When AC stick welding on an I beam in hot weather I had an arc strike down my forearm that was holding said I beam. My welding gloves and leathers had gotten pretty wet with sweat and lost insulating properties with sweat being conductive. What amazed me was the distance the arc jumped to my arm. My hood was up and I swear it cleared a 3 inch gap. When I popped my jacket off I could see 4 little burn marks where I assume the AC wave changed polarity. My saving grace was the current flowed out my hand and not through my torso and the swinging motion I was making continued and opened up the gap enough to stop the arc. Moral of that story either keep your welding gear dry or don't hold the workpiece (which in this case wasn't an option).
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Goofs & Blunders You Should Avoid.
- Thread starter David S
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On a large lathe holding a large part it is difficult if not impossible to rotate the spindle by hand, this is especially true if you are indicating 60" from the spindle as there is nothing to hold onto on a round part, I gear the lathe slow and jog the spindle around.
As a disclaimer I have never watched a how-to machining video. I have no problem running the spindle at speed with an indicator on it, however I do a good deal of large parts where max spindle speed is less then 200 RPM,s.
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I learned just 10 minutes ago that you probably shouldn't drain your air compressor into a pan just used to brake-clean parts. Especially when you open the valve too far and blast the contents onto your face, chest and arms. Oh well, the shower felt good and the safety glasses I had on felt even better!
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Not recent but a long time ago when I was young dumb and thought we were invincible, welding a small section on a car body, No gloves on, one hand and the car and grabbed the lead, Well just so happened that it had a bad spot on the handle, Did not get the rod close to the car, but the hand that I was using to steady myself on the car, had on my wedding ring, Boy did I jump and everything, Had fun pulled my finger out of the wedding ring as it was stuck to the car, blister from hell on my finger. It took me a long time before I would get close to the welder again, It belonged to someone else, and they had to get it fixed and prove that it was fixed before I would even get near it. Now wear gloves even on hot days, but from what Wreck Wreck said I may want to keep some dry spares around. By the way the wife told me not to wear my ring as long as I was working on things all the time. Did buy a new one but still have the old one just because.
Now I am wandering if that is not part of the reason my heart is not quite like it is supposed to be.
Now I am wandering if that is not part of the reason my heart is not quite like it is supposed to be.
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I'm not convinced that this is either a goof or blunder. Seems like something quite unexpected and perhaps even unforeseeable. Good lesson, though.
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Blunder last week, had to bore into a recess in an existing part for a repair, couldn't get the #1 tool into the recess to set the Z axis position (the #1 tool is what all other tool offsets are based on) could have put a gauge block in the recess against the shoulder and touched off the 1 tool on that to set Z. But no, it was a rush job and I am lazy so I touched off the boring bar an inch or more inside the end of the part and reset the bar Z offset to zero.
With predictable results from doing such a thing several hours later using the boring bar on another job I forgot about the 1"+ offset difference and rapided it to .100" from the end of the part, naturally it crashed at 100" inches per minute feed rate, broke the insert and rotated the tool post. Then had to spend an hour or more squaring the tool post, setting the work shift for tool 1 and resetting the offsets for 23 other tools, a real time saver. The good thing is that I never rapid a tool to the start position with the spindle running.
With predictable results from doing such a thing several hours later using the boring bar on another job I forgot about the 1"+ offset difference and rapided it to .100" from the end of the part, naturally it crashed at 100" inches per minute feed rate, broke the insert and rotated the tool post. Then had to spend an hour or more squaring the tool post, setting the work shift for tool 1 and resetting the offsets for 23 other tools, a real time saver. The good thing is that I never rapid a tool to the start position with the spindle running.
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Sounds like the time my ex lost the keys for the disc lock[1] on her Yamaha - careful "shielding" the bike before making lots of sparks with the angle grinder, remains of the lock fall off after 5 minutes (those things are Hard and Tough - maraging steel!), she dives in with both hands and grabs the pieces, past my hands in heatproof leather gloves... She spent the next week smoking store-bought, couldn't roll cig's for the blisters
[1] a small shackle lock with a pin through the front brake disc, to prevent "roll-away" thefts
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some good lessons learned in this thread already, but I guess I'll add a few of mine as well.
Had just gotten done converting my PM45 mill to CNC and was excited to make some chips so I cut a part without the chip guard covering the Y axis ball screw (mistake #1). Being completely absent minded I though I'd clean the chips off the ballscrew before going onto the next tool. Stuck my fingers down there (mistake #2) to get the chips, and jogged the machine (mistake #3) to make the ballscrew rotate. Well the machine did exactly what I told it too, the ballscrew rotated and the saddle moved towards my finger. Almost sheared my finger off between the base casting and the saddle....rookie move...
