
The real world doesn’t always involve easy-to-reach right angles That’s why you need a tool like the Empire protractor and angle finder in your toolbox.
This 6″ long tool has a short 3-1/2″ side which allows you to get it into tight places a T-bevel or other measuring tools won’t fit. It’s made from yellow polycast plastic with brass hardware.
You can use the tool for measuring inside and outside angles, laying out miter angles, and transferring angles.
Advertisement
This little problem-solver isn’t very expensive – you can pick it up in person at most Home Depot Stores for $6.
Price: $6
Buy Now (via Home Depot)

General Tools also offers a very similar angle finder. It looks to be identical to the Empire model, except it looks to be a darker shade of yellow and it has slightly different markings. It also appears to have a vernier scale for reading minutes of angle.
Price: ~$5
Buy Now (via Amazon)
Advertisement
How I’ve Used it
The protractor and angle finder isn’t a tool I use every day, but it’s indispensable when it’s the only tool that works. Below are some of the uses I’ve found for the tool. Note that some of the photos are recreations, since I didn’t have the forethought to actually take photographs at the time.

Our bedroom door makes an odd angle with the hallway and I originally picked up this tool because a T-bevel or protractor wouldn’t fit.

When I was building my sheet goods storage cart, I used the tool to ensure that the angle of the rear posts was the same on both sides.

The inside angle is useful for determining the angle of small objects. Here I’m measuring the angle of a Milwaukee bit holder in order to create a 3D model of it.

The angle finder can be used like a normal protractor. Above, I’m using it to verify that an angle I cut on a miter saw was 60°.

Finally, here I’m using the inside angle to check that this dovetail key was 12°. It took a lot of grinding to get the angle right. Of course the problem with a plastic tool is that you have to let the metal cool before you use it.
Allen
At first glance it looks handy to have. I’m wondering about all the joints it has in order to work; each one would introduce error I would think.
Nathan
probably very little. say 20 seconds or .2degree and that’s if they were sloppy after years of wear.
For wood cutting – and most plastics probably plenty of accuracy. For detail metal work like into the 0.001″ then yes it would be a bit wonky. In that world you’d use a different tool anyway.
Steve
I think you mean 20 minutes & that would be 1/3 °, or .333°
20 seconds = .0055555°
Degrees (°) minutes (‘) seconds (”)
1° = 60′
1’ = 60”
fred
I bought a General one years ago. Like you, I thought it would be useful to replace a sliding bevel that has no calibrations. I found it to be sloppy and inaccurate. It was off by about 1 to 2 degrees compared to a known accurate protractor. It’s thin plastic deflected if you pressed a pencil too hard along its edge. Maybe I had a bad one or one with rivets that were pressed into the plastic poorly. I gave it to my wife for crafts. I don’t recall seeing her using it. I hope the Empire one is made of better stuff and more accurate. I still does have the advantage of being cheap and small – compared to even a low-priced bevel:
https://www.homedepot.com/p/Empire-True-Blue-Heavy-Duty-Aluminum-T-Bevel-132/202035310
Anson
I also have the “General” brand version. Looks identically to this. On mine the two rivets on the bottom are loose ~1/16″.
Mine went into the trash today after I realized it would never see use.
Benjamen
Interesting that both you and fred said the General Tools version was loose/sloppy.
I thought it was identical to the Empire, but I may be wrong. The Empire I have is much stiffer.
The scale isn’t perfect, it might be parallax, but the indicator seems like it’s just off the center of the mark when square, but that’s maybe 10 minutes not 1 or 2 degrees.
Hilton
I bought one that must have been sourced through either Lee Valley or Peach Tree. I haven’t used it in ten years but it still could be handy one day.
Jared
I’m going to try one of these to help me with my baseboards. I’m getting pretty good at the corners as I work my way through the whole house anyway, but this is cheap enough that it only has to help a little bit to be very worthwhile. Thanks for posting.
Kevin
After seeing this, I picked one up yesterday thinking it would be useful, but the one I got was off by about a degree. I like the design, so it’s too bad the execution is apparently not consistently accurate. (One thing your pictures don’t show is how you can collapse the square so that the long arm is parallel to the indicator arm, which is useful for measuring outside angles on large objects.)
Anyone know of a metal version that doesn’t cost way more?
Benjamen
That’s too bad. I’d bring it back and say it’s not measuring correctly — either get your money back or try another one.
I just tried a few right angles. I read just shy of perfectly lining up, but nowhere close to even being between degree markers. I’m not sure why your protractor would be so far off, I’m not sure if there’s manufacturing variability, deflection in the material, or what.
Yeah I discovered the “collapse” feature right after I wrote the post. I actually thought about inserting another image, but decided against it.
Pantaz
Quite a few variations of the bevel protractor out there in a range of accuracy and usefulness. The all-metal ones — even the cheap ones — tend to offer better utility for me, simply from the added stiffness, compared to plastic.
Paul Zadworniak
Look, to do any accurate work these plastic “protractors” are NOT the thing to use. I had one and when it came time to do precise work it was way off (even when tightened hard there was alot of play in all the linkages). The rivets are not closely toleranced PLUS it’s plastic (bendy and flexy, an additional error). Look elsewhere if you are doing precise work. End of story. And , no, it wasn’t a defective item…it’s just the nature of plastic and cheap tools that are made with large tolerancing (that’s why it’s cheap). Just being honest.