Saturday, January 7, 2012

Best hand-plane results from sharp & square blades

Most people with a tool box own a plane and a chisel.  And yet of all the tools in those toolboxes, the plane and chisel probably get the least amount of use.  If this state of affairs sounds familiar, then read on!

When I fist started woodworking, I was, like many, the proud owner of an unused plane and an unused set of chisels.  I figured I was one of a "new breed" of woodworkers who simply relied on today's power tools to make furniture.

Such are the crazy things one can come up with when one is self-taught!

Now that I have a couple of years under my belt, and I've finally started making fine furniture,
I find myself reaching for my chisels and planes every day.  In many cases where I would have powered up my jointer, drum sander, or router, I now leave the power tools unplugged, and enjoy working faster, more quietly, and more safely, by using these traditional hand tools.

But I didn't understand hand-held knives until I understood how to sharpen them.   Planes and chisels simply don't work if they're dull.  For the novice, this fact isn't obvious: 'my results are probably bad because my technique is bad'.  In fact, if a plane or chisel is sharp and properly set & shaped, both tools are easy to use, and produce results far finer than any power tool can accomplish. 

This post is about sharpening, setting, and using planes.  Almost everything in it applies to chisels as well, though I don't cover chisel technique.  The methods I'll discuss were learned from my experience making furniture and lifestyle products from wood, and from books.

If you like, you can read about the three books I used to learn about planes.

Why hand plane?

Hand planes have been in use for at least a thousand years.  While they have been replaced by a host of lower-maintenance, more forgiving tools, they remain the fastest way to achieve some very common woodworking tasks, and they do it in such fine fashion the quality is hard to replicate any other way.  Planes remain the best at these tasks because of the way they cut, which is fundamentally different from power tools.

Plane blades are pushed through the wood, cutting in a long slicing motion.  The resulting surface is perfectly smooth.  Perfectly smooth wooden surfaces have a sheen and figure that is simply impossible to achieve in any way other than shaving the grain in one long slice.  Many woodworkers (myself included) spend far too much time trying to achieve this smoothness by other means. In fact, the entire woodworking industry has grown huge on other means of achieving what a hand plane does naturally.  

To straighten and chamfer a decorative wooden edge, I can either plane it in, or go through the following mess:
  1. First stop, the jointer, where I connect the dust hose, put on the earmuffs, goggles, and mask, and watch my fingers like a hawk.  The jointer leaves a wavy surface (no matter how slowly I go), and snipes the end of my board.  Good thing I left a little extra on the sniped end...hope I won't need to see the jointer again, after I cut the piece to final length...
  2. To remove the wave, I can either plane it off, or:
  3. Start sanding!  I might try a power sander, but the risk of creating a divot or angle is significant.  So I go with a sanding block: 120, 150, 180, 220, 320, 400...is it smooth enough yet?  Not as smooth as the stuff in the MFA.  And woops, I got a little angle going after all.
When it comes to flattening large surfaces, trying to get around using a large hand plane is a funny-looking clusterf***, made tolerable only by the joy of working with tens of thousands of dollars in noisy, dusty, gigantic machines.  All can say about that is: I'm glad I discovered the world of sharp planes before I went too far down the "Timesaver" road of dual drum sanders and super-wide planing machines.

Of course, giant drum sanders and their kin have their place, especially in a production shop where neither the maker nor the client cares about the superior look and feel of truly smooth surfaces.  But if you're going to sand your way to smoothness, know this: sand paper can't ever make wood smooth.  The best you can get is very fine scratches, and for those, sanding through the grits can take a very long time. 

Sharpening Planes

Sharp, square, flat blades are a must.  The plane needs to be able to take a very fine shaving from the wood, with little effort on your part, and the shaving needs to be of even thickness, tapering to nothing at the edges.  (In the photo at right, I need to adjust the plane blade angle slightly left, since the left edge of the shaving is too strong.)

When I first faced facts and sharpened my plane and chisel blades, I had a long hill to climb.  All of my blades had been nicked badly from misuse - everything from opening cans of finish to prying apart corroded metal machine parts.  For over a year, I slowly pieced together my own slow-speed wet grinding wheel, using a 14" Nova Scotia sandstone wheel.

