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Reader Says Mythbusters Missed on Hammer Strikes
comments (96) August 4th, 2009 in blogs
We received a lot of letters about the dangers of hitting hardened steel with a steel hammer, sparked by a photo in the Fundamentals department in issue 205. After the author of that article, Steve Latta, copped to doing a no-no in the Letters column in issue 206, we ran a clarification in our most recent issue, citing an episode by the Mythbusters that supposedly debunked the myth of hammer-on-hammer dangers.
But the debate goes on. Robert Geers, a reader from Cedar Key, Florida, claims the Mythbusters are all wet, and says, in fact, that the dangers are real.
Hammers Striking
I was one of those who wrote in regarding striking the faces of hardened hammers together, so when I saw the "Clarifications" note I went to the site and searched out their tests. Or should write "Tests" in quotes, because they were not logical, and when they said "The hammers began to chip" but still declared it to be a myth, they missed the whole point.
Striking two hammer faces together, especially if swinging one at the other, places the likely "Chip" on a plane with the eyes. Only a small chip is necessary to do real eye damage, and having seen any number of chipped and abused nail (carpenters) hammers I KNOW the chips had to go somewhere, and they did not fall off while the hammer was in storage.
As a Woodshop teacher of 34 years, I know what I'm talking about on this subject. A hardened hammer, which all nail driving hammers are, WILL chip if abused by striking a hardened steel surface, maybe not the first time, but it will chip, and the resulting chips are dangerous.
I have no "Dog in this fight", except the long standing desire to keep my students safe. And your statement of "gentle taps" is like being a little bit pregnant. The "MISS-Busters are , in my opinion, quite wrong on this.
But as my students would sometimes say, "Whatever".
posted in: blogs, tool, hammer, miter gauge, latta, technique, strikes, mythbusters
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Comments (96)
blood was spurting out 1/2 inch below the tip of my chin
where a 25 caliber size piece of razor sharp shrapnel entered
my neck.The Urgent Care facility I was driven to said it was to deep in my neck for them to attempt and extraction. I would have to go to a surgeon that specializes in ear,nose and throat surgeries.
So here I am with a severely bruised neck down to my chest and getting worse by the day.So I would have to disagree with MythBusters if they found no danger in the practice of hitting hardened steel to hardened steel.I knew it was a stupid thing to do as I did it.but I did it anyway.I thought the odds of something terrible happening were small but it happened and now I have to deal with the consequences.
Thank you for taking the time to read this I hope it may save somebody from the pain I am going through.
Patrick Burnworth
Patricyde@hotmail.com
Posted: 3:34 pm on May 24th
Ian
Posted: 10:53 am on October 18th
As is pointed out time and time again, why take the chance by testing your own hammer by banging it? Here's a recent event where steel shattered, and even certified safety glasses weren't enough to protect his eye:
http://machinedesign.com/article/inadequate-safety-glasses-no-miner-factor-in-injury-0810
Posted: 8:15 pm on August 24th
PS The Hardness of a tool is generally set in the final "strike" in the factory, that creates it's final shape. This is why drop-forged hammers are superior, But, this is more of the story.
Posted: 1:40 pm on August 24th
Just tmy two cents.
Posted: 9:17 pm on August 23rd
Posted: 9:07 pm on August 19th
Posted: 1:47 am on August 19th
I have problems agreeing with the myth busters. I have been working with hand tools (including hammers, chisels, and punches) for over 40 years and have had several hardened items chip or fly apart when being struck.I worked in a heavy equipment repair facility and we commonly used two 16 pound sledge hammers to free frozen gears or items pressed together with up to 200 tons of pressure. One hammer was held on the frozen part and then struck with the second hammer. Not only have i seen chips fly out from the hardened surfaces of either hammer, but more importantly numerous hammer handles came loose due to the hole in the hammer head being deformed when struck by another hammer.
Posted: 11:06 pm on August 18th
Posted: 6:10 pm on August 17th
Posted: 6:05 pm on August 14th
Posted: 11:55 am on August 14th
Posted: 1:57 am on August 14th
Posted: 12:44 am on August 14th
On the other hand, I chip stone. I can and have chipped stone all day and know just where each chip will come from and where it will go. The chief lesson learned is that chips are predictable. Any brittle material will chip and the geometry of the strike and striking surfaces, the relative hardness and toughness of the hammer and the object being struck all enter into the result. You would not for instance try to chip glass with a glass impactor.
