Thread: Newbie - using tri-square

The edges of the blade in a tri-square should be parallel so you are ok to use either edge.
You can still check the inside edge by scribing a line and flipping it over. It just checks if it is 90° to the fence.

Thanks for your post. It reminded me I had Jim Tolpins new traditional woodworker where he explains the process.
He advises that once joined to the handle or headstock both sides of the blade or tongue should be tested for square. If not plane the appropriate side. The reason for doing the "inside" is so you can use the square for checking the edge or corner of a board.
Planeing the outside is one straight stroke whereas you will need to take a different approach on the inside.
I would make a couple or at least a prototype so I could have a practice go , but I tend to bugger it up at least once during a build

Just for the record, folks, it's actually a trysquare (i.e. for 'trying' squareness). Sorry, the pedant in me just pops out...

Otherwise, what NC sez. As long as both the blade of the square, and the stock, are parallel-sided, it doesn't mater which pair of edges (inside or outside) is square, the other must be - simple Euclidean geometry! And yes, if you planed the outside of a wooden square blade to bring it into line, you would have to do the same to the inside to keep it square, unless it was already square, which means either the stock or blade was not parallel.

If I were building a wooden square, I would go to some trouble to ensure both stock & blade were as true as I could get them before assembly, but during assembly, I would be concentrating like heck on getting the inside edges absolutely dead-on 90 degrees. If, after the glue has cured, the outside is off by a fraction due to wood expansion or malign fate, you might be able to touch it up & have a square that works inside & outside, as it should.

Squares have a rather unfortunate habit of getting out of whack, for all sorts of reasons. It doesn't matter if they are all-wood, wood & metal, or all metal, at some point in their lives, nasty things can happen, or sufficient wear & tear will eventually do it. (I was told in no uncertain terms by Chris Vesper that his squares are an exception & will never get out of true...). However, even if you own a Vesper, it's a good idea to check your working squares on a reasonably regular basis, either against a treasured & highly-protected 'reference' square, as some do, or by the 'scribe & flip method', which if done properly, is just as accurate as holding two squares together (in fact you have to hold them very carefully, I've found, or you can easily get a wrong reading). I'm a great fan of the Clenton 'recalibratable' squares. In fact, in the spirit of sincere flattery, I made a couple of my own. The fussiest part is drilling out the stock for the slugs and barrel nuts, the rest is just painstaking work getting the two bits straight and parallel. If I valued my time at $10 an hour, they only cost about 4 times what Colen's sell for......

Cheers,

Here's an idea on clamping it square http://www.popularwoodworking.com/wo...-so-its-square

Thanks All,

Yeah i realised a little later that the inside would need to be square if you are checking the edge of a board for square.

I suppose i just keep testing the squares and if it goes out make a new one (as i don't like my chances of trying to plane both edges to keep perfectly parallel).

That and start saving for a Chris Vesper square.


Cheers!

Originally Posted by marphlix

....That and start saving for a Chris Vesper square.....

I can almost guarantee that you will end up with more than one square, and out of the ones you have one will be your favorite.

When working in the back blocks of Viet Nam, I saw lots of village carpenters using wooden try-squares. They are not hard to make, and as you say, if it wears or goes out of whack, just make a new one.

The major problem with a wooden blade, for me, is that it is a bit too easy to take a shaving off when using a striking knife. You won't cut into the blade if you concentrate & hold the knife just so, but a moment's inattention, or some unexpected odd grain, & sffftt, off comes a fine shaving before you can stop. A few of these and your blade starts to look a bit daggy. I had an occasional accident with the brass blade on my CC square, which I remedied by carefully sanding it straight again, on fine paper stretched very tightly over the tablesaw top.

My first attempt at a re-calibratible square turned out very well (mostly by good luck as I discovered when I made a few more!) I made one with a 350mm blade, because I'd always wanted a decent large square, but couldn't justify springing for the big CC model, since it is not an every day tool for me. Both for the reason above, & the fact that I had some suitable material, I decided to go with a spring steel blade rather than 1/16" brass. More bother to cut & make parallel, but should stand up to wear & tear longer (so far, it has). Since then I've made a few more, smaller models, using various woods for the stocks: Sq bits.jpg

It's not technically difficult, and about the only power tool you need is a good drill press equipped with a reasonably accurate vise, but you want an accurate tool, you do have to work very carefully (which means very slowly, for me!). The two steps that are the most difficult are drilling the stock for the setting screws, slugs & barrel nuts, and getting blades straight & parallel. I confess to getting one of the barrel nut holes slightly misaligned with its screw hole, on that first attempt. For once, luck was on my side, and the threaded hole in one of the barrel nuts was slightly misaligned; by flipping it the right way, everything aligned perfectly and it works smoothly. I think that's the only time in my life I've made a compensatory error! I still haven't worked out a foolproof method of drilling perfectly straight holes at a slight angle down a long, narrow bit of wood, & had to accept a wastage rate of about 1 in 3. Fortunately, it is only a very small scrap of wood, and I do that part first, so there is not too much riding on getting the holes right.

Getting the blade parallel is a much less fraught process, & I do that by careful sanding on a dead flat surface, until the edges are as straight as the human eye can detect, and a pair of calipers set firmly across the width at one end, slides along with the same resistance from end to end.

All god fun....
Cheers,

https://www.youtube.com/watch?v=jNEQ3AfJ94E

Here's my vote. I'm a huge fan of Colen's tools. But it's very hard to stop at one. I have a square, a 45° and three marking gauges. More to come.
My passenger to the Sturt School Expo thingy last weekend bought a CC T Square. I now need one of those too.