Popular Woodworking 2008-10 № 171, страница 36
Capture the cutoff. aitoffof nearly 6' is ikt captuird by.»traditional splitter or >mtikkk-batk fingers, bin a ruing knife positioned dose to the bl*le uwdd keep the cutoff auuyfrom the tuck of the spinning Hade.
saw table. They- do not move once they arc installed. Standard splitter/guard systems can vary in how close the splitter is located to the blade, but can be as far back as 2" or more. The larger the gap between the splitter and the blade, the more potential there is for a piece of stock to come in contact with the back of the blade. Be mindful that with a static splitter, the gap will vary as the blade is raised and lowered. Static splitters must also be removed when making non-through cuts.
A better type of splitter is one that is ikk connected to the enclosure or top guard, but is conncctcd to the arbor casting itself. On European saws this type of splitter is called a riving knife. It is located just barely behind the blade and will raise and lower with the blade. The gap between the two never changes and is typically as close as 'A*. A good riving knife is set just a little lower in height than the are of the blade. This allosvs you to make both through and i»on-through cuts, which makes you safer ami more productive. Raving knives should not be used with dado or moulding-head cutters. For the record. I would much rather hase a nving-knite type ot'splitter on my saw.
Anti-kickback fingers are son»etimcs referred to as non-kickback fingers, dogs or pawls. Their job is to oppose the tendency of the saw to pick up material and throw it toward the oper
ator. Overall. I'm all for any thing (hat can make a saw safer. From an engi-nccring point of view, anti-kickback fingers seem to be a good concept but the)1 conk- with quite a bit of controversy as to their effectiveness. European saw manufacturers don'r use them at all because they deem them to be virtually iiK'ffcctive with little positive gain. As a matter of fact. European saws can't have anti-kickback fingers because of the dynamics of a riving knife. Anti-kickback fingers can sometimes get in the way. For example they can limit and even interfere when ripping narrow stock. I've had on nuiiK-rous occasions the anti-kickback finger limit the motion and even obstruct my push stick.
A splitter is a nice safety addition to a crosscut sled. However, you will have to remove your anti-kickback fingers if you use a splitter with your crosscut sled because they will create a hang up when you pull the sled back after the cut. Although anti-kickback fingers do work when using a miter gauge for crosscutting. they ate virtually useless with stock less than 6" wide. Remember: A standard guard/splitter combination is set back from the blade, whkh causes the anti-kickback fingers to be positioiKd even farther from the back of the Made. When crosscutting. the cut is compktcd when the trailing edge of the board clears the front of the teeth. This will leave the unsupported cut-off board right next to the back portion of the blade and just before the anti-kkkback fingers. Because anti-kkkback fingers are attached to the splitter, they follow the same rule for through and non-through cut applications as the splitter.
In the iK'xt issue I'll be discussing in detail one of the most serious safety problems with taMe saws: kickback. And I'll discuss hosv you can prevent it. PW
Marc is the fojoOe and o»f* 0< WW Marc Adams School cA VNtax>»orking. the largest woodworlung school n North Amonea. For more information on the school and its c>c«4ent CurncsAxn. mrt irotcaaarn.com or 317-535-4013 You can download ■ hit oiutetyru-M (or the table saw by wsftng populafwoodworkinfl.
Work with More Accuracy (and Safety) in your Woodshop
The best way to use your machines is rarely explained in the manual. Find out how to operate machines to get accurate results without sacrificing safety.
IN PAST ISSUES
Leam the Skills to be Safe
The gnxviduwkfrr a hfrtime of activate uwJuvrfaiig if to understand yxa kvis.
• Part 2 Practical Safety Devices
Chis>se the right guards, push sticks and hoU-Jounis to uvrfr softly.
• Part 3 Power Jointers
.\fatl people use dteir jcmlcrs unity;, trnihiirf in uurptd stok and unsafe opetau>tis.
• Part 4 Miter Saws
Stock miter sairs art neither oenrrMe or safc. Here's hew k>fix kihprMems.
•Part5 Band Saws
IkmJ sous are safc if used tormrly; hownrr k's easy to step oxrr the Hue and get bit.
•Part 6 Planers
ftwmn/ planers seem Mr soft Mxhittcs uiitH )\<u start testing their
poyulirwcvOwofWin* torn ■ 51