Step 7: Never Trust a Factory Edge Without Sqaring

When you buy sheet metal it will have crisp, straight (on some axis) lines. Before you start laying out a project, take the time to check the edges for square. I use an aluminum T-Square for this. A carpenter's square, machinst's square, etc. all work as well. This will save you from tearing out your hair after 4 hours worth of work when your project is 1/8" off center!

Another option if you're buying your sheet metal from a specialized sheet metal supplier, they can cut the sheet on a squaring shear, a huge hydraulic monster machine that makes perfect cuts.
Ive been a sheet metal worker for close to 20 years now. Went from old school techniques to modern equipment. This is a GREAT instructable. Very well done.
I wouldn't even try to weld galvanized metal, unless you want zinc poisoning haha.
pretty cool Bro , I learned more than a few things , well done man !
A thick Sharpie line before you scribe can help make the scribe line much more visible, though, and you can use different colours for bend, cut, etc. Excellent instructable, thanks!
Great instructable! Watchoutn when using HF hand seamer, I squeezed mine a too tight and broke it in half. I kept the bits to make a sand casting with in order to make a real Made in America tool in my home founfry.
Thanks! Most HF tools leave a lot to be desired in terms of durability. I'd love to barter for a home-cast hand seamer if you're casting some!
Very nice instructible, brought me back to a better day. As does just thinking about the glorious sheets of 060 stainless steel (with the edges so dul, gloves were merely a fashion statement) and 12 foot skids of clad and unclad aluminum stacked 15 + feet high, with brown paper sandwiched betwixt every sheet. Oh yes, those were the good old days and now that you've mentioned it, there's no reason they can't be relived a bit for old timer's sake. Thank you for this. One question; I've a pair of straight tin snips that need to be sharpened and perhaps tightened up, what type of edge should they have and how tight should they be etc. I think you are the person to ask. (if the good old days were still here I'd have a brand new pair)
My shears all have a single bevel edge that I touch up with files. I'm not sure of the angle. As for the tightness of the shear, there are many styles with their own specific tightnesses. My recommendation would be to pick up a set of thickness gauges like machinists use. Slide them into the joint on a pair that feels good to you and adjust accordingly. Happy metal working!
While this is a great instructables, there's two small thing I could suggest to help you improve it.<br><br>1. The scratch awl is a good idea to precisely trace a flat pattern on sheet metal, BUT I would not recommend using this method for any &quot;structural&quot; component. The reason is simple, you are adding weak spots all over the place,and they will sooner or later result in fractures.<br><br>2. You probably did this for the convenience of it when cutting your metal, but the &quot;sharp corners&quot; on your flange near the bending lines are also weak spots waiting to transform in fractures. You can easily drill a small hole in those corners before cutting the metal with your snip to create small radiuses that will help increase toughness.
looks like the engineer's toolbox (i know its not, its an older design of a toolbox)
Excellent instructable, truly
Thank you for a very fine, useful Instructable. I am thankful to have a welder, but find there are times when my pop rivet gun is the better choice. As regards &quot;free&quot; metal, we recently replaced a water heater. The old one is full of lime and heavy. I am cutting it up in pieces before trying to haul it up the basement stairs. The outer shell is a nice gauge of sheet steel I want to use for various projects, including some small parts trays. I hope your Instructable is featured and makes the newsletter.
Thanks! To make that outer shell lay flat, you can &quot;cross break&quot; the sheet using a break press. Make an X across the sheet, then a box around the perimeter and it will lay flat.
Nice intro into becoming a diy tin knocker, thanks.<br>I have been thinking about making a small brake and trying my hand at it.
If you just want to get a feel for sheet metal without a huge investment, there are tool called &quot;bar folders&quot; which are basically a hinge that bolts to a surface with a machined-flat piece of bar stock that you clamp over the material you want to bend. Bend the piece up to the desired angle. Harbor Freight has one for $40: http://www.harborfreight.com/18-inch-bending-brake-39103.html
This is a great intro to working with sheet metal! I learned a ton.

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Bio: I'm a compulsively curious guy. I have taken things apart all my life, intrigued by how things work. I didn't know other tinkerers ... More »
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