Adjustable Mouth on LA Block Plane

[Buddy Forshee]

I am thinking about buying my first plane. I know nothing about planes. Please tell the me the purpose of the adjustable mouth on planes. Thanks in advance. I appreciate your help!

[Gary Bingham]

I am thinking about buying my first plane. I know nothing about planes. Please tell the me the purpose of the adjustable mouth on planes. Thanks in advance. I appreciate your help!

With an adjustable mouth, you can either make the opening between the blade and the front of the mount smaller, allowing finer shavings and a smoother surface. Or you can open it up a little more, allowing for thicker shavings with the possibility of tear out.

Here's (http://www.valuelinx.net/~gbingha/pics/shaving_example.jpg) a pic from garrett hack's handplane book. Sorry for the bad pic, I can't find my scanner cable.

By the way, the pic shows a bench plane, but the principle's the same.

[Alan Turner]

I have the LN 60 1/2 LA, adjustable mouth block plane, and change the mouth opening with some frequency, depending upon the task at hand. Since you are venturing into the plane world, might as well start out right and acquire one with an adjustable mouth. The mouth opening is a critical feature of the way a plane works. When you are forced to go against the grain, it is especially important as the tight mouth breaks the grain just in front of the iron and prevents a split (tear out) from running. It makes a very real difference.

[Ed Falis]

I'll second Alan's recommendation of getting an adjustable mouth block plane. It's a great tool that you'll find natural to start using in all kinds of situations. Try either the Lie-Nielson or the Veritas from Lee Valley (I have the latter and it's very nice). Veritas also has a LA smoother with an adjustable mouth that is nice, though having had it awhile, I think I'd have gotten their 4-1/2 first if I were to do it again.

- Ed