September 2007 - Popular Woodworking Magazine

popularwoodworking.com
  • No tags were found...

September 2007 - Popular Woodworking Magazine

I stumbled on this revelation while drilling 3 ⁄ 4"holes in 3"-thick yellow pine with an auger bit.The task drained a cordless drill’s battery afterone or two holes. So I switched to a corded drill.After two holes, that drill caught fire. But thebrace with the same sharp auger breezed throughthe wood, and I barely broke a sweat.Here’s an anatomy lesson of a brace, and adiscussion of its most important features.■ The Head or Nave: The round knob at the topof the brace is properly called the head, thoughyou will see other names for it, such as “pad.” Itis made of metal, wood or a composite materialand should spin freely around. When you pickup a vintage brace, one of the first things youQuillNeckJawsHeadFlange of a fullyclad headHandleThrowRatcheting selector:forward, backwardand neutralChuckor shellFrameFootshould check is how well the head fits. A wobblyhead is an indicator that the tool is worn orpoorly made. The wobble will make it difficultto bore straight.■ The Frame: The U-shaped section of thebrace is called the frame, though sometimesit’s called the crank. The part where the framejoins the head is called the neck. The part wherethe frame joins the chuck is called the foot. Theplace you grasp the frame is called the handle.What’s important about the frame is how muchthe handle is offset from the head and chuck ofthe tool. Braces commonly have an offset from 3"to 7" – this offset is called the throw. Tools withmore throw can generate more leverage with lesseffort, but they require more space to work. If youtake the amount of throw and double it, you’vecalculated the sweep of the tool. The sweep isessentially the diameter of the circle created byturning the handle one revolution. The sweep isthe number that tool merchants use to describethe tool’s size. The most common sweeps are 8"and 10". The 6" size is good for small bits in tightspaces; the 14" sweep is good for holes that arelarger than 1" diameter in tough woods.■ The Chuck: The part that holds the bit is thechuck, and it is the biggest variable in a brace.There are probably hundreds of different designs.Most of them work fine for holding the tapered,rectangular tang designed for braces. But somechucks also will hold standard round twist andbrad-point bits, which is handy. The most importantthing to look for is that the jaws of the chuckclose tightly and don’t flop around inside thechuck, sometimes called the shell. Floppyjaws are usually a sign that the spring insidethe chuck is broken or dislocated. I’d pass ona brace with a broken chuck.Many chucks have a ratcheting feature,which is a lot like the three-position switchon a socket set. You can set the brace to turnthe bit only on the forward stroke, only onthe reverse stroke or during both forwardand reverse. While some woodworkers thinkthe ratchet is as unnecessary as socks on asquirrel, I disagree. The ratchet allows you tobore easily in tight spots where you can onlymove the handle through part of its arc, such asin a corner. Also, the ratchet allows you to easilyrotate the handle in one part of its arc that iscomfortable or requires less effort. One example:When working with the brace horizontal, it’seasier to push the handle to the floor (gravity isyour helper), and the ratchet allows you to workin that narrow band.The ratchet does add some weight to the tool,which some people dislike. But I don’t mind theweight. Most boring at the bench is done with thebrace vertical, so the weight isn’t an issue.The ratchet should move smoothly and click(just like a socket set) when engaged. In vintagebraces, the ratchet mechanism can get gummedup. On some tools it’s easy to clean and lubricatethese. On others (particularly the fine brace madeby North Brothers of Philadelphia) re-assemblingthe ratchet requires an engineering degree andan extra hand.Basic Brace UseBraces aren’t difficult to use. To load a bit inthe chuck, here’s the basic drill: With the chuckpointing up to the ceiling, grasp the chuck withone hand and hold the tool’s handle with theWhen boring large-diameter holes you canfatigue one set of muscles on the arm that isholding the handle. Instead, engage the ratchetand work only in the narrow area where gravity isworking with you.Cranking the jaws closed by using the handle isfaster than simply spinning the shell with onehand. Plus, you can get the jaws tighter on the bitwith less effort by adopting this technique.woodworking-magazine.com ■ 37


