toward the router. This takes some getting used to. Not because it requires a lot of pressure. But because the pressure has to be applied straight down in a quick, firm motion. I got better leverage by placing the thick part of my hands on top of the sleeve, see Fig. 3. There's one thing worth mentioning here. If you leave the base of the router on (or you mount the router in a table), you'll have to press the sleeve down with your fingertips. That requires quite a bit of finger strength. a test. Tightening the bit in the collet is one thing. But does it stay tight? By plowing deep grooves through hard maple, I got the answer I was hoping for. The collet held the bit tightly in place without any sign of slipping. conclusion. All in all, I was impressed by the PonverCollet. It makes changing bits fast, and it grips them tightly in place. I only have two quibbles. The sleeve is a bit stiff — and so is the price. & Hotei PowerCollet shown in closed position Nut secures PowerCollet to spindle Locking sleeve snaps up and down to tighten (or loosen) bit fbwerCollet (Cutaway View) Upper end : collet is tapened to fit in router spindle Lower end of collet squeezes shank or router bit. Upper ball bearing assembly locks collet In closed position Flat springs tension upper ,bal! bearing assembly Lower ball bearing . assembly applies pressure to collet Metal spacer Rubber O-ring extends seals out dust base PUSH UP ON SLEEVE TO OPEN COLLET MOTOR HOUSING LOCKING SLEEVE O-RING NOTE: TO APAPT COLLETTO FIT SMALLER PITS, SEE MARGIN INSERT BIT IN COLLET 30 ShopNotes No. 47 |
