plain saw

verb, noun — 2 senses

plain saw

verb

1

To cut into boards using parallel cuts that are tangential to the growth rings.

Note the difference in dimension due to the Figure 2 shrinkage of the semi-dry piece, also the difference in "cut" of the boards; the shrunken board being quarter sawn, while the adjacent boards are plain sawn.1921, Furniture Manufacturer and Artisan - Volume 83, Issue 22, page 178:
The problem with plain sawing is that the outer planks tend to warp.1999, Peter Oxenham, Integrated Science and Technology: Materials and Processes, →ISBN, page 36:

1 more example

The majority of softwoods and hardwoods, with the possible exception of oak, are plain sawn.2014, P. F. Lye, Woodwork Theory - Book 3, →ISBN, page 9:

plain saw

noun

1

A saw in which the blade has teeth with no pitch.

Either a dado head or plain saws may be used on the circular saw for this purpose.1930, Herman Hjorth, Principles of Woodworking, page 83:
There were two plain saws, a bow saw, a wood-chopper, two axes, three scythes, whetstones for sharpening scythes, files for sharpening the saws, tool kits, and a fairly good supply of nails.1974, Evgeniĭ Ryss, Search Behind the Lines, page 26:

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.