But in the end, I found the fastest way to re-grind my blades was with my 6x48" belt sanders.  Using the Veritas angle jig, I simply ran each blade across the 80 grit belt (with the motor OFF) until it was evenly ground.  Then I followed with my other 3 belt sanders, which are set up with 120, 180, and 220 grit belts.  After the belts, I honed the blades further with Japanese water stones, at 800 and 4,000 grit.  This brought the blades to a fairly sharp state.

For further honing, I turn again to sand paper.     This time, it's Klingspor sheets, glued to a piece of glass.  I have 800, 1200, 1400, and 1500 grit sheets.

Somewhere in the high grits (I'm still experimenting), I switch the wheel on the bottom of my sharpening jig to an ellipse-shaped wheel, which allows me to concentrate pressure at the edges of the bevel.  Doing this rounds the ends of the blade slightly, which will allow me to smooth boards without leaving track marks from ever-so-out-of-square blade settings.

To all of those who prefer freehand sharpening: OK, you do you.  I don't sand my work anymore, and I don't chew through blades either. 

And don't forget to flatten the back of the blade too.  Need I mention do NOT grind a bevel into the back of the blade?  Read Hoadly's Understanding Wood for a primer on cutting.

If it sounds like a long and laborious process, it is. But now that my blades are shaped, I am careful with them, avoiding nicks, so getting them from pretty sharp to extremely sharp is no biggie.  Also, although I have used a Tormek and my own bigger, faster wet grinder, I still think sand paper is the fastest way to shape blades and even hone them.  For the 80-220 grit stage, you don't need much more than strips of sand paper on a piece of MDF, or even mounted to the belt sander itself.  For fine honing, something flatter than a belt sander platen is needed.

If you are using a plane for the first time, slide the sole of the plane around on a wide sheet of 15,000 grit sandpaper (on glass), and check for flatness. If the polish isn't even on the sole, you'll need to flatten it before you can continue.  Be careful and don't change the angle of the sole to the sides, or you'll have to account for that whenever you shoot with the plane.  Not the worst thing in the world, anyway, and to avoid this use the finest grit possible (to complete the job in less than three hours!), and a completely flat piece of glass or stone. 

Setting plane blades

As you can imagine, a plane only does a good job of flattening if the blade is square to the work.  I learned an easy way to prepare a plane for work from Ficnk's Making and Mastering Wooden Planes (Taunton Press).  Here's how to make sure the blade is square to the work:
  1. Clamp a board, roughly half the width of the plane blade, edge-up on the bench.  
  2. flip the plane belly-up, and bring the blade out until it is almost proud of the sole (but not quite)
  3. Run the plane the full length of the board's edge.  There should be no shaving.
  4. Bring the blade out a little bit, and repeat Step 3 until the plane takes a few fine nicks off the edge (these will be the machine marks from a rough dimensioning of the board)
  5. Take another shaving, until the plane is taking a thin, continuous shaving.  Now it's ready to set.
  6. Place the left side of the plane on the beginning of the edge, and take a shaving.  
  7. Do the same for the right side of the blade.  
  8. Observe the two shavings: the one from the left of the blade, and the one from the right.  Are they of the same quality?  Adjust the left/right tilt of the blade until both sides of the blade take the same shaving. 
  9. Now your plane is ready for business :)
My Planes

Before I leave you, I want to give a run-down of the planes I use in my shop.   The ones that get the most use are my E.C. Emmerich scrub plane, which is a special plane for the initial flattening of panels, my Stanley No. 4 1/2 smoother, and my Lie Nielsen jack plane.  I also used a nice big wooden jointer plane until recently.  All that's stopping me from putting it back into service is a trip through the grinding and honing process I described above.  I use these four planes a lot these days, mostly for flattening panels and final jointing of board edges for gluing up into panels. 

For routing, I do have a Stanley moving fillister plane, and a Record plow plane.  both of these planes need to have their blades re-ground and honed before I can get into using them.  For now, I rely on my router, mortiser, and chisels to make grooves...

...But I'm sure I'd be happier using the planes for those jobs!

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