What are the parts of a low-angle
There are low-angle, bevel-up versions of each type of bench plane – jack, fore, jointer and smoothing planes.
A low-angle bench plane shares some of the features of bench planes based on the Stanley / Bailey design, but there are also significant differences, several of which make it more attractive to some woodworkers.
The low-angle plane has a lower centre of balance than the Stanley / Bailey type plane. Some claim this makes it easier to hold the plane level when planing narrower edges.
This type of plane does not have a chip breaker. Because the bevel is up, its angle would prevent the shaving, or chip, reaching a chip breaker a little higher up the iron.
In effect, the iron's bevel itself acts as the chip breaker in a bevel-up plane.
The body of a low-angle bench plane is lower than the more traditional Stanley / Bailey type, due to the much lower bedding angle of the iron (the angle at which it sits in the plane).
It is this feature that gives the low-angle plane a different feel, and makes it easier to keep level laterally (horizontally across the plane's width) when planing narrower edges of wood.
The sole of a low-angle bench plane has an adjustable mouth plate (see below), which a standard Stanley / Bailey-type plane does not have.
In a low-angle plane, the mouth itself is adjustable, rather than the moveable frog of the Stanley / Bailey design closing or opening the gap between the iron and the leading edge of the mouth.
Adjustable mouth plate
This plate – a section of the front part of the plane's sole, or the toe – can be moved backwards and forwards to open and close the mouth opening. You need a bigger opening for thicker shavings and a smaller opening for thinner ones, so the mouth opening is closely related to the iron's depth setting.
Turning the front knob anti-clockwise enables the plate to be moved backwards and forwards by pressure on the knob. Turning the knob clockwise secures the plate in the desired position.
Mouth adjustment lever
On some low-angle planes, there is a lever positioned under the knob which is turned to move the adjustable plate backwards and forwards once the knob has been released. The knob is re-tightened to secure the plate.
Another feature of some low-angle planes is the mouth adjustment screw, or screw stop. This is set so that it stops backwards movement of the mouth plate at a set position, making it quick to get back to the normally preferred position after the mouth has been opened for deeper cuts.
The frog area of a low-angle plane is fixed – cast as one piece with the body, so that it cannot be removed, and gives greater strength to the plane's construction.
The bed – the sloping upper surface of the frog on which the iron sits – is usually angled at 12 degrees. It is "machined" – milled on a precision grinding machine after casting – to ensure the top surface is perfectly flat for the bedding of the blade.
Blade depth and lateral adjuster
A low-angle plane normally has a "Norris-style" adjuster for the iron. This single device adjusts both the iron's depth and its lateral angle – the cutting edge's horizontal position across the width of the sole. The cutting edge should be parallel across the sole.
This is how a Norris-style adjuster looks with the iron removed.
The thumbwheel of the adjuster is turned clockwise to advance the iron through the mouth, and anti-clockwise to retract it.
Moving (but not turning) the thumbwheel to the right or left adjusts the lateral position of the iron.
Seefor more information about this adjuster, which is also used on some standard bench planes.
Some woodworkers like to be able to adjust the iron's depth while actually planing, and say the Norris-style adjuster's low position makes it difficult or impossible to do this.
At least one version of the low-angle plane solves this problem with an "overhead" blade adjustment wheel that can easily be reached by the forefinger during planing
Lever cap, screw and thumbscrew
The low-angle plane's lever cap has a thumbscrew instead of the cam lever of the Stanley/Bailey design. Turning the thumbscrew clockwise levers the lever cap against the lever cap screw and the iron, holding it firmly in place.
A major difference is that the iron is bedded at a low angle – usually 12 degrees – and bevel up.
In bevel-down planes, the cutting angle is governed solely by the angle at which the iron is bedded.
The low-angle plane's blade is usually honed with a bevel of 25 degrees which, added to the 12-degree bedding angle, gives an overall cutting angle of 37 degrees.
By contrast, a standard bevel-down Stanley/Bailey bench plane has a frog angle of 45 degrees, which creates a cutting angle of 45 degrees (since the bevel angle is not a factor in this calculation). Seeand for more about this.
The true versatility of a low-angle plane is realised when it is used with irons that offer different bevel angles.
The tote, or rear handle, is a pistol grip design which is similar to the more common Stanley / Bailey-style bench plane.
The front knob is similar to that of the Stanley / Bailey style bench planes, except that it also releases and secures the mouth plate adjustment lever as described above.