Sawing Lumber

Cutting Lumber
One of the things I had to improve on when I started woodworking, was cutting lumber to an exact dimension, either length or width.   I use a miter saw (or chop saw) to size all the lumber pieces in a project.   I use the same wide tape measure and a .5mm pencil to mark where to cut.   Then I carefully align the saw before the cut.   I use a table saw for ripping to width.   I also use a bandsaw for resawing.

But before I did this I had to be exactly sure where my saw is cutting so I did a little experiment   I made two marks exactly 1/32" apart on a piece of scrap lumber.   I cut the board with the saw blade exactly in the center of the right hand mark.   Then I measured from the edge of the cut to to the remaining mark.   The distance should be the 1/32" between the original two marks.   You might even see part of the original mark on the edge of the cut, but that doesn't happen much, most saw blades have a little flutter, remember that mark was .5mm thich so your expectig you saw to have less than .25mm (less than .010" flutter).  

Note: when you use a miter saw, the fence is perpendicular to the blade so this makes square corners.  
When you use a table saw, the fence is parallel to the blade so the piece you cut will have parallel sides.   To make square corner cuts with a table saw, you must use a miter square with a miter bar or a cross cut sled.   If you make your table saw's crosscut sled take a look at Matthias Wandel's table saw sled video to be sure your sled is square.  

If you notice tiny splinters sticking out at the bottom of your cut when cutting soft wood, your blade is probably dull or needs cleaning.    

You should periodically check your saw for square with the fence and for exact vertical using an engineering square not a try square it isn't as accurate as you need.   Your saw's manual should say how.  
NOTE:
Whatever square you use to set up your tools, sets the accuracy for all your projects.  

Jointer Squaring
If you use you jointer as much as I do, you'll want to be sure it's fence is square with the bed.   The jointer's manual should explain how, and again, use an engineering square.  

Bandsaw Squaring
You bandsaw blade needs to be square with the bed, especially if you resaw.   If you resaw, you'll also want to see my resaw guide page and my Drawer Construction page.  

Cutting Lumber: Mark the exact length with a .5mm pencil.

Cutting Lumber: line up the edge of the saw blade's teeth with the center of the .5mm mark (red circle).   Where a saw cuts depends on how much flutter the blade has: Make two marks evenly spaced, Cut on the right hand mark then measure the space between the cut and the remaining mark to see exactly where the saw cuts.   You might need a better or sharper saw blade.

Cutting Lumber: Closer look at edge of saw blade and .5mm mark.

Cutting Lumber: If you look closely, in the red circle, you can see a little bit of the mark after the cut.   You may not be able to cut quite this accurately, since a lot of saw blades wobble when they are turning.   Also, if your saw blade has alternating set, you use a tooth with set to the left (in this case).