Critical axisNon-critical axisKeep your body as close to the axis of the braceas possible and focus your downward pressure onthe head of the tool. Note that the hand on thehandle is employing a loose grip.With many holes there is a critical axis thatrequires attention. If I stray left or right here, thisdoor stile is as good as firewood.Here’s the non-critical axis. If I stray forward orback then it’s no big deal. That can be correctedwith the next hole.other hand. Set the ratchet (if there is one) to themiddle position so it is disengaged. This is likethe neutral position on some ratchets in a socketset. Now crank the handle clockwise to open thejaws. Insert a bit between the jaws and close thejaws until they just barely hold the bit. Wigglethe bit until its rectangular shank finds its nestingplace in the jaws. Now crank the handle until thejaws close tight.To make a hole, place the tip of the bit in position.If you are boring with the tool vertical, then“The more a guitar is played, thebetter it will sound; it needs to get usedto being an instrument and not achair, so it’s difficult when somemusicians expect a guitar to playitself. That’s why I think most goodluthiers would make great shrinks:It’s usually not the guitar.”— Frankie Montuoroguitar technician for the band Wilco in"The Wilco Book" (DAR)do your best to get your body over the tool as muchas possible. I’ll frequently perch my chin on thehead of the brace. This increases accuracy.If you are working horizontally, brace thehead of the tool against your stomach or chest(whichever is more convenient).Now you want to begin boring. I like to assignseparate jobs to each of my hands. My dominanthand typically goes onto the head and graspstight. That hand has only one job: Steer straightdown. My off-hand goes on the handle – lightlynow – and has only one job: Travel in a circle.Mastering this basic stroke and approach tothe work is the first step to getting an accurateresult with a brace. The other tricks have to dowith all forms of boring, whether they are poweredby electrons or empanadas.Learn Plumb; Learn LevelWhile growing up, we first learned good postureby balancing textbooks on our heads and thenwalking around the classroom. To learn to boreaccurately, there are a couple good crutches tolean on until you get the feel for the tool. Theserules apply no matter what sort of boring toolyou have in your hands.Most boring is done at 90° to the work, so youcan teach yourself to bore true by sighting yourwork against a try square positioned on yourwork or your bench. You also can sight your bitagainst any layout lines scribed on your work,such as when you’ve marked out a mortise on astile. What’s critical is to figure out which axis ismore important to observe, and to then positionyour body (and try square) to take advantage ofthat knowledge.Here’s a classic example: Let’s say you are boringout the waste in a mortise in a door stile. Thestile is sitting on your bench and you are standingat the end of the board. The critical axis for thisjob is left and right. If you lean left or right asyou bore, the mortise will not be straight – or youmight even bore through the face of your stile.The non-critical axis is forward and back. If youlean too far forward or too far back, it’s no bigdeal. The next hole (or your chisel) can correctthat error. In some cases the error doesn’t evenneed to be corrected.So remember this when you bore: It is easierto sense whether you are listing left or right thanit is to tell if you are leaning forward or back.That should tell you where to stand and whereto place your square as you are training yourselfto work at 90°.But what about when you must bore at an oddangle? That is, anything to do with a chair or astool? You might not be able to train yourself tohit 17.5° off of 90° in your sleep, but you can train38 ■ woodworking magazine Autumn 2007


