I am taking a fabrication class at Washtenaw Community College
this term. The prerequisite for the class was a whirlwind tour of all the different kinds of welding there are — more on that later. Suffice it to say, I am now capable of barely welding four-inch lengths of very specific materials under absolutely ideal conditions.
The description for the fabrication class is, in part, the following:
For advanced welders
[Hahahahahahahahahahaha!] planning to use their welding skills in manufacturing, this class teaches the skills necessary to design, cut and fit pieces to be welded. Welders are trained in the use of modern machines for bending, punching, cutting and shaping.
Despite the emphasis on welding in the class description, our first project was a toolbox made out of 20 gauge steel sheet, put together with folds and bends that are used all the time in things like duct work, plus a few rivets. No welding at all. With a few minor exceptions, we followed the tool tray project in the back of what seems to be the standard book for sheet metal in the US, Sheet Metal
by Leo A. Meyer. (Note that the book has been around for at least twenty years, published under slightly different titles with the various editions. I haven't seen the most recent edition.)
The tray looks like this (be sure to click on the image for a big picture):
I've been told that job applicants in the field of fabrication of stuff and things are often handed some sheet metal during a job interview, and are pointed to the shop: if they are able to build a well-made tool tray, they get the job.
You may have noticed that the book, and most people, call this object a tool tray, not a toolbox. In fact, Mr. Meyer has plans for building a toolbox in his book — complete with lid, hinges, latches, and tool tray that fits inside. (The tool tray I made is the first of the "Supplementary Projects" in his book; the toolbox complete with a slightly different tray design is next to last.) But the folks at the community college call it a "toolbox," so toolbox it is. Here is mine, after Paul at Cramer Tech Coating, Inc.
threw it in with a real powder coating job, and gave me a very nice price. Thanks, Paul!
Once again, I have made something that is difficult to photograph, this time because of the matte black finish. (You can click on these photos for larger versions.) No worries, it's beautiful in real life. The powder coating makes a beginning shop class project look like a real, professional thing.
I have to say, it's really fun to start with a flat sheet of metal and turn it into something useful. Here are some details. The box is made of three pieces of metal: two end pieces, the handle, and the bottom-and-sides. You can click on these for larger versions.
The handle is attached to the end pieces with pop rivets (also known as blind rivets). The end pieces are held in place by "Pittsburgh seams," which are formed along the bottom-and-sides. In the real world, there are machines that make these seams quickly and easily, but we had to put them together with the bench brake and whacking by hand with a mallet.
This is how the Pittsburgh seam is made: in these two sketches, the end pieces are being slipped in on the right, and the bottom-and-sides, with all the folds to accept the end pieces are on the left. Once the end piece is in place, that last fold from the bottom-and-side is whacked over with a mallet.
These sketches are taken from another book by Leo Meyer — who has apparently written all the books you'll need for learning about fabrication, plus a few more — Sheet Metal Layout
. This one is out of print; I got both books at my public library.
Despite appearances, my toolbox isn't finished yet — I'm adding some embellishments. More to come.