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Goofs & Blunders You Should Avoid.

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master53yoda

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I had a nerve on the outside of the cut that finally callused over but for probably 5 years it was just like getting shocked with 110 every time i touched it
 

Bill Gruby

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Been there bdone that. It isn't close to being funny.

"Billy G"
 

brino

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man I wish there was a "delete post" button on this site!
or at least a way to add quotes during an "edit" of a already posted response.
-brino
 
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brino

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Why would one use a volatile, flammable liquid as a coolant for a tool that has an open ignition point (that is, the spark)?
The kerosene works extremely well as long as the ignition point is kept submerged.
exactly why I decided on distilled water for my EDM.......I can't be trusted! :oops:
(@savarin, it is not meant as a gloat or "I told you so", just as a example of a compromise/substitute for safety's sake).

Yes my EDM vise is rusty, I want to try a wax coating or something......

-brino
 
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brino

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Lots of things are flammable in a dust or powder form----try a little coffee creamer powder--burns well
Even many things that are not flammable can be explosive when in dust form.
I've never seen it for myself but I remember a story about a table saw being used for cutting steel & apparently pine dust is much like gasoline.
I spent some school-time summers working mechanical maintenance at a plant producing diapers. They had large towers for both storage and processing("fluffing") of talcum powders. They went to great lengths to make sure that even a static spark could not ruin everyone's day.

Myth Busters did a huge fireball with "coffee whitener".......and saw dust, and other common powders.

Be careful out there!
-brino
 

Glenn Brooks

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Reading through the thread, saw a couple of posts about welding sparks pitting windshields on cars in the garage. This reminded me of a small welding project I did two or three summers ago. I always wear protective gear when cutting or welding -summer and winter. So took off a nice new fleece pullover, and put on my old leather welding jacket. Buttoned it up to the neck, doned the gloves and hood and went to work. About 10 minutes later I had welded the fixture up and took off the leather coat to put everything away. As I turned around, I noticed my nice new pull over fleece I had folded up and placed behind me on the ground, out of harms way, had turned into a small synthetic bonfire. The flames had burned a nice hole right thru the center of my garment, right down to the pavement. Somewhere along the line, welding sparks had somehow bounced into the fabric and ignited. I stamped the fire out. But holding up the pullover, could see nothing left except the arms, neck, and zipper, and a bunch of ragged, burnt and melted fabric around the edge of the garment, with avery large hole burned clean through the body.
 

SapperDave

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When using an angle grinder on an I beam on the floor, do not kneel down when your cutting. Having a diamond blade run up your inner thigh hurts, Stitches in your inner thigh hurt even more, especially if you do it the day before your first holiday in years. It was fun explaining to my wife why I was in the medical centre.
 

mephits

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Apologies to all for taking so long to respond. My wife had surgery at the beginning of the week and I've been a little preoccupied. It was a routine endoscopic procedure that went beautifully, but she still had some recovery to do afterward. She's fine now!

Liquid kerosene will not burn. Like gasoline, and diesel, it needs to be mixed with oxygen to support combustion. Gasoline appears to burn, because it vaporizes easily, and that is what you see burn when you toss a match in a bucket of gas. Unless it is a super hot day, you can toss a lit match in diesel or kerosene, and chances are the match will burn a few seconds, then go out. You need the vaporization of the fuel to get the flames. That's what Savarin caused by slowly adding kerosene to hot metal with sparks.
All true, but kerosene's flash point is only around 150ºF. That's not much hotter than water from the hot tap. And on top of that, it's autoignition point is only around 425ºF! The cutting point on an EDM is going to be much higher than that. And it's true that ignition requires oxygen, but it still feels like tempting fate to use kerosene around an open spark, even totally flooded. Seems like all it takes is one mistake...

And a lot of automotive fuel pumps are submersed in the fuel tank and the fuel flows right over the commutator and brushes.
Also true, but there we're talking about an automotive electrical system. Much lower wattage than an EDM. On top of that, if you're getting sparks in your motor, it's destroying itself. Those sparks will erode the commutator and rotor just like they erode metal in the EDM.

exactly why I decided on distilled water for my EDM.......I can't be trusted! :oops:
(@savarin, it is not meant as a gloat or "I told you so", just as a example of a compromise/substitute for safety's sake).