Extend your index fingerwhen drilling, hammering,sawing or planing.Your finger will helpbring the rest of yourbody in line.In critical boring operations, you can use a blockof wood that’s cut to your desired angle and pressthe flutes against the block.yourself to stay consistent once the cut has begun.Just remember that one hand steers and the otherhand cranks, and you’ll get the hang of it.When boring odd angles, you can use a slidingT-bevel as a guide, which is a help. But you alsocan use a friend to act as a spotter. Whenever Iget ready to bore something on the odd side, I’lltake one of three approaches.If it’s an angle that has to be dead-on, I’ll positiona T-bevel along the critical axis and have aSuppliesTools for Working Wood800-426-4613 ortoolsforworkingwood.comn Nicholson 7" Auger Bit File# ST-AUG, $9.80Brass City Records and Tools203-574-7805 orbrasscityrecords.comn Walt Quadrato is an excellent sourceof vintage braces and auger bits atfair prices.Sydnas Slootsushandel@msn.com orsydnassloot.comn Sanford Moss’s excellent web site is awealth of information on braces. Sanfordalso sells a fair number of bracesand other vintage boring accessories.friend or co-worker spot me as I begin the hole.(Once the cut has commenced, you’re committedand it’s probably better not to have peoplewatching.) If I’m alone in the shop, I’ll begin thehole with the lead screw of the auger only andtry to get the bit lined up against the blade ofthe T-bevel before I commit to burying the bit’scutting spurs into the work.The third option involves the miter saw. Set thesaw to make a cut that matches the angle you’reseeking. Cut a piece of 2x4 scrap at that angle.Then clamp or screw that scrap so the flutes of thebit ride the angle as you bore. This final approachisn’t as fussy as building a complex boring jig,but it does increase your accuracy dramatically.And remember, if you measure the angle fromthe underside of the stool or chair you can screwyour guide block directly to the work because anyholes from that process will be hidden.The above guidelines aren’t just for braces.They work with cordless and corded drills aswell. When dealing with drills that have a pistolgrip(corded or cordless), there is an additionaltrick to learn. When you grip the handle of thedrill, point your index finger out so it’s in linewith the chuck of the tool – don’t use your indexfinger as the trigger finger. That’s the job of yourmiddle finger.This little trick works with any tool thatrequires guidance (especially handsaws andjigsaws). Sticking your index finger out to pointthe way is a cue to your body to straighten outand head the direction of the pointer finger. Thismight sound like bunk. I swear it is not.Most early tools were designed for a threefingergrip and encouraged the user to extend theindex finger. Modern woodworkers who pick upthese old tools usually assume that the reason thehandle hurts their hand is that it was designedfor people back in the day when they had smallerhands. That’s just not the case. Study the oldbooks that depict hand-tool use and you’ll seeimmediately that extending the index finger iscommon. And, in fact, people weren’t that muchsmaller in the 18th century. Not to belabor thepoint, but if you’re interested in this myth, ThePlimoth Plantation in Plymouth, Mass., has anengaging article on this topic on its web site:plimoth.org/discover/myth/.Watch the SpursOnce you have the confidence to leave the trysquare behind as you bore (and your head hasbeen cleared of images of our forefathers beingtiny people), then try this other trick to check yourwork as you begin boring. When using an augerbit, the first part of the bit to bite the wood is thelead screw. It’s a simple cone and can’t help youWhen you are boring a critical hole, begin the cutcautiously so you can see if the spurs are enteringthe wood at the same time, which is a good sign.With this wayward bore, there’s still time to correctthe angle.woodworking-magazine.com ■ 39


with anything except making sure your bit startsat the right point. Whether or not you are plumbisn’t the job of the auger’s lead screw. Insteadyou need to pay attention to the spurs – the football-shapedcutters that rim the bit and score theoutside diameter of the hole. These spurs travelthe entire circumference of your hole, and youcan use that to your advantage.As the lead screw begins to bury itself into thework, watch the hole and advance slowly. Watchto see if both spurs hit the wood’s surface simultaneously.If the bit is angled off 90°, one spur willcontact the work before the other spur – assumingyour spurs are filed to the same height.If one spur plows across the wood before theother, then stop boring, release the brace and stepback to see where things are going awry. It shouldbe fairly obvious to your naked eye. If not, get outa square to see where you are leaning. With justthe lead screw engaged, it’s fairly easy to make aslight adjustment and get on track. But once bothspurs and the flutes of the bit are engaged, you’refairly committed to cutting that angle.But not always. Chairmakers commonly usespoon bits to allow themselves some wiggle roombefore committing to a particular angle. A