If you try driving the claws of one hammer under a nail using a another hammer, the plane of the strike interface is going to run through your body, possibly even your head. Since the hammer faces are likely to be nearly equal in the important physical traits (like two pieces of glass or obsidian), either piece may chip. Since the primary degrees of freedom of motion for resulting chip motions are going cluster around the plane between the impacting surfaces; the motion of chips is going to be within a few degrees of that plain. If you can see that point, that's bad. If someone else's body can be intersected by that plane, that's bad. If a surface is present near the blow and and could serve to cause ricochets, that is not good either.
Adequate safety precautions are fairly simple. First, never, ever strike two objects of similar composition and physical character together (well lead or copper will probably be OK, but even brass will sometimes crack and chip). Second, wear safety gear. Third, have others clear out of the potential discharge path of resulting chips. Fourth, a backstop should be a material a chip will embed in rather than bounce off. So peen on a piece of plywood on the workbench, NOT on the cast iron saw table.
JDougherty
Posted: 8:19 pm on August 13th
Posted: 7:40 pm on August 13th
I too have been hit in the cheek by a chip coming off a claw hammer being struck by another claw hammer trying to get purchase on a nail. No damage, but a good warning.
Thanks, Dulcimers (Len Dorsett) for the explanation. Now I know why my splitting wedge, and cold chisels behave the way they do. I have always ground off the fractured bits, but it was to keep them from shredding my gloves. Now I have a better reason.
Posted: 6:47 pm on August 13th
Posted: 6:04 pm on August 13th
They said a bullet fired straight into the air couldn't hurt anybody, yet the same show interviewd a surgeon that has treated at least one such case.
Will there be chips when two hardened surfaces are struck together? Oh Hell yes! I still have the chunk of chisel in my lower abdomen from striking a hardend bearing race with the chisel with out heating the race to soften it first. There is always the possiblity of chips even when one surface is softer material. When it comes to safety, think 3 or 4 times first.
Posted: 10:52 am on August 13th
Posted: 11:30 pm on August 12th
Posted: 9:22 pm on August 12th
Posted: 9:22 pm on August 12th
In my working life I have come to a simple conclusion. When one hard object hits another hard object, there is ALWAYS a chance for chips to fly. I don't care if an engineer tells me its impossible, I have seen to many impossible things happen. Luckily I have never injured myself, but I have seen some one eyed people that are shy one eye because of something hard flying.
This leads me to the inevitable conclusion that chips can and do fly from hardened objects when hit by another hardened object. Is this going to keep me from doing it? Nope! Sometimes it is just the best way to do something. But being a smart Redneck, I am sure going to be careful when I do it. I use eye protection, leather gloves, heavy pants and shirt.
Look at it this way, the new sawstop table saws can stop a saw blade without damaging a hot dog. But does that mean you are going to stick your hand into it to test it? I won't. I am still going to practice good safety. Doesn't matter if its two hammers, or a table saw. Remember, all it takes is one error, and all your friends will be calling you lefty, or patch, or one eye, or something equally moronic.
About the original myth, remember Murphy's law. Remember the crash of United Airlines Flight 232 at Souix City. That was caused by a microscopic bubble in a rotor. If someone can think of an accident, I can guarantee that eventually it will happen. Might not happen to you, but it will happen to someone.
Be safe!
Posted: 8:16 pm on August 12th
Posted: 7:20 pm on August 12th
Sincerely,
Robert H. Galloway
Posted: 7:04 pm on August 12th
When a cow pook was asked "How close can you get to a rattle snake without getting bit?" He answered " Don't know how close but know I'll stay as far away from it as I can get!" Same goes for hitting two hardened metals, or hammers together! Make it a hard and fast rule---don't.