Yes my EDM vise is rusty, I want to try a wax coating or something......
Interesting. So the EDM doesn't push enough wattage to crack the water into free hydrogen and oxygen? That would create a whole new set of flammability issues!

So as a question to all and sundry who actually have EDMs. What about standard cutting fluids like emulsified synthetics makes them less desirable here? Conductivity issues? Cost?
 

brino

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There were some comments above about removing swarf.
Here's a shot of the acid brush I use to remove swarf and apply cutting oil to the work area:
chip_brush.jpg

The milling cutter grabbed it, pulled it thru and spit it out the other side.
I am so glad it wasn't my fingers.

I still use it.....keeping it as a reminder......

-brino
 

brino

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Interesting. So the EDM doesn't push enough wattage to crack the water into free hydrogen and oxygen? That would create a whole new set of flammability issues!

So as a question to all and sundry who actually have EDMs. What about standard cutting fluids like emulsified synthetics makes them less desirable here? Conductivity issues? Cost?
Hi Hurley,
I want to respond with what I know, but this page looks like my soliloquy.
In order to keep this thread on topic, I'll respond here:
http://www.hobby-machinist.com/thre...hine-version-2-edmv2.49689/page-2#post-443894

-brino
 

RJSakowski

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Reading through the thread, saw a couple of posts about welding sparks pitting windshields on cars in the garage. This reminded me of a small welding project I did two or three summers ago. I always wear protective gear when cutting or welding -summer and winter. So took off a nice new fleece pullover, and put on my old leather welding jacket. Buttoned it up to the neck, doned the gloves and hood and went to work. About 10 minutes later I had welded the fixture up and took off the leather coat to put everything away. As I turned around, I noticed my nice new pull over fleece I had folded up and placed behind me on the ground, out of harms way, had turned into a small synthetic bonfire. The flames had burned a nice hole right thru the center of my garment, right down to the pavement. Somewhere along the line, welding sparks had somehow bounced into the fabric and ignited. I stamped the fire out. But holding up the pullover, could see nothing left except the arms, neck, and zipper, and a bunch of ragged, burnt and melted fabric around the edge of the garment, with avery large hole burned clean through the body.
It would have been worse had you been wearing it at the time!
 

mephits

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RJSakowski

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Also true, but there we're talking about an automotive electrical system. Much lower wattage than an EDM. On top of that, if you're getting sparks in your motor, it's destroying itself. Those sparks will erode the commutator and rotor just like they erode metal in the EDM.

Interesting. So the EDM doesn't push enough wattage to crack the water into free hydrogen and oxygen? That would create a whole new set of flammability issues!
Cost?
Re: the in-tank fuel pumps, my first encounter was with a Chevrolet Vega and I wondered about them at the time. As I recall, all brush type motors create sparks, regardless of size or power. If I recall correctly, the brushes weren't even enclosed to allow for gasoline cooling the motor. The saving grace is that the constant flow of gasoline cools the area so there is little possibility of vapor and there is no oxygen present. I don't recall if the pump sat in a sump so it couldn't ever be exposed to air.

Re: the EDM process in water probably does break water into hydrogen and oxygen. However you have fuel, oxygen, and ignition source in the immediate vicinity. They would spontaneously be combined to produce water vapor which would be condensed to water again.
 

kvt

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OK, RJ you are dating things, I use to have a Vega, There was a small sump area but not that big. That stupid plastic screen kept clogging up on mine, what was the use of the fuel filter when it could not get that far. Of course I would swear someone put something in my gas tank just to p___ me off. But at least it was not as bad a trying to put a fuel pump in the tank of a Ford Aerostar when it quite just after you filled it up. I would swear I smelled like gas for 2 days, on that road trip.
 

Kevin J

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There were some comments above about removing swarf.
Here's a shot of the acid brush I use to remove swarf and apply cutting oil to the work area:
View attachment 141751

The milling cutter grabbed it, pulled it thru and spit it out the other side.
I am so glad it wasn't my fingers.