spoonbit looks like someone split a metal pipe along itslength and ground one end to a rounded spoonshape. The rounded end allows the woodworkera fair amount of time to change angles as the cutbegins. I’m personally not fond of spoon bits fora few reasons. One, they’re somewhat rare. Theycut slower than an auger. And the inexperiencedborer is just as likely to wander off of a correctangle as wander onto the correct one.Engage the AutopilotThere are other tricks to drilling holes with precisionthat don’t involve a drill press. WheneverI have a hole to bore that must be located preciselyor involves combining bores of differentdiameters, such as when drilling for a bolt andits washer, then I almost always rely on a narrowpilot hole to guide all of my bits.A pilot hole is a good idea for a couple reasons.One, a small-diameter hole is easier to drill in aprecise manner than a large-diameter hole. Withsmall bits you can focus almost all of your effortand attention on boring true without worryingabout swinging your arm wide and throwingoff your angle.Once you get a pilot hole drilled, you can usethat to guide all of your other larger bits. The leadscrew or brad point of your bit will always wantto follow the pilot hole because it’s the path ofleast resistance through the wood.How big should a pilot hole be? You need touse some judgment here. Use the smallest-diameterbit possible for the thickness of the work youare drilling. Thicker woods will require bits thatare bigger and longer. For 3 ⁄ 4"-thick work, I’ll usuallychoose a 3 ⁄ 32" bit and work up from there.Once you get your pilot hole drilled, youshould drill the largest-diameter holes first – usuallythese are the counterbored recesses for thewashers, the nut or the head of a bolt or screw.For these counterbores, always pick a bit thathas some sort of well-defined point, such as aForstner, brad-point, auger or center bit. Gardenvarietytwist bits (designed for metalworking)don’t follow a pilot as well. Their blunt tips can bedifficult to start without first using a centerpunchon your work to dimple the wood.Place the point of the bit in your pilot holeand drill your counterbores on the entry and exitpoints of your pilot.With the counterbores complete, you can thendrill the hole that connects them. Again, choosea bit with a well-defined point. Place the tip inthe pilot hole in the middle of the counterboreand bore the through-hole. If it’s a particularlydeep hole, you can work from both entry and exitholes to increase the chance that your holes willline up just right in the end.How you stop the cut is almost as importantas how you begin it. When you bore through apiece of work, you can blow out the far side ofthe workpiece as the bit exits the work. You canprevent this blow-out by backing up the exit holewith a piece of scrap. But sometimes that’s notpractical, such as when boring into the middleof a board. So here’s another approach.Drive the bit into the work until the lead screwjust begins to poke out the far end of the work(mark your bit with tape so you’ll know when youare close to the final depth). Remember this: Stopboring as soon as you can feel the bit on the exitside. You want the exit hole to be really small.A small hole will make the next hole you makeeasier to bore accurately.Remove the bit from your first hole then moveover to the hole’s exit side. Place the lead screwof the bit into the small hole on the exit side andadvance the bit. It will cut a clean exit hole that’slined up with your first hole.Clear a PathDon’t, however, confuse pilot holes with clearanceholes. Their names give away their jobsin the shop. A pilot hole is designed to lead theway for something else that will then cut into thewalls of the pilot hole – perhaps it’s another bit,a wood screw or a cut nail.A clearance hole, on the other hand, is supposedto clear a wide path for something to followbehind, such as a bolt or a piece of hardware. Thedifference is important. A clearance hole shouldbe wide enough so the hardware doesn’t cut significantlyinto the walls of the hole. Whereas apilot hole should be small enough that the hardwarecan bite into the walls of the hole but bigenough to prevent the hardware from jammingand breaking.The most common (but misunderstood) applicationof pilot holes and clearance holes is whenusing a screw to fasten two pieces of wood. Let’ssay you are going to screw a top piece to a bottompiece. The best form of this joint is where youfirst drill a pilot hole through the top piece andWhen you need a hole that’s dead-on or steppedin size, consider making a pilot hole first to guideyour future drilling efforts.The pilot hole helps guide all subsequent boringoperations. For the counterbore, place the leadscrew in the pilot hole.When the lead screw poked through the exitside of this hole I stopped turning the handle,removed the auger and began the cut on the exitside. This eliminates the grain from blowing outas the bit clears your work.40 ■ woodworking magazine Autumn 2007


