Jack Plane Description and its Purpose

A jack plane is defined as a general-purpose woodworking bench plane. It is used for dressing timber down to the required size. The jack plane is generally known as the first plane for cutting the rough stock. Where the scrub plane leaves off, the jack plane takes over from there and is being used for shaving off smaller amounts of wood to reduce the thickness to make it to the desired size. The jack planes are usually longer than the smoothing planes. Therefore, it has a higher capability to straight the edge than a smoothing plane. In practice, the jack plane is used immediately after the scrub plane and before the fore plane, jointer plane, and smoothing plane.

How it got its name

Jack plane got its name from the saying "jack of all trades," as jack planes are made to perform the work of smoothing, fore, and jointer planes, mainly on smaller pieces of work.

Critical Characteristics of jack planes

The angle of the iron

There are standard and low angle metal versions of the jack planes available in the market. In terms of the irons pitched the standard version with 45 degrees slope down, and the low angle metal version with 12 degrees bevel up. However, the wooden jack planes do have the irons pitched at 45 degrees.

The size of the jack plane

Jack planes usually have a capacity of 292mm/ 11½" and 380mm/ 15" length. On the other hand, the width of the plane's iron is just 10mm/ 3/8″ or narrower than the plane's body can be 44.5mm, 50mm or 60mm wide.

The shape of the cutting edge

The jack planes are treated as multi-purpose planes. Therefore, it's iron's cutting edge is honed straight and with rounded corners. It makes the plane suitable in addition to doing the jointing and smoothing the work. The rounded corners are designed to serve to prevent "tracks" being left on surfaces that are wider than the iron.

Design number

The metal versions of the jack plane produced by Stanley. However, these metal versions were given to Stanley model numbers, which are still used today in terms of cataloging, advertising, and ordering planes. However, some different numbers and sizes are available for purchasing. Jack planes made to the Stanley/Bailey design are the No. 5, No. 5¼ and No. 5½. Number 5¼ is smaller than the number 5, and the number 5½ is bigger.

Conclusion

A jack plane is essential in the woodworking projects. However, its primary purpose is smoothing the edge, sizing of timber, but just for making it smaller to the expected size. At the end of the nineteenth century, it came to be referred to as a "No. 5" plane or a "Bailey pattern No. 5". The "No." was developed by the Stanley Tools to label its Bailey pattern plane products to identify products. Other manufacturers in that era didn't have the same number scheme for their planes. However, Millers Fall and Sargent both used different numbers to refer to the same planes.