Yesterday I took a 2×4 and my angle grinder with the diamond cutoff wheel, and snapped a couple of “here’s why not” pictures.
It was so depressing I decided not to post them. Also, they didn’t look like much – a bunch of shredded wood with some deep cuts in it. It would have been more illustrative if I’d gone and ruined some steak but that would be an uncool waste. So I’m just going to preach at you without supporting illustration.
This is a screen shot from a video by one of my favorite youtubers, a Ukranian metal artist who goes by “shurap” (Yevgeny Shevchenko, I think it is) [yt] I know he knows what he’s doing and the fact that he was able to post a video at all tells me that he completed the exercise safely. But it made my flesh crawl to watch it.
First off, cable is nasty stuff to cut with a grinder, in the best of circumstances. Secondly, the fact that he needs to support the cable with his hand means it’s likely to droop and the cutoff wheel might bind. If that were to happen, where does the grinder and the cutoff wheel go? Yep, right into the plumbing on the inside of his wrist.
Now, he’s strong as hell (look at those hands!) and he’s got a good choked-up grip on the grinder and is working close to the vise, etc, but given all of that he could have just as easily positioned the work-piece vertically in the vise and had no problem at all. There’s a really simple rule for angle grinders: if you always hold them horizontally, they can never kick vertically – which means that they can only hit the person standing next to you. So, never have anyone else in the room and always hold it horizontally (use the support handgrip, too) and you cannot have it kick in a direction that includes you.
Back when I did internet security for a living, and before when I wrote code, I discovered that I’m unusually good at seeing how things are likely to go wrong. I guess it’s just how I learned to think, probably a result of too much strategy gaming and playing too much chess. It was probably the chess: my chess-playing is an exercise in “all the things you can do wrong” and you’ve got the entire end-game in which to perform your damage assessment. I always seemed to be able to walk into a situation and tell my client the top 5-10 things that were most likely to bite them, and how to avoid them. Then, years later, I’d return to manage the incident response and it was always, “now that you have done that thing I told you not to do, and it bit you, let’s see what we can do to undo events.” If my life-experience were to hold true that means Shurap had better “waste” a few seconds managing his work-piece a bit better, or we’ll see his youtube channel go dark and silent for a few months while he heals. I’m trying to be a bit “light” about this, but I’m deadly serious.
Here’s another one, from another hero of mine, Walter Sorrells. He is demonstrating putting a grabby new 38-grit abrasive belt on a grinder, and then reaches across the belt to turn it on:
That’s a 2 horsepower motor with a capacitator start: they turn on and they’re going and, if his sleeve caught on that belt, he’d be lucky if his shirt disintegrated before his arm did.
When you’re working with any tool, it’s a good idea to leave everything turned off and take a look around, then mime your normal operation with the tool and see if there’s anything you haven’t noticed. For example, I have a heavy rubber mat on the floor in front of my Bridgeport milling machine – because I don’t want there to be any reason I’d suddenly lean forward to catch something before it falls on the floor; now I can just let it hit and it won’t break. Extra plus: if something rockets off the mill and toward the floor at high speed, it’ll dampen the bounce. I’m not worried about that because milling machines operate horizontally, which means I am mentally prepared to get below the plane of the mill at any moment. For $45, you can bet there’ll be a big rubber mat in front of my metal lathe, for the same reason – lathes operate vertically, which means you’re a target. And that photo of Walter is a case study in how to self-inflict death by lathe.
I’m not saying this to criticize these people, who I hold dear. This is more to serve as a reminder to myself that you can never be casual with machine tools. Or, machines in general. As I’m setting up my new shop, one of the things I have been doing is running over and over through my head, to visualize my work-flow and make sure that there are no things I can trip on, that can grab me, or set me on fire. Back in 1981, when I got my first motorcycle, Fred M, who taught me how to operate the thing, told me “always ride as if the cars around you are going to suddenly try to kill you.” Fred’s advice saved me a great deal of pain. I think I’ve internalized it to the point where a part of me acts as though the Bridgeport might suddenly turn itself on while I’m changing mills. Who knows, when the machines rebel, it might.
I use a diamond cutoff to chop chunks of my 1 1/2″ high carbon wire rope. That makes a tremendous mess and it’s hard to arrange things so I can come at it horizontally, but – I do. Even if it means shifting the entire 750-lb spool. I like my fingers that much! Also, when cutting wire rope, have a small roll of cheap utility wire and some pliers; take a turn around the wire rope and twist it tight, so the wires won’t try to untwist. It takes a few seconds and you waste 8″ of wire. Once you’ve got it cut it won’t untwist when you put it in a vise and tack the top and bottom together with your MIG welder.