I still use it.....keeping it as a reminder......

-brino

It looks like you can get a better grip on that brush now.

Kevin J
 

Mach89

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When turning on a lathe (especially close to the chuck) make sure you know which lever disengaged the carriage feed. I was turning a piece of 9" od aluminum and was almost to the end of my cut so I reached down and grabbed a lever to be ready. Turns out it was the cross slide lever. So I ended up running my tool into the chuck jaws before I even noticed I had the wrong one.

Long and short of it; pay attention to what you are doing at ALL times.
 

Mach89

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9e7a71d133117bc1a5573b20f9a9cff2.jpg
40d445239bdaecf8bbb24c26f8a50e47.jpg

Be careful when using a 4-1/2" angle grinder with a stiff wire brush wheel on it.
Last spring I was at work making the bearing adjustment nuts in the first pic and had to clean up the bur on the threads. I didn't really have a good way of doing it available, but I had a grinder.
Using that was my first mistake. Using that wheel was my second. I was knelt down on a pallet with one of them standing up between my knees. I was holding it with one hand and running the grinder with the other. I was trying to stay in line with the threads but I got twisted just enough for the wheel to grab and pull the grinder out of my hand. Of course, it went flopping around like a fish and went right across my knee (second pic). Needless to say, I found a different, albeit slower, way to do it. Using both hands is not always easy (sometimes impossible) depending on the work, but a good grip, and proper wheel can prevent a lot of damage. Looking back, I can see numerous mistakes I made doing that, and I'll always have this scar across my knee to remind me.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 

brino

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Be careful when using a 4-1/2" angle grinder with a stiff wire brush wheel on it.
Absolutely agreed!
I'd rank the knotted wire cup brush on my angle grinder second only to my chainsaw for most dangerous tools on the property.
Either will grab loose clothing and wrap it all around pulling you in.

The difference is the chain on the saw is further from the trigger and people have been trained not to hold what they are cutting with it.
With the grinder it seems like it should be controllable, but my experience has shown it is not!
You just need to catch a corner of the part your trying to clean and the tool is off in unexpected directions.

-brino
 

Dean Segovis

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How about one of those wheels for a 4.5" grinder that has CHAIN SAW TEETH on it!!!?? I was using one (reluctantly) on a job site in Hawaii on a decorative wood log. It had no guard on it. (stupid) It caught on a knot, jumped out of my hand, hit my right thigh about 2" below the "twig and berries", rotated several times thus wadding and shredding my pants around it's wheel-O-death, then hung there in the OFF position!!
Fortunately it had the "dead man" style trigger that turned off when released. I uncoiled the beast expecting to see mangled flesh and blood but only saw a circular grind mark in my leg that had not started to bleed yet. You know, that kind of wound that takes a few minutes to eventually ooze forth blood then slowly bleeds for 30 minutes. I was relieved but also slightly woozy at the thought of what MIGHT have happened. I could have ended up a transgender.

I removed the aforementioned wheel-O-death from the grinder and sent it flying Frisbee style into the sugar cane field never to be seen again.

First mistake was even using the thing!
Second, no guard in place.
Third, climbing cut with the cutting edge spinning TOWARDS ME!!!

Stupid mistakes.

Lucky me eh?! :)
 
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Bill Gruby

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My wife loved the you know what part on line two. She's still laughing.

"Billy G"
 

kvt

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Well I know that both will a 4.5 grinder and a chain saw hurt.
While in Alaska I was cutting a bunch of trees and for firewood and wind kicked up and caught a tree sent the thing flying back at me. even though you let off the trigger it still spins. Came down across my knee, A couple of little cuts in the paint leg, but when looking at the know you could see the slices from each tooth on the blade right down into the knew cap. Patched it up and went back to cutting.
using a 4.5 with the brush cup and caught the corner of the work, it was the old style with lock on trigger, had not guard on it and kicked right back into my stomach wrapped my shirt around it but left a nice little abrasion scar where the brush poked through the cloth nice thing was it was a cheep one with out much power, and unplugged is self. or it could have been worse.
I have been told I am just a disaster waiting to happen, and at times it seem like it.
 

