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Advanced Metal Sheering Tips and Tricks - Cuttin' CornersMetal Shearin' Made Easier From the February, 2010 issue of Rod & Custom By Rob Fortier
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There's a huge difference between the desire to save time and just plain laziness. While I have been known to get the two mixed up on occasion, when it comes to any type of metal fabrication, I've grown quite fond of any tool or device that's not only good, but can cut some serious time off a particular process. In this case, the cutting's literal-we're talking shears ... old-school and new
fangled. Sheetmetal shearing is one task that I haven't ever been a really big fan of, well, at least until recently. Having some pretty serious arthritis, it's not much fun trying to cut a chunk of 18-gauge with a pair of snips, even if they are sharp. For casual use, tin snips were really the only choice from an economical standpoint. And, for the most part, they did (and do) the job-on my hands as well! Looking for a reasonable solution somewhere in-between the hardware store cutters I was using and a big ol' industrial shear, by chance I stumbled across Woodward Fab's throatless rotary shear while thumbing through the latest Summit catalog I'd received in the mail. If you're familiar with these, then you know how nice they are for making straight, angled, and (as advertised) curved cuts on up to 1/8-inch material (I think cutting that thick will wear the blades down real quick). Best of all, they're under $200. Once I familiarized myself with it, I probably wasted more pieces of sheetmetal than I should've just messing around. For a couple hundred more, you can always step up to a "good" Beverly shear, but that was my problem-didn't have an extra couple hundred. Regardless, for the amount and type of cutting I do, the rotary will do ... just fine. While not quite as inexpensive as the rotary shear (roughly twice the cost), another time-saver tool I found that works equally well-and much better than snips-is the Excalibur 14.4-volt cordless sheetmetal cutter. Unlike a typical pair of electric shears, such as the Milwaukees shown, these cut just like a manual set in that they don't waste any material in the cutting process. The blades (which can be sharpened) will cut up to 16-gauge mild steel and 18-gauge stainless. Designed and manufactured in Australia for the roofing trade, these work great for light and heavy automotive sheetmetal fabrication. For the money you spend, you also get a charger, extra battery, and carrying case, so when you add it all up, it's not a bad deal. Still, if money is a real concern, which is for most of us these days, then there's absolutely nothing wrong with the tried-and-true snips. For very occasional use, the Harbor Freight ones definitely do the job. However, for more frequent use and more precision, I've found the Prosnip brand works exceptionally well-far better than the typical hardware store ones from Wiss-and are priced right. I've had my yellows (straight cut), reds (left cut), and greens (right cut) for who knows how many years, and to this day they're still one of the most-used tools I have ... that is, when I'm not using one of my new time-savers to save my hands and actually try to finish a job!  For anyone who does a decent...  For anyone who does a decent amount of sheetmetal work, it's hard to beat this tool. Woodward Fab's throatless rotary shear can cut circles around your old tin snips-literally. The forged steel frame is heavy, but the ratcheting shear can perform some heavy-duty cutting.  For first-time users, it might...  For first-time users, it might take a bit getting familiar with, but all in all, the rotary shear is fairly straightforward: the material feeds in with the ratchet to the left; usable piece should also be on the left.  Regardless of whether you're...  Regardless of whether you're right- or left-handed, you can feed/guide material with one and work the blades via ratchet with the other. For longer cuts, make sure the excess metal is directed through the "throatless" portion of the shear, as it's possible to get shorter pieces bound up.  While my skill level's indeed...  While my skill level's indeed a factor, I was unable to get nice, even radiused cuts like this in heavier gauge sheet using snips. The rotary shear definitely takes a lot of effort out of the equation too. The more pronounced teeth marks (concave piece) only result on material fed to the right of the blades.  The rotary's blades are adjusted...  The rotary's blades are adjusted with a hex-head cam-if the cam's not tightened completely, you'll notice right away as the blades spread apart once you start feeding the material.  Powered handheld shears are...  Powered handheld shears are great, except if you want them to cut like snips without material loss caused by the blades (which isn't necessarily a big deal). If that's the case, the Excalibur cordless sheetmetal cutters will do the trick.  These Aussie-made cutters...  These Aussie-made cutters feature a cam-driven, adjustable head (rotates). They're reported by the manufacturer to cut up to 12 inches per second, and can cut up to 300 feet of mild tin on a single charge of its 14.4-volt battery.  Cutting is almost effortless...  Cutting is almost effortless and smooth as silk-as long as you keep the cutters cocked between 10 and 15 degrees.  If the excess metal doesn't...  If the excess metal doesn't feed out properly, it'll not only bog down the blades but produce a poor cut as well.  The smaller vertical cut is...  The smaller vertical cut is the result of a sufficient pass; the longer horizontal cut is characteristic of what happens when the cutter is not angled/guided properly.  With a fresh set of blades...  With a fresh set of blades installed, my 110-volt Milwaukee electric shears work just fine for straight and slow curving cuts. I picked these up at a yard sale; don't think I'd own them otherwise, as I'd much rather spend the money on something like the aforementioned Excaliburs, for what it's worth.  Plus, I'm tired of picking...  Plus, I'm tired of picking up-and oftentimes stepping on-all the sharp curly cues the Milwaukees make! If I need to cut a large piece of sheetmetal in half, though, the less distortion they cause will more than likely rule out the cordless ones.  Don't get me wrong, I'm not...  Don't get me wrong, I'm not all "pro" professional tools. If money were the deciding factor, my set of Prosnips would definitely suffice-I've used them for this long, and I know they've still got a lot of life left in 'em!  In all honesty, one could...  In all honesty, one could really get away with simply having just one set of tin snips-the yellows, or straight-cut (Prosnip 103) snips.  But for more accurate "right"...  But for more accurate "right" and "left" cuts, why not have the reds and greens too?!  In addition to the red, green,...  In addition to the red, green, and yellow snips, often referred to as "aviation" snips, are these "offset" snips. These are from Snap-On (left) and Wurth (right) and are a little more expensive than the aviation snips. Note how the jaws are offset to one side. These snips are available in straight, left, or right cut, just as the aviation snips are. The Wurth snips shown can handle steel up to 1.8mm thick. These are twentysomething years old and still going strong, though the blades have seen some abuse over the years!  Note how the offset jaws allow...  Note how the offset jaws allow the steel to be trimmed off to "curl" while the work piece remains flat. The angled jaws also keep your hands away from the sharp metal edges as the handles are up and away from the sheetmetal.  No matter what you use to...  No matter what you use to cut with, protect your investment-keep the blades lubricated all the time. I've been using Rapid Tap on everything from tubing cutters to drill bits (and of course shear blades) for quite a long time, and it's kept the tools I don't break in service for quite a long time as well.
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