advice for a big try square

[BrentDH]

I have had the need several times in the past couple months for a big (18" to 24") square.  The biggest use would be for setting up the track for a track saw to cut sheet goods or checking squareness on large panels.  I have a decent 8" try square but that seems to lack accuracy over a 4 foot cut.  I also have a few crappy framing squares that cannot be trusted at all.  Woodpeckers makes the perfect tool for the job but as with most of their tools they are VERY proud of them (ie they cost a lot).  Is there something between a stamped $5 framing square and a $240 Woodpeckers 2616?
https://www.woodpeck.com/woodpeckers-26-...uares.html

[Roly]

I have had the need several times in the past couple months for a big (18" to 24") square.  The biggest use would be for setting up the track for a track saw to cut sheet goods or checking squareness on large panels.  I have a decent 8" try square but that seems to lack accuracy over a 4 foot cut.  I also have a few crappy framing squares that cannot be trusted at all.  Woodpeckers makes the perfect tool for the job but as with most of their tools they are VERY proud of them (ie they cost a lot).  Is there something between a stamped $5 framing square and a $240 Woodpeckers 2616?
https://www.woodpeck.com/woodpeckers-26-...uares.html

I use a drywall T square. Maybe I was just lucky but a brand name seems to be very accurate and 48" long.   Put the "T" on a straight side the draw a line and flip square over draw another line and they should be parallel.  Roly

[only 3 injuries]

Ii took a hard look at the woodpeckers square, but couldn't justify it it. I don't mind paying for quality, but it just didn't seem like something I would use enough. So I ended up making a large Seaton square (well, several at a time, the others were gifts).

Just costed me some time and stable wood. Plus gave me a some good practice with joinery.

[Cooler]

This Shinwah square is supposed to be highly accurate and manufactured in Japan. 

https://www.amazon.com/SHINWA-sliding-ad...52&sr=8-42

This is the large size (60 cm = 23.622").  They make a 45cm and a 30cm version too. 

I folds to a single stalk.  It would be my first choice over the Woodpeckers.

A note about Woodpecker's finish.  They do not use a UV-resistant anodizing dye.  Do not leave their red measuring tools out in the sun or the color will disappear on you.  

You set the angle you want:

[MT Woodworker]

I also use a drywall T-square, I have a 48 inch and a cut down 24 inch.

[KyleD]

You could start with a $5 framing square and turn it into a good tool for your purposes. Make sure the long leg of the square is straight and smooth then add a straight wood fence to the short side. Basically you are turning it into a large tri-square. you will have to cut a kerf in the wood fence as wide as the square is thick then figure a way to sturdily attach it. Use the make a line then flip and make another line method to align the fence. Maybe some epoxy in the kerf then a couple of brass rivets would work well for keeping the wood fence in place.
I found an article that basically does what I am trying to explain- https://www.woodmagazine.com/woodworking...try-square

I would not cover the entire metal leg of the square as the article does. If you leave a little of the metal square edge sticking out on the inside it sits on the material. The square does not want to pivot down when not being held.

[iclark]

You could start with a $5 framing square and turn it into a good tool for your purposes. Make sure the long leg of the square is straight and smooth then add a straight wood fence to the short side. Basically you are turning it into a large tri-square. you will have to cut a kerf in the wood fence as wide as the square is thick then figure a way to sturdily attach it. Use the make a line then flip and make another line method to align the fence. Maybe some epoxy in the kerf then a couple of brass rivets would work well for keeping the wood fence in place.
I found an article that basically does what I am trying to explain-     https://www.woodmagazine.com/woodworking...try-square

I would not cover the entire metal leg of the square as the article does. If you leave a little of the metal square edge sticking out on the inside it sits on the material. The square does not want to pivot down when not being held.

I did not know about the Shinwah squares. Thanks, Cooler.

KyleD's solution can work well once you tweak the squareness of the framing square.

You can use a prick punch (or a regular punch and hammer) to tweak the framing square to be square as long as the arms are both straight. When making the adjustment, it is a good idea to make the adjustments symmetrically on both sides of the elbow.

I highly recommend that you pick one of your "crappy" framing squares that has pretty straight arms and practice on it. Then use a sharpy or some fingernail polish to label it as your "good" framing square. Normally, it will stay square until the next time that you drop it or pack too much stuff on top of it in your car. DAMHIKT

[jteneyck]

I've made several 3-4-5 squares as well as a couple of T-squares out of plywood to fit whatever job I needed them for.  I rip 1/2" plywood to whatever width seems appropriate for the size I need, generally around 2 to 2-1/2", and then glue/screw them together.  I drive one screw then check to make sure the 90 degree angle really is by drawing a line along the edge, flipping the square 180 degrees and drawing another line on top of the first.  The two lines should be one line; any deviation means it's not really 90 degrees.  Once I'm sure it's truly 90 degrees, I clamp it until the glue dries then drive another screw or two to make sure it stays that way.  

John

[MstrCarpenter]

I use a drywall T square. Maybe I was just lucky but a brand name seems to be very accurate and 48" long.   Put the "T" on a straight side the draw a line and flip square over draw another line and they should be parallel.  Roly

When my drywall T-square isn't square, I just gently tap into square. The thicker ones generally stay square longer, but if you're actually using it for drywall, it's going to hit the deck a few times so adjustment becomes necessary. I was marking some crosscuts with my brother's T-square when I noticed the 6" side was a little short. Seems he was using it as a saw guide when it happened. He thought of it as an accident, I thought it was a great idea! No more measuring offsets and using another straight edge. I hook the square on the far side of the sheet with the "cut end" on my mark, pull and clamp the close side, then cut. He uses the same saw as I do, bonus!

[BrentDH]

Thanks guys.  Some good ideas to consider here.  I had seen the idea once where someone took wooden strips and attached them to the short end of a framing square, but had forgotten it until it was mentioned here.  I also completely understand the theory of setting the wooden strips back from the edge so that the square is supported when sitting on the edge of the wood.  That was an appealing characteristic of the woodpecker square (in addition to the accuracy) and there is no reason one couldn't do the same with the wooden attachment to a framing square.  Thanks again for the input.