The Care and Feeding of Auger BitsClearanceholeShank Twist HeadTangFluteLead screwIn this cutaway, you can see how the pilot, clearancehole and countersink all work together toensure that the screw will pull the work up tight(left). And you can see an example of what bridginglooks like with the screw removed.into the bottom piece. The pilot hole should bethe same diameter as the shank of the screw (themetal part minus the threads). This is sometimescalled the “minor dimension” of a screw.Then drill a larger-diameter clearance holein the top piece only. The clearance hole shouldbe slightly larger than the entire diameter of thescrew (this is sometimes called the “major dimension”of the screw). Drill a countersink for thehead of the screw if necessary then drive yourscrew. This arrangement of holes will allow thescrew to do its job: The threads will bite into thewalls of the pilot hole and pull the head of thescrew down – pulling the top piece onto the bottompiece. If you don’t drill a clearance hole inthe top piece, the screw’s threads could bite intothe top piece and prevent the joint from closing.This is called bridging.With these basic skills in hand you will beprepared to move into one of the great unexploredrealms of woodworking: boring holes. Open anyold tool catalog or book from the 19th centuryand you will be stunned by the wide variety ofbits that were available to the woodworker.And though all the different types of bitsmight be bewildering, they all work on the sameprinciple. Take heart in that when Joseph Moxonpenned the first English text on woodworking in1678, he barely made mention of the brace, whichhe called a “piercer.”“Its Office is so well known, that I need saylittle to it,” Moxon wrote. “Only, you must takecare to keep the bitt straight to the hole you pierce,lest you deform the hole, or break the Bitt.”That’s all you get in the first-ever English bookon the craft. According to Moxon, the whole worldof hole knowledge is widespread and shallow. ButI actually think it goes a bit deeper. WM— Christopher SchwarzAuger bits are wondrous, efficient bitsof tooling. When sharpened, they eatthrough wood with little effort. Sharpeningthem is simple. The first rule is to sharpenthem as little as possible. Mimic all the anglespresent on the tooling and take as few strokeswith an auger bit file as possible. Here are theimportant parts of the auger bit and how tocare for them.■ The Lead Screw: If this is clogged, thebit will not advance into the work. You don’thave to sharpen the lead screw, but you dohave to keep it clean. If it’s gunky, I’ll soak itin some mineral spirits and then clean thethreads of the screw with some dental floss. Ifthe threads get worn or broken I pitch the bitand reluctantly spend another 25 cents on areplacement at the flea market.■ The Flutes or the Twist: These carry theshavings out of the hole. If they are rusty, theCutting lipTo file the cutting lip, brace the bit against apiece of scrap and rub the file against the lip. Afew strokes should produce a fresh edge.bit is more likely to clog. You can polish up theflutes with fine sandpaper if things aren’t toobad. Or you can spend another quarter. Keepthe flutes as shiny as possible. Wipe down theflutes with a little WD-40 or light machine oilwhen you are done with the bit for the day.■ The Spurs: These football-shaped cuttersscore the diameter of your hole. You filethem on the inside only. Filing the outsidewill shrink the diameter of the circle that theyscore and the auger will jam. Game over. Takea few strokes with an auger bit file and mimicthe gentle radius of the spur.■ The Cutting Lips: These two wedge-likeparts of the bit act like levers. They wedgethemselves under the waste that’s defined bythe spurs and force it up the flutes. File theirbevels, which face up toward the flutes of theauger. Five or six strokes will do. — CSSpurTo file the spurs, clamp the auger upright andgently file the radius of the spur. Never file theoutside diameter of the bit. Work the inside only.woodworking-magazine.com ■ 41

More magazines by this user
Similar magazines