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By Rob Rohde-Szudy - Madison, Wisconsin - USA



Edge Tool Envy - Part 3 - Block Plane

To Part One

To Part Two

Last time we looked at getting a sharp edge. Now let’s look at reviving a dead block plane.

We all have one of these things kicking around the shop somewhere. It’s probably rusting in a corner. That way we don’t look at it so often and feel bad that we haven’t a clue how to make the thing work. If you don’t have one, they are often sold cheaply at farm auctions unless some antique knick-knack seekers decide they look pretty. I’d never pay more than $5 unless I was certain it was a real gem.

We’re starting with a block plane because most are pretty simple. They put the bevel up and don’t bother with a chip breaker or cap iron. Block planes aren’t meant for long strokes on long grain, so these parts aren’t needed. Block planes are meant for end grain – for making a butcher block. Hence the name. Nonetheless, they see plenty of use doing jobs better suited to larger planes because they are lighter, smaller, handier and easier to get working. I freely admit that I often use a block plane where a bench plane would be better suited, since the block plane is easier to use with one hand, more likely to be sharp because it’s easier to sharpen. And they’re so small and cheap you can have a few of them and never lack for a sharp one.

First have a look at how the thing works. Usually the only adjustment is a lever that extends and retracts the blade. Occasionally there is a side-to-side adjustment as well and really classy ones allow you to move the frog back and forth to vary the mouth size. Usually this last adjustment is reserved for larger planes. In fact our example plane has no adjustments at all. To change the blade’s position, one loosens the hand screw a bit and wiggles the blade into the desired position. Here are two different planes taken apart.

Don’t dive in on the blade first. Sharpening the blade does little good if the sole isn’t flat. And usually they’re not flat, since the metal in front of the blade gets worn down. Retract the blade and set it on the glass you use for sharpening. The sole should lay perfectly flat on the glass. If it rocks a lot, the sole might be too warped to grind true. If it rocks only slightly or not at all, it’s probably OK.

The next step is disassembly and cleaning. Be sure you can remember how it goes back together, then clean all parts thoroughly with mineral spirits and an old toothbrush. Brake cleaner spray is wonderful stuff on stubborn pitch. Remove rust with #000 steel wool. Look for cracks in the casting. Cracks are especially common near the mouth. Unfortunately, these often mean the plane’s frame will flex in use and make it difficult to use. If you find a crack, save the effort and find another neglected plane to work on. But save the iron and other parts, since they might fit another plane you find later.

Now let’s true the sole. Set up your glass with #100 wet/dry sandpaper or coarse emery paper, and reassemble the plane with the blade retracted. Don’t try to do this with the plane disassembled because the frame flexes a little when the blade is tensioned. If you lap the sole with the blade out, it probably won’t be true when you put it back under tension.

Sole lapping

Truing the sole is as simple and monotonous as it looks. It’s a large area of metal to remove. There’s no problem doing this while watching TV and you’ll need lots of coarse abrasive. Planes are hard steel and they dull the abrasive fast. Keep grinding until the entire sole is covered with scratches. I grind the first pass sideways so I can distinguish these new scratches from the longitudinal scratches the plane acquired in use. When the bottom is evenly marked with crosswise scratches, you’re ready to move on. Just like with the blade, continue through the smaller and smaller grits, testing with crosswise scratches and a magnifier to determine when each step is done. By the time you’re done with the crocus cloth, the sole should be a dead-flat mirror finish.

On this one I was in a hurry and stopped at #240, which is not ideal but still a dramatic improvement. The plane is nicer to use if you go all the way to a mirror-like finish, however. A smooth finish will slide easily over the work, which is ideal. If you plan to use a plane with a shooting board, you should also lap the sides, taking care that they are square to the sole. I made a few passes on this one just to ensure the sides were in the right ballpark. I’ll go further if this plane winds up seeing service with a shooting board.

Now we’ll tend to the blade. This is just like the work we did with the chisel, but with a couple refinements. First, be sure to keep the edge square. I think it’s best to grind the blade completely square first, grinding as if you were trying to dull it. Then you don’t need to worry so much about squareness while sharpening.

The other refinement is how we hold the blade. We hold it like the chisel, and in fact that is why I used plane iron photos when discussing the chisel. This isn’t quite as quick and fun as sharpening that little chisel. The hands start to cramp. So maybe we should look at options for honing guides.

Honing Guides

The Veritas honing guide cost me about $25 when I got it and works quite well. I think they’re up to about $40 now.

Veritas

There are cheaper ways, though. Bench plane irons have a mounting slot that allows this cheap trick. (By the way, I’m using “blade” and “iron” interchangeably.) A regular carriage bolt and some nuts and washers adjusted to the right length does fine. You do have to be more careful about keeping things square. It also doesn’t work without a hole in the blade.

Since I got the paper wheel system, I usually don't even bother with a guide except for grinding the relief angle.

In use

From using the chisel, you now know about cutting in the right direction with respect to the grain. You also know to take light cuts so the blade doesn’t bog down. Both of these get more important now, since a plane offers no latitude for varying the cutting angle.

If you get chatter or grain tear-out when you’re taking the lightest cut possible, there are a few things to try.
• Reverse direction of cut
• Apply more downward pressure – front, rear or overall
• Test your blade for sharpness

On really tricky grain you might need the more-complicated planes that have chip breakers. But boats like straight grain, so the only time we run into this is when laminating rather bad wood. If you are not equipped with bench planes, you might have to resort to a sanding block.

I use block planes in what many would consider to be the “wrong” way.

Chine planing

Let’s face it, a lot of boat parts wouldn’t clamp conveniently to a cabinetmaker’s bench even if I had one. So the vice often ends up being a knee or a butt. I only found out later that this is the accepted practicing among Japanese woodworkers. For me it was simple necessity. It’s not easy on the joints, but it will have to work until I get around to making some benches better-adapted to boat work.

Bench planes

So what about bench planes? The only real difference is the chip breaker. The bevel is flipped down rather than up, and this extra piece of metal is screwed to the blade to make the shaving you're cutting – the chip – peel up and away from the blade.

Cap iron

Obviously this needs to meet the blade exactly, or the chip will find its way under the chip breaker and foul up the works. Making this joint tight is the biggest pain in the butt of tuning a bench plane, and the biggest reason I use block planes so much. Here's one where I polished both up well enough to work, if not flawlessly.

Cap iron

There's another thing. Both the chip breaker and blade edges need to be at exactly 90 degree angles from the centerline or you get this:

Chip breaker

Again, this is just one more thing between me and getting the task at hand done. For gnarly grain in furniture you really do need the chip breaking action to avoid tearout, but for the straight grain we need for instant boatbuilding, it's usually more trouble than it's worth in my opinion. I do, however, keep a long jointer plane sharp for the times when I need a truly straight edge.

Jointer

Rather, I've become sort of a connoisseur of anything without a chip breaker. One of my favorites is an inexpensive Indian-made low angle block plane.

Low angle

This one actually has an adjustable mouth, which is almost as good as a chip breaker sometimes. It's hard to see in the photo, but the front part can change distance from the blade, opening or closing the mouth.

Low angle

Another non-chip breaker tool I use quite a lot is a Veritas low-angle spokeshave. I just checked the price and they are up to $65. I use it so much, however, I think I might even pay that in today's money.

Anyway, by the time you have it down with the block planes and their relatives, you’ll know more than enough to seek out sources on bench planes who know way more than I do. Until then you know plenty to start planing off your saw marks.

Until then make sure to keep your shavings. Good tinder!


Rob Rohde-Szudy
Madison, Wisconsin, USA
[email protected]

*****

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