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.