What is a block plane?

13th August 2021


	What is a block plane?


	Shop for Woodworking Hand Planes


			What it’s used for
			A block plane – either metal or wooden – is quite a versatile tool. You can use it for:

			Trimming and smoothing end grain This is the block plane’s primary purpose. The plane is sometimes used in conjunction with a bench hook or shooting board – workbench accessories for holding wood while working on it – when planing end grain.

			Erasing mill marks on wood Machine-milling marks are sometimes left on timber. These can be removed with a few passes of the plane.

			“Squaring up” small stock You can use a block plane to “true” very small pieces of wood. Clamp the plane upside down in your vice and you can plane the smallest of pieces by running them across the cutting edge.

			Chamfering an edge Draw guidelines as and plane the edge at 45° to create perfect chamfers, or bevels.

			Fitting doors and other parts If a door is binding (rubbing against another part when it is opened and closed) there’s often no need to take it off to make it fit. Instead, just mark the high spot and shave it off in situ with your block plane.

			Trimming a proud dovetail or mortise and tenon joint The word “proud” here refers not to a joint that feels superior in some way, but to parts of the joint sticking out slightly after assembly. This is not a mistake, but a means of ensuring the parts fit perfectly after the block plane has been run over them.

			Characteristics
			One-handed use Most of the metal versions and some of the wooden ones are small enough to be used with one hand.

			Iron at lower angle than standard planes A block plane is a small hand plane which typically has its iron, or blade, bedded at a lower angle than the standard bench plane.

			Metal block planes often have their irons bedded bevel up, at an angle of around 20 degrees to the sole, or bottom, of the plane. There are also low-angle versions, with irons bedded at just 12 degrees, again bevel up.

			Apart from the materials used to make them, there’s a fundamental difference between metal and wooden block planes.

			Even the hardest wood is not strong enough to support low-angle, bevel-up irons. Due to the stress placed on the the iron’s “bed” when the plane is being used (caused by the resistance of the workpiece to the movement of the cutting edge through its surface), the shallow, bottom end of the bed (the rear edge of the mouth) is likely to give way.

			This is why so many wooden planes have their irons bedded bevel-down, with a pitch of between 35 and 40 degrees. The higher angle gives greater strength to the wooden bed, while the bevel-down iron means the bevel does not increase the cutting angle.

			A metal, bevel-up block plane with its iron pitched at 12 degrees usually has a bevel on its cutting edge of around 25 degrees, giving an overall cutting angle of around 37°. This is 8 degrees more acute than the standard bench plane which has a bevel down iron pitched at 45 degrees, giving a cutting angle of 45 degrees since a downward-facing bevel does not affect the cutting angle.

			A wooden block plane’s iron, bedded bevel down at an angle of 35 degrees, again gives a more acute cutting angle – 10 degrees lower than the standard bench plane’s cutting angle of 45 degrees.

			This lower cutting angle which is a feature of many block planes, both metal and wooden, is what makes them more suitable for cutting end grain. The lower cutting angle is better for shearing across grain, with more of a slicing action than the standard 45-degree iron.

			Too short for straightening Because they are usually ‘pocket size’, most block planes are too short to be used to straighten wood. The short sole would simply follow any undulations instead of shaving off the high points and bridging the low points until the board was level, as a long plane would.

			Metal block planes are usually 127mm (5″) to 178mm (7″) long and have irons between 38mm (1½”) and 44mm (1¾”) wide, with bodies a little wider than the irons.

			However, there are also miniature metal block planes as little as 60mm (2½”) long and 19mm (¾”) wide, with an iron just 12.7mm (½”) wide. They are useful for small-scale work, or where a bigger plane would be difficult to use due to space restrictions.

			Wooden block planes also vary in size, the average being around 175mm (7″) long x 54mm (2 1/8″) wide.

			How it got its name The block plane was first manufactured to meet the demand for a plane which could be easily held in one hand while planing across the grain, particularly the ends of wooden boards. This work is called ‘blocking in’ by some carpenters, hence the name block plane.

			There are also claims that the block plane gets its name from one of its traditional uses – levelling and removing cleaver marks from butchers’ blocks that were built with the end grain facing up.

			Number
			Metal versions of the block plane made by Stanley were allocated Stanley model numbers which are still often used today when cataloguing, advertising and ordering planes.There were so many variations on this versatile plane that the list is very long, but to summarise they are numbers 9 to 9 3/4; 15 to 19; 25; 61 to 65½; 100 to 103; 110; 118; 120; 130; 140; 201 to 205; and 220. They vary in size, types of lever cap, types of adjuster and whether or not they have adjusters.