How To Cut Accurate Miters Easily Even on Non-Square Corners

RON HAZELTON:
Now you might think that most of the corners in a house would be right angles. That is pretty much perfect 90 degrees. But the fact is, old house or new, most of the corners are something other than that. And you know, what can happen if you try to cut a miter on two 45s for a corner that isn't 90? Well, you end up with something like this. Very nice.

Now this is my friend Mark Shapiro. He's invented a tool that takes the guesswork out of cutting miters on molding.
MARK SHAPIRO:
Correct.
RON HAZELTON:
How did you come up with this idea?
MARK SHAPIRO:
Well, I'll tell you, Ron, I was working on a job in Washington, DC, in Georgetown and it had an enormous number of unusual angles in it and I was doing all my calculations as I always do, with a T-bevel and a protractor. And each one of those calculations takes about a minute.

So in the hundreds of cuts in the course of a day, I thought it would be a great advantage to have a tool that would do it instantly.
RON HAZELTON:
So for a pro, it will, it will save time. What about for someone who's just getting started doing woodwork?
MARK SHAPIRO:
I think it would be even more important to have the tool because the math that's required is very confusing. On a miter saw, when you're cutting a 90 degree cut, the miter saw reads zero. On a protractor, it reads 90. So it's an unending source of confusion for people.
RON HAZELTON:
So Mark, show me how it works.
MARK SHAPIRO:
You simply take the two legs of the tool, place them against the work angle, and then in this case we're trying to get a miter joint. My reading is now 38 degrees on the miter cut arrow. So I simply set 38 degrees left, cut left, set 38 degrees right, cut right -- put the two pieces together and I have a perfect miter joint.
RON HAZELTON:
Mark's tool also works for inside angles.
MARK SHAPIRO:
Ron, that would be a 41 degree miter cut.

RON HAZELTON:
41 degrees. Well for me at least, it often takes a lot of trial and error to get a fit like this. Even when it comes to wide baseboards, it's just a matter of reading the gauge and setting the saw up for a bevel cut at the angle indicated. No need for guesswork here.

The tool can also be used for single angle cuts, like those on the end of a flooring plan. For this, the inside scale is read. So whether you're doing baseboard, chair rail, crown molding or even flooring, this seems to work pretty well.
MARK SHAPIRO:
It does indeed and this will work just equally well. This is the new mini model that will fit easily into restricted areas, or you can just fold it up and carry it around in your back pocket.

MARK SHAPIRO:
All right.
RON HAZELTON:
Did a nice job, Mark.
MARK SHAPIRO:
Well, thank you.

Cut Perfect Miters to Fit Irregular Corners and Angles with a Miter Gauge That Also Saves Time and Materials

Save time figuring for miter joints and prevent material waste resulting when a miter joint does not fit properly. Exchanging that T-bevel and protractor for the miter gauge demonstrated here will let you measure, calculate and convert angles to miter saw settings, and improve your productivity in a single step. All that is left is cutting the perfect miter.

Click Here for more information on the protractor used in this demonstration.

placing the legs of the miter gauge against the work angle

Step 1

Position the Tool against the Work and Read the Setting

Place the legs of the adjustable tool against the work angle and read the setting for the miter saw, as indicated by the red arrow. The angle is already converted to the correct setting--in this demo, 38 degrees.

Step 2

Adjust the Miter Saw to the Left and Right Settings

Adjust the miter saw left 38 degrees and cut one side of the miter joint. Readjust the miter saw right to 38 degrees and cut the other side of the joint.

fitting molding together in a perfect miter joint

Step 3

Position Pieces over the Work Angle in a Perfect Joint

Align the mitered end of the pieces of molding together on top of the corner or outside work angle. They join in a perfect miter joint as determined with the miter gauge.

positioning to measure an inside corner angle

Step 4

Place the Tool to Measure an Inside Angle

Open the tool so that it fits into an inside angle and place the legs flat against each wall. In this demonstration, the setting on the miter saw will be 41 degrees.

fitting together a perfectly-mitered crown-molding joint

Step 5

Adjust the Miter Saw and Cut the Molding

Set the miter saw to 41 degrees left and cut the first piece of crown molding in the demonstration, then readjust to 41 degrees right for the second piece. Join the pieces for the inside work angle.

measuring for a wide baseboard bevel cut

Step 6

Use the Tool to Measure for a Wide Baseboard Bevel

Prepare to cut a wide baseboard by measuring the work angle with the tool and then setting the miter saw for a bevel cut at the angle indicated.

Step 7

Measure for Single-angle Cuts for the Ends of Flooring Planks

Use the tool to measure in corners for single angle cuts like those on the ends of flooring planks. For that purpose, read the setting on the inside scale on the miter gauge.

examining the mini-model of the miter gauge

Step 8

Use the Full-size or Mini-model of the Miter Gauge

Choose either the full-size or mini-version of this miter gauge. The smaller version works identically to the first, but is small enough to fit in a back pocket or a tool belt.