Posted: 6:32 pm on August 12th
There are a lot of valid comments about chips flying off the faces of hammers (and other heat-treated tools) in this string of postings. The technical reason for this is that high impact can cause some of the steel in the tool to transform to "martensite", which is the hardest and most brittle form of steel. When you heat treat a tool to make it hard, you first quench it from an elevated temperature to transform all (or most) of the steel to martensite. In that condition it is hard, but it is too brittle to be useful. The next step is to heat the tool to a moderately high temperature to transform the martensite into something called "tempered martensite". The higher the tempering temperature, the lower the hardness and the less brittle the steel. OK, that's the end of the lecture - but I'll be happy to answer questions about steel heat treatment from interested folks.
The key is that hitting a hammer can transform some of the head to brittle martensite, and that is where the danger lies. The next time you hit that spot a chip can break off - as was well attested in precious comments. Probably the most common occurrence is with wood-splitting wedges. They get pounded hard all the time, and they often produce flying chips. Always check your wedge heads before use and grind off any split or cracked areas.
Having said all that, I really doubt that hitting a ball=peen hammer to dimple a miter bar is going to cause a flying chip UNLESS the hammer head already has some martensite from previous abuse. It is just not a hard enough blow. Just be sure to check your hammer heads frequently for chipping and cracking and grind off the chipped area or get a new hammer.
Len Dorsett
Posted: 6:19 pm on August 12th
Posted: 5:45 pm on August 12th
Now, I would like to add my comments to the 'Hammer Strike' debate.
Whwn I was just going-into-teenager my father worked for a local hauling company, driving large trucks. The money wasn't all that great and so he took advantage of any opportunity to scrounge things that would have been wasted. One of the things he brought home was rough 2x6 and 2x8 lumber that had braced new vehicles in the railroad cars to prevent their moving about. Many of the boards were strapped at the ends to others, held in by spikes. After getting them home it was a job removing the metal strapping & the spikes. One of the ways to remove the spikes was to drive the claws of a hammer under the head of the spikes to get that initial purchase.
I was doing this one day using 2 clawhammers. striking them face to face, when I recieved a rather severe eye injury. I though at first that an end of the strap had flicked up & hit me, but after waiting 3 days in the hallways of the local hospital after x-rays, I was sent to the University of Alberta Hospital where more expert medical was available.
They saw that there was a chip of metal embedded in my retina, and tried to do something about removing it, but the pressure in the injured eye was so great they couldn't penetrate into the eye itself. Considering that this was in the fall of 1957, I was probably lucky they didn't remove the eye.
So I was left with a chunk of steel embedded in my retina for many years. In about 1990 my GP wanted an x-ray of my sinuses because I had several bouts of an infection. When he saw the bright white spot on the x-ray he immediately wanted to see me. After explaining what and why it was, he ordered some sophistocated tests, as the iron leaching into the interior fluid would eventually destroy the retina's capability. Five years later the same tests revealed that there was a noticeable deterioration in the retina's capability, so he sent me to a eye specialist to arrange the surgery. At the same time, that eye was devloping a cataract, so another surgeon joined the fray & both were done at the same time.
The metal chunk had embedded itself in the retina, severing the nerve to about %40 of my vision. The chunk broke up into several particles as she tried to grab it, so she ended up suctioning out a lot of the fluid to get it all, more than half of it. I then had the curious sensation of watching my eye refill itself over about 2 months or so. Only after the level reached above the pupil could I see objects with any clarity.
I still have that chunk of hammer. It was about 0.5mm by 0.3mm by about 0.1mm thick. It had gone completely through the lower white of my eye, through all the gel/fluid in the interior and had lodged itself in the retina at the back of the eye, severing a lot of nerves. It missed the main optic nerve 'bundle' in that eye by about 5mm.
I have always wondered what it's actual velocity was.
dsparks
Posted: 5:26 pm on August 12th
The danger arises from the physics of the strike. The least amount of danger (since we're talking about moderate blows) occurs when the two faces are perfectly flat and strike each other as perfectly parallel hammer faces.
The rub is perfectly flat and perfectly parallel. What hammer face is perfectly flat (let alone two)? And as we know (think floor loading calculations or pushing a chisel through), the force is multiplied as the contact area is reduced. One hammer slightly askew is all it takes to multiply the moderate striking force into a great amount of force at the place of contact.
My verdict? Don't risk it.
