StarrettSteel Combination Square with Square Head - 12" Blade Length, Cast Iron Heads, Reversible Lock Bolt, Scriber, Spirit Level, 4R Graduation Type - 11H-12-4R

Starrett's 6" inch combination square is regarded by many as a the best on the market. I haven't evaluated any of the other high end squares, but to my mind it is nearly flawless. Why do I think this?It is square, not kinda' sorta' square if you hold it right. I mean square to the point where you can't detect any light between a machinist's reference block and the body or blade even with strong backlighting. Your eye can see light from a 0.001" opening so you know the square is at least this square.You can tighten the thumbwheel using only one hand to achieve the squareness described above.The numbers and lines are engraved so they don't wear off. The engravings are deep enough so that you can put the points of your dividers in them to accurately set the distance between the points.The satin finish on the blade makes it easy to read.The "4R" marking system (1/8, 1/16, 1/32 and 1/64) is more useful than you might realize. It cuts down errors due to misreading the scale and is faster.Reinserting the blade after removing it from the body is easy. On some squares, this is a major hassle. On the Starrett, the protrusion in the body which holds the blade generally stays in place when you remove the blade. If it gets misaligned with the slot, it is easy to rotate it back to parallel with the body so you can reinsert the blade. The spring holding the protrusion has the proper amount of stiffness.Another good thing is that it is rugged. I haven't hit it with a hammer or put a torch to it, but it has suffered a lot of drops onto a wooden floor without damage.Why don't I think it is perfect? It will rust (like almost all steel) if you don't take care of it. By taking care of it I mean storing it dry, free of salt from sweat, and dust. Not a big deal, but this is a precision square so treat it with the care it deserves.A wise man once said, "When you buy quality, you only cry once." Do yourself a favor and buy this square.

This is one of those unique tools that lives in a special place in my cabinet. It reminds me of a different world where craftsmanship and engineering reign supreme. Why the superlatives? Because it is more than a very well made, very accurate, high-quality combination square: It is because when I take this tool in my hands, I FEEL (add emphasis) different, and I work differently because of it.Corny, you say? It's just a pricey combination square, you say? Perhaps. But for me, there are only a handful of tools in my collection that evoke an emotional response whereby their very use transports me back to my grandfather's shop, where I can feel the textures, hear the machinery, and smell the varnish, dust, motor oil and age. This is one of those tools. It makes me nostalgic for an age- real or imagined- before outsourcing and cheap tools, when quality was the norm. This combi square simply looks and feels different than many of my other layout tools, aside from being more accurate and precise than any of them. It looks... machined.Enough of waxing emotional. this is a high quality, precision tool that belongs in your tool box if you need that kind of precision (squaring-up your miter saw or table saw, for example) and can afford it. I notice that this is now going for thirty bucks more than when I bought it two years ago. Yikes. Is it thirty bucks better? I doubt it. But then, I'm devoting five stars to this tool in part because of how the quality makes me feel, not just whether it is worth the dough for something that is very, very square and well-made.Would I recommend this tool for someone just to use for framing houses or building chicken coops? No, I wouldn't, as there'd be less bang for the buck there versus other combi squares that are square enough and go for far, far less. I would wholeheartedly recommend this, however, for those who need a precise layout instrument that will last, that has smooth, well-engineered action, and is dead level, square, and straight... And that makes you feel good just by holding it.

In science, one is quickly taught that errors accumulate geometrically, not linearly. So perhaps that is why I felt no buyers remorse in paying the price for a proper Starret square. I now have the confidence that when I strike a line or square an edge, it is true every time. I dumped all my crummy Stanley squares (not before measuring them against the Starret and finding all of them out of square by some degree and with imprecise straight edges) and now, all of a sudden, my marks all line up when I strike lines for through-mortises.Starret IS precision. Everything about it is finely finished, perfectly engineered, and beautiful. It feels heavy and as solid as a block of granite in the hands. There is no slip, no jiggle. The grade marks are impressed and deeply embossed, easy to read, fine and accurate. The forged body and rule came polished and satin, respectively, and no touch of rust, pitting, or scratching has showed up after weeks of daily use, and a few hard falls onto an oak deck that had my heart pounding- until I realized just how bullet-proof an all-forged Starret really is.For the beginner woodworker, spending 100+ on a ruler seems.. prohibitive. Foolish. Surely a 25 dollar Stanley can do the job? Well, I don't think it can. You can make a straight cut with a 20 dollar saw, and plane smooth with a 15 dollar yard-sale Stanley 4- but not if your measures are off. A good Starret is the foundation for all clean, accurate work, the only way to confirm your planes are flat, your chisels are square, and your stock is jointed proper. Save money any way youcan- but not on the one tool that everything else in your shop is measured against.