My favorite square isn't

[Bob Glenn]

After a lot of years, I just discovered my favorite try square isn't square. :eek: It's a six inch Crown, the kind with three brass rivets joining the metal blade to brass faced wood leg.

I know you can square a metal framing square by careful peening on the angle, however, does anyone know how to tweek the above mentioned square? It isn't very far off, but just enough to cause me to question when and where to use it.

[Zach England]

I have one of those little crown squares and mine is proud about 1/4 degree...I just put it in the drawer and never used it again, but if there is a way to correct it I too would love to know. I have thought about mounting it in a jig of some sort and rubbing the metal on some sandpaper or a stone...seems like more work than it is worth.

[Bruce Haugen]

I have two experiences truing squares. The first was a Freud try square constructed like yours, bought back before I knew anything. It was out of square in most ways, so I felt no qualms about taking a file to it and making it right. I didn't know of any other way to adjust it.

The second was a framing square that was out of square about 1/32" in 16". There is an old tip floating around about taking a ball peen hammer to either the inside or outside of the angle of the square to stretch the metal and true it up. I did that, and now it is square enough that when I scribe a line with an Xacto knife, I can flip the square end for end and there is no difference.

[Robert Rozaieski]

You can file the blade square if you know how to check it. Use a straight board to check it and use the file to adjust the blade angle until it is square. Here's a video I did on layout tools that discusses how to check them and how to fix them (I used a wooden try square in the video but a metal balded try square can be checked and adjusted the same way).

http://logancabinetshoppe.weebly.com/1/post/2009/06/episode-3-layout-tools.html

[Jim Koepke]

I have squared mine up with a file and some care. Go slow, metal comes of too easy sometimes.

Be sure to check inside and outside.

jim

[Bob Barkto]

The easiest and safest way I have found is to whack it.
Seriously.
Filing is irreversible and very difficult, especially on the inside edge of the blade.
Stanley adjusted their riveted squares this way. Others probably did as well.

Hold the stock in hand with the blade pointing away and with mostly wrist action sharply rap the end of the blade on a stout piece of wood. An end grain block of 4x4 hardwood is good.

This image shows how to open the angle. Hit the outer edge to close the angle.
One good rap will move a few thousandths.
133729

http://imagefra.me/view.php?img=3/1/1/bobbarkto/f_squareadjusm_9667175.jpg&srv=img34

[george wilson]

With a riveted blade,I wonder if the blade being whacked would loosen the rivets' grip on the blade?

For all steel,cheap machinist's squares,I do adjust them by bending,but they aren't made the same way.

The blue steel blades in the woodworker's squares are made of the same steel as saw blades,and would file IF you have the skill to do it properly.

[Bob Glenn]

Thanks to all for your suggestions. George, I think you're right. I am concerned that wacking the blade into square would be a temporary fix, which may return to the original position sooner or later.

I should probably just junk the square and buy a better square.

[Bob Barkto]

I've only done a handfull, maybe 5 or 6, but in my experience the fix is permanent.
Never had one loosen or revert.
Not much force is used. A quick snap of the wrist is all. Better to make a few light hits than one heavy thump I think!

As I mentioned this technique is (was) done at the factory by at least one manufacturer. At the time Stanley used this technique their tools were still respectable and held up in use. (they may still, do they even make riveted wood squares anymore?)

I'd also consider that riveted squares with wood stocks are not what I would consider precision instruments. The wood will move a bit with changes in atmospheric conditions which will move the blade some, so how much precision can we expect from such a tool?

As you said, filing takes quite a bit of developed skill. Filing the blade and keeping the two edges perfectly parallel and straight and at 90 to the stock is not trivial.
When filing the inside edge you can't get much of a stroke with the stock in the way. It's almost a given that most would end up with a taper towards the end of the blade and/or a "step" right at the corner.

Whacking the square can be done by most anyone as long as they have an accurate reference to check their work.



With a riveted blade,I wonder if the blade being whacked would loosen the rivets' grip on the blade?

For all steel,cheap machinist's squares,I do adjust them by bending,but they aren't made the same way.

The blue steel blades in the woodworker's squares are made of the same steel as saw blades,and would file IF you have the skill to do it properly.

[John Coloccia]

Many metal machinist squares are pinned also. They're just ground flat afterwards so it's hardly noticeable but if you look very carefully, you can sometimes make out a couple of faint, round marks indicative of pinning.

Personally, when I have a square that's out of square, I toss it in the trash. I don't use my "good" squares for anything other than checking each other out, checking out my cheap squares, or sometimes machine setup. I have a cheap set of everyday squares that get used for everyday stuff, and when I drop one enough times that it's finally not true anymore, I toss it and buy another one. They're cheap enough that I don't cry ($10 to $15 bucks each, depending on the size...less than a cheap band saw blade). That said, I've maybe tossed 2 or 3 IN MY LIFE because of this, so it's not like someone's getting rich selling clumsy John new squares :) Those suckers are durable during normal use and long as you don't knock them off your bench all the time. I've been using the Groz squares and have been very satisfied.

If you're going to bang on it with a hammer or file it, my one word of warning is to be sure that both the inside and outside surface are exactly 90 degrees to the base and dead nuts parallel with each other. I can't tell you how many squares I've seen over the years that are 90 degrees on the outside surface, and something different on the inside. This will drive you to drink when you lay something out 20 times and STILL can't get all the lines to come out right! This is especially true with wooden squares. Come to think of it, I don't think I've ever seen a wooden square that's true on the outside AND inside edges. Machine setup? Nuh uh....

[george wilson]

Yes,but at least the pins in machinist squares are steel,not brass,which I was concerned about the steel blade biting a little notch into when adjusting.