Posted: 3:58 pm on August 12th
John Watters - been there and seen it
Posted: 3:48 pm on August 12th
Posted: 3:39 pm on August 12th
Posted: 3:17 pm on August 12th
On this web page, http://www.finewoodworking.com/item/17562/reader-says-mythbusters-missed-on-hammer-strikes , you feature a photo of some misbegotten soul striking the upper surface of a miter gauge bar.
That surface must NOT be abused, lest it project above the table surface or bow the bar out-of-flat. The subject concerns improving fit in the slide, which requires work on the SIDES of the miter bar.
You've shaken my faith with this error.
Posted: 1:45 pm on August 12th
The trick is always to use a hammer against a softer material. In this case, a hammer and center punch would have been appropriate. Needless to say, using any hammer or similarly violent tool without eye protection is foolhardy, no matter how light the blows. Stand beside the tiger long enough, and he'll eventually invite you to lunch...
It is not safe to claim that "I was only going to hit it a few times, and not with much force." Hardened steel against hardened steel is dangerous in any striking situation.
Striking purpose-built steel tools together is an investment in faith in the manufacturer, because all steels are not equal, and the differences are not detectable to the unaided eye. Tool manufacturers operate within strict tolerances for metal composition, strength, hardness, grain size and orientation, etc. so as to ensure that striking surfaces are compatible with one another among purpose-designed tools. For example, a center punch may have its tip tempered to extreme hardness, but feature softer steel at its striking surface. Similarly so for wood chisels, plane blades, etc.
If the user has so little sense as to "abuse the system", the tiger heads home for lunch.
Cheap hammers nearly always come from countries and manufacturers who profit from "looks like" tools aimed at amateurs who don't know the necessary details. For myself, I never purchase a steel-head hammer not manufactured in the U.S., England, or Germany by a reputable, time-proven manufacturer.
Incidentally, there are two rows of center punch marks down each side of my miter square's bar, which I struck and then filed to perfect fit over 25 years ago. The effort is lasting, and well worth the time to perform properly. My daily user is a newer Incra with screwed buttons for slide clearance adjustment.
Posted: 1:27 pm on August 12th
Looking back as to when the chip in my knee first occurred was probably in the early sixties when I was in metal shop in school and hammering metal on an anvil. I recall the hammer had chipped and had hit my knee. I didn't realize the blood on my knee indicated the chip had embedded itself in my knee.
There was probably nothing I could have done to prevent the injury. But to say this doesn't ever happen is folly. I can only imagine what would nave been the outcome if the chip had embedded itself in my eye.
Posted: 12:54 pm on August 12th
I agree with Beckum... use brass.
Posted: 12:47 pm on August 12th
Posted: 12:38 pm on August 12th
Posted: 12:35 pm on August 12th
A lesson I took to heart 60 + years ago when a friend's older brother hit two, what I learned later were framing hammers, together, He sported an inverted teardrop for the pupil in his left eye. A piece fractured off and cut the Irus. Fortunately it didn't blind him. So even if rare why temp fate. Why not stand beneath a tree during a lightening storm if strikes are really rare? Because of the 'image' I, to this day, do not strike hardened surface on purpose. Being a retired mechanical engineer suggests not to. I keep two ball peen hammers for striking metal.
Posted: 12:23 pm on August 12th
Hope your hairsplitting and griping goes well; I think I'm headed back to the shop.
Posted: 12:18 pm on August 12th
Why not use a wood mallet on the hard hammer if you need to make a light tap?
Posted: 12:01 pm on August 12th
Just don't do it!
Posted: 11:28 am on August 12th
Posted: 11:25 am on August 12th
This reminds me a lot of the letters we get each time we run a photo of someone grinding on the side of the wheel. Grinding should be done with a light touch, and there just isn't any danger of the wheel exploding as some warn. Yet the letters pour in, saying, "I was always taught..."
I went to tech school for high school and worked in machine shops, and saw people use the side of the wheel regularly and safely, but with a light touch, of course. The edge of the wheel is where you should do most of your grinding, but there are times when the flat side comes in handy.