Downunder Bob

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Nope, just another Marine crew chief doing his job, getting as many as he can out of harms way and hopefully home safe. Sometimes it worked, sometimes not. but I did my best and that's all the Marine Corps expected. Once in a while I do miss those days, but it is an extremely fleeting thought. LOL

"Billy G"
I disagree bill, All men and women who have served, or are serving, particularly volunteers are heroes to my mind. Nothing less than respect is good enough.
 

Downunder Bob

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Like many things, they are a means of risk management. It's true there could be adverse side effects (as with most any medical treatment), and you should not take them indiscriminately. But in our line of work (or hobby) there are definite risks of infections that are non issues if we are current on our shots. It is a personal decision, of course, but the generally accepted reasoning is that the risk of side effects is low in comparison to the risk of serious consequences resulting from an infection that would have been prevented by the shot. I've been taking them since I went into this line of work, every 10 years I believe.
Throughout my working life a s a marine engineer we were required to have shots for everything. I've now been retired for a while and recently when turning 70 I saw my doctor for a major checkup and asked about an updated tetanus shot, he said at my age and considering how many I've had, that I'm covered for life. Hope so.
 

Downunder Bob

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There were some comments above about removing swarf.
Here's a shot of the acid brush I use to remove swarf and apply cutting oil to the work area:
View attachment 141751

The milling cutter grabbed it, pulled it thru and spit it out the other side.
I am so glad it wasn't my fingers.

I still use it.....keeping it as a reminder......

-brino
I was told as an apprentice to never use a brush any where near a running machine, If you cant use flood coolant use a spray can or a squirt gun, and that was 55 years ago. And to use a proper swarf hook to remove swarf.
 

Downunder Bob

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I was on a job a couple of summers ago building a new hospital. Walked back out to the vehicle. Didn't need a key. Right rear passenger window was in tiny little pieces (safety glass). Never really figured it out. They were doing some mowing around the area, but it was record hot that day, and my vehicle is black. I looked inside thoroughly for a foreign object from the mowers.....kind of hoping it was them so I could make someone pay for the glass, but never found anything. Guess it could have bounced off. Watch where you park if there is a contract mowing crew around!

Funny thing was, even the dealer was not able to get the correct tint. It has (now has one) really dark passenger glass. Factory says no, it doesn't. I had to put the wrong glass in. I started looking, and about 80% of the ones I see on the road HAVE the near black glass. Others have a sort of goldish tint. I went aftermarket and got as dark as I could.......still burns me. I drove around with a Plexiglass window for 2 months looking and trying to get the right one. Now I see them on ebay all the time. I just hate to buy one twice. If I do, I'll try to sell this wrong one to somebody.
That safety glass can do that, Explode in the heat. A few years ago we bought a new table for the outdoor BBQ area. The table was glass top made out of auto type safety glass. About a month later, came home and found the glass shattered all over the place. Took a photo and a bag of the glass pieces back to the shop. they replaced the table, no questions , but when it happened a month later they said they would replace it but not with a glass top, so we've had a timber topped table ever since. On both occasions it had been a very hot day around 42-43c Shortly after that they stopped selling glass top tables for outdoor use.
 

Wreck™Wreck

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Just remembered doing this, , using the carriage feed to push the tailstock along the ways setting up for a long part, failed to pay attention and pushed it right off he end into the chip pan, this is not a recommended practice
 

Downunder Bob

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Just remembered doing this, , using the carriage feed to push the tailstock along the ways setting up for a long part, failed to pay attention and pushed it right off he end into the chip pan, this is not a recommended practice

Just a s well it didn't land on the concrte floor might hav edamamged bothe floor and the tailstock.

My lathe has a peg, screwed into the base under the ways, that prevents the tailstock from falling of the end. I guess it would shear the drive pin off in the feed shaft, or break something else. The peg can be removed if needed.

However I don't see myself using that method as my lathe is very short only 16" between centers, and the tailstock moves quite easily. How about installing a limit switch to stop it happening again, or a linkage to disengage the feed, there is always more than one way to solve these problems.
 
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