Next one happened while replacing the suspension bushings in my buddies RX7. Tried pressing the bushing out of the rear a-arm, and the center of the bushing pressed out while leaving around 1/4" of rubber still on the a-arm. Being young and stupid I decided to take a sanding drum on a dremel and grind out the remaining rubber. Ok, worked like a charm....until a piece of molten rubber flew into my face and landed just under my eye. For those of you who have had molten rubber on you know it sticks to skin VERY well. Of course I wasn't wearing safety glasses. I ended up waiting for the rubber to cool and peeling it off, subsequently taking a few layers of skin with it.
But did I learn my lesson...of course not, I am invincible...Several years later I was cutting a bolt with one of those thin cutting wheels for the dremel (you can see where this is going) the wheel broke and sent a piece of itl flying right into my eye. There must be a god out there because at that very second I had blinked. The wheel hit my eye lid, and while it hurt like a bastard, it didn't cut/scratch/or otherwise effect my eye.
lessons learned:
1) don't be stupid!
2) patience pays off
3) wear safety glasses at all times in the shop, no matter how quick the job
4) wear safety glasses outside the shop too!
did i mention safety glasses? Use them!
Had just gotten done converting my PM45 mill to CNC and was excited to make some chips so I cut a part without the chip guard covering the Y axis ball screw (mistake #1). Being completely absent minded I though I'd clean the chips off the ballscrew before going onto the next tool. Stuck my fingers down there (mistake #2) to get the chips, and jogged the machine (mistake #3) to make the ballscrew rotate. Well the machine did exactly what I told it too, the ballscrew rotated and the saddle moved towards my finger. Almost sheared my finger off between the base casting and the saddle....rookie move...
Next one happened while replacing the suspension bushings in my buddies RX7. Tried pressing the bushing out of the rear a-arm, and the center of the bushing pressed out while leaving around 1/4" of rubber still on the a-arm. Being young and stupid I decided to take a sanding drum on a dremel and grind out the remaining rubber. Ok, worked like a charm....until a piece of molten rubber flew into my face and landed just under my eye. For those of you who have had molten rubber on you know it sticks to skin VERY well. Of course I wasn't wearing safety glasses. I ended up waiting for the rubber to cool and peeling it off, subsequently taking a few layers of skin with it.
But did I learn my lesson...of course not, I am invincible...Several years later I was cutting a bolt with one of those thin cutting wheels for the dremel (you can see where this is going) the wheel broke and sent a piece of itl flying right into my eye. There must be a god out there because at that very second I had blinked. The wheel hit my eye lid, and while it hurt like a bastard, it didn't cut/scratch/or otherwise effect my eye.
lessons learned:
1) don't be stupid!
2) patience pays off
3) wear safety glasses at all times in the shop, no matter how quick the job
4) wear safety glasses outside the shop too!
did i mention safety glasses? Use them!
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CS your eye one reminded me of one form abut 30 years or so ago, Remember the old big VHF antenna that you use to have on the roof.
Well got up there to do something, did not realize the pole was loose, it was windy I turned around just as the big gust of wind rotated the Antenna. One of the Aluminum rod ends right in the eye,
needless to say I had fun getting off the roof. Got in side tears running down my face, looked in the Mirror and could see the gash across my cornea. WEll, drove to the local clinic, they then chewed me out and put me in an ambulance to take me across town to the ER. WHere I got it again. Then when I got out had to find a way back across town to get my car. Which they did not want me to drive. What was bad my glasses are safety glasses, and did not have them on that day. I have been told that I am accident prone or an Accident magnet.
Expect the unexpected.
Well got up there to do something, did not realize the pole was loose, it was windy I turned around just as the big gust of wind rotated the Antenna. One of the Aluminum rod ends right in the eye,
needless to say I had fun getting off the roof. Got in side tears running down my face, looked in the Mirror and could see the gash across my cornea. WEll, drove to the local clinic, they then chewed me out and put me in an ambulance to take me across town to the ER. WHere I got it again. Then when I got out had to find a way back across town to get my car. Which they did not want me to drive. What was bad my glasses are safety glasses, and did not have them on that day. I have been told that I am accident prone or an Accident magnet.
Expect the unexpected.
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- Apr 26, 2014
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About a year ago I made a 1" arbor for my Rockwell 21-100 mill to use this blade with:
It has worked great - cut through 1.5" 4140 bar stock. A marvel of modern cheap carbide.
Turns out if you accidentally put the mill in reverse, even to touch off, you harvest a small pile of 28 teeth. Harvest time was tonight! Time to order another one!
It has worked great - cut through 1.5" 4140 bar stock. A marvel of modern cheap carbide.
Turns out if you accidentally put the mill in reverse, even to touch off, you harvest a small pile of 28 teeth. Harvest time was tonight! Time to order another one!