Posted: 10:58 am on August 12th
Posted: 10:54 am on August 12th
Posted: 10:51 am on August 12th
Posted: 10:34 am on August 12th
I am a shop teacher of 31 years. Fracturing hammers is no myth. I knew better; but used two hammers in conjunction with each other to straighten a bent truck rim that came in contact with a curve. They worked fine to fix the rim but I have a chunk of metal buried in my left thigh to prove hammer heads due in deed fracture when they impact each other. I was fortunate it did not strike an artery or my eyes. Needless to say,I will never try this again.
Posted: 10:24 am on August 12th
Posted: 10:15 am on August 12th
Second, another poster said that a brick chisel is hardened steel and no one was ever hurt by a shattering brick chisel. True, but as far as I know, only the edge of the brick chisel is hardened--the striking surface is not. Even so, chisels that have "mushroomed" have been know to have pieces fly off when struck. I guess the moral of the story is to at least always wear safety glasses.
Posted: 10:12 am on August 12th
with this experience I have not only seen this chipping happen when I was young I learned abouy this the hard way.
These hardened surfaces are brittle and if they are impacted at the right angle they will chip. I have seen one shatter, trust me on this is is no fun to see that happen.
Seth ( the old plumber)
Posted: 9:52 am on August 12th
I consider whatever results I get from them as additional anecdotal evidence, not a real study.
Their program is entertainment first, information obtained from them is just what you see. And it is not rigorous in considering real world, long term use, covering all options availabe, or a hardcore scientific study.
Enjoy their program, but just consider it entertainment, not more, not less. And yes, I enjoy seeing their stuff too, just like I enjoy the Dirty Jobs show.
Posted: 9:48 am on August 12th
Posted: 9:45 am on August 12th
Explode with lethal force? To be fair, it didn't truly explode but I'd say that had that chunk hit someone in just the right spot it certainly could have been lethal. I still work in the contracting / woodworking biz and I never, ever hit hammers together.
Posted: 9:25 am on August 12th
Posted: 9:21 am on August 12th
Posted: 8:55 am on August 12th
Posted: 8:50 am on August 12th
Posted: 8:41 am on August 12th
Also saw the MythBusters episode and that was a poor experiment and test. The heat treating process that they used near the end of the show was uncontrolled/sloppy and resulted in the wrong microstructure to cause chipping -- I didn't need to see the end to know that hammers would bend rather than chip. During the test, the heating temperature was too low (some people recommend a magnet to test for proper heat, but that is wrong as well because the nonmagnetic point for steel is about 300 degrees too cold to quench); they walked about 10 yards before they quenched the hammer so they lost even more temperature; they quenched it in oil (probably should have been in a water blast for the hammer steel chemistry); I am assuming that they believed that oil would add some carbon (another wive's tale); and finally, even if they did the heating and quenching right (which they didn't), they removed the hammer from the oil before it would have reached a low enough temperature to form martensite (harden). All in all, a failure.
Posted: 8:41 am on August 12th
Since we can't afford $20,000 hammers, ours have some faults. So how can hitting together any two forged, hardened, tempered things ever be safe? It can't. That is why only the cutting edges of cold chisels and pin drifts and other striking tools are hardened and tempered. The haft (the head or top) of the struck tool is left soft to deform (mushroom) well below the cracking threshold of the striking tool.
The man shown striking a peening hammer is just using the wrong tools. He can use the flat face of a forged hammer to strike a round peening dolly (e.g., a Dagger CP560) or a convex dowel drift (either of which, of course, have soft hafts). For most of us, the best (cheapest) solution is to use our brass or bronze hammers (for peening, use an 18 to 24 oz head) to strike the ball peen hammer. Both the brass and peen hammers should be stored WITH your struck tools.
By the way, peening is a fitting operation, so the miter gauge must be peened while in the grove. The commentator who thinks this a problem is wrong.
Remember, using a bronze or brass hammer means that you won't damage struck tools, you won't create sparks and you won't have to worry about high-velocity steel shrapnel. Afterall, it's supposed to be a shop, not a war zone.
Posted: 8:36 am on August 12th
A b-b sized pellet from the hammer head flew across the room and hit another brother in the eye. The impact knocked the second brother off his feet and his impact with the wall broke through the plaster board.
