Tuesday, April 27, 2010

Learning to Plane - Part II

Last weekend, my friend Jeff Fleisher and I attended a two-day workshop on hand planes at the Marc Adams School of Woodworking.  The class was taught by two leaders in the field of hand planes, Thomas Lie-Nielsen, founder and owner of Lie-Nielsen Toolworks, and Christopher Schwarz, editor of Popular Woodworking Magazine.  The classroom held 20 Lie-Nielsen workbenches and provided comfortable room for about 40 of us to do our work. 

The class was a combination of lectures by the two presenters, hands on work on sharpening, setting up and using our own planes and those brought by the presenters, watching a film about the Lie-Nielsen factory and the making of their planes and other tools and a planing contest.  Lie-Nielsen had a full complement of their planes on hand for us to handle and try out and took orders from those who decided to purchase one (or more).  Chris Schwarz also brought a lineup of his own personal planes that we were free to use.  And Chris's Lost Art Press had T-shirts, hats, books and DVDs for sale.

I brought all my planes, including a new Lie-Nielsen low-angle jack plane I bought only a week before the class.  During the class, Tom Lie-Nielsen signed tools of his manufacture with an engraving tool.  I had all six of mine signed.


A major portion of class time was devoted to sharpening.  Sharpening is, after all, the essential step in getting a plane to produce consistent, thin shavings of the type we all desire.  Our presenters taught a method based on David Charlesworth's, but simplified.  They did not argue that their system was the best, only that it worked.  Chris said all systems work and that we should pick one system of sharpening and stick with it for a while, that our edges would improve over time.  Don't be a "sharpening bigamist," he concluded.

An edge is when two planes come to a point.  The smaller the point, the sharper the edge.  Also, the more you polish the edge, the more durable it will be.  On the other hand, there is a tradeoff; the thinner the edge, the more fragile it is and the more often you will need to sharpen it.


The back or face is the flat side of the plane blade, the bevel is on the other side.  Only the ends of both sides need to be sharp.  Except on high quality planes or on blades needing reworking, you grind the bevel.  The bevel can be flat or hollow ground.  Regrinding will be needed after a blade has been honed five or six times or the secondary bevel gets too wide.  It can be done on a grinder, but we used 80 and 120 grit sticky back sandpaper on a flat surface to shape our blades where needed.  Only one of my blades needed grinding. 

After grinding, the next step is polishing the ends on both sides of the blade.  First you flatten the back of the blade.  Chris does this on a 1000 grit stone and does not polish the back any higher.  There's no need to.  The goal is to assure the blade is flat.  Once it is, you move on.  

Back Bevels

Chris strongly supports the use of back bevels--secondary bevels on the back of the plane that increase the sharpness of the edge--on all blades except chisel planes.  These can be used with both bevel-down (traditional) and bevel-up planes.  He uses Charlesworth's "ruler trick" to create these.  This involves taking a thin ruler (he uses Lie-Nielsen's ruler), placing it on the near edge of the waterstone, then, with the edge of the blade a half-inch off the far edge of the stone and flat against the ruler, pulling it onto the stone and rubbing it back and forth a few times (say 10) on each of the three grits (1000, 4000 and 8000).

Secondary Bevels

Precision in setting the angle of the secondary bevel is not critical, but consistency is.  Chris uses a homemade jig to set the proper angle at which the bevels will be honed using a simple $12 honing tool.  Typically, the secondary bevel is honed at 5 degrees higher than the primary bevel.  David Charlesworth also advocates a tertiary bevel, but both Chris and Tom thought this to be unnecessarily complicated.  Chris uses each of the three grits to hone the secondary bevel.  He prefers Shapton stones because he travels a lot and they don't have to be soaked like the Norton stones do.  Another class member told me the Shapton stones also wear better than the Norton stones.  Chris uses a DMT diamond stone (coarse or extra coarse only; finer stones use a different method to adhere the diamonds that is undone by the waterstones) to dress his waterstones flat.

Honing Guides

He prefers the inexpensive type of honing guide that grips the blade by the sides.  These may require some filing to assure the blade is held flat.  But in his opinion they work better than the type (like the Veritas Mk. II) that hold the blade from the top because the latter can allow the blade to slip out of alignment.  Lie-Nielsen provides instructions on building a jig like Chris's for setting the angle of the blade in the honing guide.

Straight Blades

You begin sharpening by honing a straight secondary bevel.  You take about 10 strokes with the 1000 grit stone so you get a bevel that is consistent all the way across the blade.  You want all the scratches from the primary bevel removed.  Pull the blade across the stone with heavy pressure, then a few light pulls using the slurry created by the heavier pulls.

Next go to the 4000 grit stone and hone in a back and forth motion about 10 times.  The steel wool-like pattern from the 1000 grit should disappear and a bright line should appear.  Many woodworkers stop here.  The edge will be fine, but it won't be as durable as if honed on an 8000 grit stone.  When using the 8000 grit stone, a Nagura stone is not needed with Norton waterstones.  Lighten your touch with this stone.  Use a back and forth rubbing motion.

Next we learned how to create cambered bevels.  I'll cover this in my next entry.


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