Review on 📐 Starrett 13C 6-Inch Double Square - Optimized with Hardened Blade by Mike Shah

This is a beautiful, accurate instrument and is the first Starrett I have ever held in my hands. Years ago I bought a Tesa Swiss caliper and one of their micrometers after the original owner passed away. This was my first exposure to precision instruments and they left a strong impression of the importance of accuracy and how easy they are to use. For years I got by with an inferior combination square and my guaranteed Incra square, but the former was cheap and the latter had no gauge marks. After reading the comments and exploring the options, choosing the 6" Starrett double square was pretty easy. As one guy said, cry once but smile for the rest of your life. All edges are perfect. It's about as square as I can tell if I hold it up to my incre to check. If I get a chance to put it on a granite reference block I'll update that. I was pleased to note that the blade was even and there wasn't a single burr anywhere. The movement is precise when the screw is loose. It glides precisely and without play. It closes tightly without excessive torque on the screw. And there is almost no gap between the blade and the head. I usually buy the highest quality American tools to help out my neighbors and I was very happy to find a certificate of inspection in the box showing it was made in Altol, Massachusetts. Here are a couple of unconfirmed measurements taken with a 6" Mitutoyo digital caliper and a 1" Tesa micrometer where I note the error using the attached certificate or the usual 1/2 smallest division. I wouldn't trust them with my life, but I take care of these tools as best I can. Length: 3.601 +/- 0.001 Head width: 1.1845 +/- 0.001 Head thickness: 0.5870 +/- 0.0025 Gap between blade and head: <0.0025 (my smallest pen) I have a small regret. The only choice was a shiny blade that scratches easily and is harder to see in the work light than a chrome blade, but I can still buy them separately. I give her 5 stars.