Result: emergency surgery and loss of sight in that eye.
Posted: 8:34 am on August 12th
For those of you that think it is safe, I put you in the category of the people who drink and drive. You may be lucky and never get caught or have an accident, but many are not and pay the price.
By the way, I am a shop teacher. I teach my students that the myth busters is a good show not to watch. I used to watch it until the hammer episode, then I realized these guys are NOT experienced scientists, they are only show people trying to make a buck.
Posted: 8:32 am on August 12th
Aside from all this, you'd have to hit the two hammers together pretty hard to create a chip and likely it would not occur on a single blow but after a fair number of strikes. Me? I'd just settle for the proper tool. A steel centre punch. But still wear those safety glasses.
Posted: 8:14 am on August 12th
HOWEVER!! Let me also say that a sharp hard steel/hard steel blow with heavy arm strength force will indeed produce shrapnel that will penetrate human tissue with the greatest of ease. I learned this as a young man the hard way--resulting in having a thumbnail sized divet from a hammer face surgically removed from my forearm--ruined my good Plumb hammer but the Bluegrass survived.
Posted: 8:10 am on August 12th
If a person needs to do this a piece mild steel or brass needs to be used. The risk isn't worth it.
Posted: 8:05 am on August 12th
Posted: 7:11 am on August 12th
It doesn't take a genius to realize that hitting one hammer head with another is dangerous. As always, common sense should prevail.
Posted: 7:02 am on August 12th
After 36 years of working on and around drilling rigs, I've seen all types of hammers...from 16 oz. claw hammers to 16 lb. sledge hammers used and abused in every way imaginable. I've never even seen one chip, much less explode.
Besides, there are few actions in a woodworking shop that someone will not consider unsafe. Practicing common sense safety is a good thing but seeing or imagining danger around every corner becomes a bit jaded after a while.
Posted: 5:30 am on August 12th
After 36 years of working on and around drilling rigs, I've seen all types of hammers...from 16 oz. claw hammers to 16 lb. sledge hammers used and abused in every way imaginable. I've never even seen one chip, much less explode.
Besides, there are few actions in a woodworking shop that someone will not consider unsafe. Practicing common sense safety is a good thing but seeing or imagining danger around every corner becomes a bit jaded after a while.
Posted: 5:30 am on August 12th
After 36 years of working on and around drilling rigs, I've seen all types of hammers...from 16 oz. claw hammers to 16 lb. sledge hammers used and abused in every way imaginable. I've never even seen one chip, much less explode.
Besides, there are few actions in a woodworking shop that someone will not consider unsafe. Practicing common sense safety is a good thing but seeing or imagining danger around every corner becomes a bit jaded after a while.
Posted: 5:30 am on August 12th
A hydraulic press (iirc, 250T) had a cube of hardened steel left on top of a hardened steel tool, you guessed it, the top tool came down on it. The cube would have been a couple of inches high, the tool clearance about 1.5mm... It "shattered explosively" in my opinion, leaving him with a hole in his throat - about the size of a U.K. 5p piece, requiring surgery. He died from a completely different accident involving alcohol and a car (which he wasn't driving).
ANY hardened steel tool should be treated with respect, as you can drop them on toes, and cause injuries - that's not travelling too fast either...
Posted: 5:29 am on August 12th
I have the X-rays taken before both MRI's that confirm the piece of the claw hammer head is still in my arm.
Case hardened claw hammer heads are very wear resistant against relatively soft nails. BUT the process leaves a brittel layer that is prone to fracture by impact with a through harded surface.
Posted: 5:28 am on August 12th
Posted: 5:20 am on August 12th
Posted: 4:27 am on August 12th
Posted: 3:46 am on August 12th
"Explode" like a bomb? Maybe or maybe not. Knock off a flying steel projectile capable of inflicting injury and pain? Most certainly!
Posted: 3:36 am on August 12th
Posted: 3:27 am on August 12th
Posted: 2:39 am on August 12th
I wouldn't be peening on the saw table either, but I would guess that probably he is just taping the peening hammer, not swinging at it! Probably not hard enough to shatter it or chip it! if he has to swing the hammer to peen, he is using the wrong tool!!!
