Popular Woodworking 2009-08 № 177, страница 42

Popular Woodworking 2009-08 № 177, страница 42

Thi s is why I switch to a +5° cut ti ng angle for planingastack ol poplar drawerparts.

Setting the Cutting Angle

When tuning a bevel-up plane, there are three important angles to keep in mind: The beve!angleoftheblade,thebcdangleofthe plane, which is Ly pical ly 12°, and the cutt ing angle, which is the sum oFthe two previous angles. To modiFy the cuttingangle, just change the bevel angle (or better yet, just swap blades for one with a di fferent bevel angle), lt'sthateasy. By having three blades ground to different bevel angles, you'll in effect have three different planes for the price of one.

Knowingihe Limits

As I mentioned earlier, the range of cutting angles from which to choose is approximately 37° to 62° By now you may be wondering, if a 37° angle produces good resu 1 ts on e nd gra i n woul dn't a lower angl e be better still? Perhaps, just keep in mind that a 37°cuuingangle requires a 25°bevel angle. Lowering the bevel angle a couple more degrees will create a sharper cutting angle w ith a clea ner c ut an d less resist ance. However, a bevel angle below about 22° or 23° will probably lest the limits of the steel and the edge will likely fracture. Besides, a 37° cuttingangle will create wispy thin cuts on most end grain.

On the other end of the scale, creating a cuLtingangle beyond about 62° increases i he cutting re si stance to the poim that you'l I find it difficult lo push the plane. Anda62° cutti ng angle is sufficient forcreati ng a silky-smooth surface on challenging stock.

Other Bevel-up Planes

As 1 mentioned earlier, block planes and shoulder planes also have the bl ade in ounted bevel-up. So you can change the cutting angle to suit your needs by changing the bevel angle.

When I'm workingwood, 1 thinkofblock planes as sea led-down smooth planes, luse them for smoothing surfaces and leveling joints in areas where a bench plane would be unwieldy. Because I reach for block planes so frequently, I have a nu mbe r of the m a nd each is tuned for a different cutting angle. Also, keep in mind that block planes are availablein a low angle, 12° bed, andastan-dard angle, 20° bed. To trim a miter, it's best lo choose a low cuttingangle. You'll get the

lowest cuttingangle by startingwitha plane that has a low bed angle. To create a high cuttingangle for smoothing, 1 use the standard-angle block plane with a 20° bed and grind the blade to 40° to create a 60°cutting angle. Thissetupallowsme to smooth a tiger maple post block on a dressingtable without the slightest risk of tear-out.

As the name implie s, shoulder planes are designed for trimming tenon shoulders to improve the fit of the joint. And although they work great for fine-tuninga shoulder, Idon'tlimitthemtothat. In fact, loflen use shoulder planes for smoothing away mi 11 ma rks i n rabbets on a 11 pped d rawer or door

prior to applying the finish. So I have one shoulder plane tuned with a low cutting angle for trimming end-grain shoulders and another tuned with a high cuttingangle for smoothing long-grain rabbets.

Once you experience theresultsyoucan achieve by using different cutting angles, you'll start finding other applications for this concept. 1 even have paring chisels Lhat I've ground to 60°. But that's a different article. PW

Lonrne Bird runs the Lonnie Bird School of Fine Woodworking donniebird.comi and is the author of "Taunton s Complete Illustrated Guide [o Using Woodworking Tools."

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Other bevel-up tools. Block planes (foreground) are ideal for trimming chores and planing end grain. Shoulder planes (background) adjust tenons, rabbets, half-lap and bridle joints. Both types of planes harness all the powers of bevel-up smoothing planes and allow you to easily change the cutting angle for different chores.

High-angle shoulder plane. I keep this shoulder plane sharpened at a high cutting angle to handle long-grain rabbets, especially in figured material.

48 m Popular Wood working August 2009