Posted: 9:57 pm on August 11th
Posted: 7:57 pm on August 11th
Posted: 7:29 pm on August 11th
As to the original image, I cringed twice when I saw it. First, the man is pounding on his saw table! This is not a workbench; this is a finely tuned (hopefully) woodworking instrument. Second, as your readers pointed out, hammer faces should never be struck together. While it is doubtful that an explosion would occur, chips can fly at explosive speeds, and pierce body parts.
Finally, instead of using a ball peen hammer, for the the process of removing play from the miter gauge (I assume that is what he is doing in the picture) I suggest using one hammer, a center punch and a solid flat work bench.
Striking the side of the bar with the punch will dimple it and gradually tighten the bar in the slot. Go slowly and check the play until satisfied it is snug enough.
Posted: 7:13 pm on August 11th
The picture you see above is okay to do. I have been doing this for years with nothing bad happening. People come right next to me and watch, nothing happens. The mythbusters show was absolutely correct in what they said and the test methodologies. But the one fact the no one has ever thought of, except me, is why isn't anyone asking the hammer manufacturers for there opinion.
You know what they would say: Don't stike two hammer faces together. Why, cuz it is there for liability reasons. THe chance of that happening is slim to none.
lates
Posted: 6:38 pm on August 11th
Posted: 6:20 pm on August 11th
I and several other friends have had the same experience over the years. Mine was in my shoulder with the metal piece buried 1/4" below the skin. Glad it wasn't my eye.
This happens often enough to deserve the rules that GilbertAC posted above.
Posted: 5:42 pm on August 11th
Posted: 5:20 pm on August 11th
When I was sixteen I was making a jig for my dads tablesaw. I was using a piece of cold rolled steel to go in the guide slot. Using a large ball peen hammer to strike a small ball peen hammer to ding the steel bar to fit the guide slot better. The small hammer failed. One piece hit and penetrated a full one gallon paint can. A second piece went through a window. The rest of the hammer face landed at my feet. The peen end was still attached to the handle. Since the paint can and the window were about 135 degrees apart, from where I was working, I think this qualifies as an explosion. I later found out that the hammer that failed had been my grand father's. It was estimated to be about eighty years old and had seen a lot of use.
I now have two rules about striking one hammer face with another. 1. DO NOT EVER DO IT. 2. When in doubt see rule one.
Posted: 3:02 pm on August 11th
Why do you think the striking end of all steel chisels, punches, etc. are not hardened? Even then if the end gets mushroomed over too far it can make pieces fly.
Hey you! Put your safety glasses on! You'll see longer.
Posted: 1:12 pm on August 11th
I did not hit the face square and a chip flew off and severed an artery in my arm. Luckily it didn't hit my eye or an artery in my neck.
The whole face of the hammer had fine cracks after that and was not used again. I think another blow and the whole head would have shattered.
Posted: 12:59 pm on August 11th
Posted: 12:26 pm on August 11th
Posted: 11:59 am on August 11th
Cheers,
Ed
Posted: 1:53 pm on August 10th
While working in a coal mine in PA in 1975 my boss was trying to break a flight chain. He place the peen of a hammer on one of the pins and smacked it with another hammer.
I felt a jerk in my arm and saw a hole in my shirt. When I got to the hospital I was told that the fragment was embedded too deep to remove and that I would be OK if it were left in.
Never had any trouble with it, but to this day I'll NEVER hit a hammer with a hammer.
Posted: 10:14 pm on August 5th
That simply won't happen.
It may chip, and they noted this in the episode. IIRC, they even stated that the chips could be dangerous. But it's not going to explode.
Really, listen to what they are testing, not what you think they are testing.
Posted: 9:02 am on August 5th
Posted: 12:26 am on August 5th
I do agree with what Myth Busters are saying, in the context it is said. The odds of a hardened hammer face shattering another hardened hammer face and a chunk of it being able to impact with lethal force is pretty slim.
There is also a lot to be said about the text of this article. It will eventually shoot off chips that can cause injury and if that injury is to an eye, you'll have a good chance of becoming a eye patch wearer. And unless you're a pirate, it isn't a good look.
Posted: 11:29 pm on August 4th
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