Mason254 216 posts Report post Posted November 8, 2019 Absolutely puzzling! I've seen many holes in coins but none as this! Please look closely before just say O it is just coin someone felt like they needed to drill a hole in metal protruding from around the hole doesn't indicate that?? Share this post Link to post Share on other sites
Just Bob 4,289 posts Report post Posted November 8, 2019 As someone who has drilled many holes in metal, I can attest to the fact that "metal protruding from around the hole" is a common occurrence. It is not an error; it is damage. 1 CRAWTOMATIC reacted to this Share this post Link to post Share on other sites
Greenstang 1,146 posts Report post Posted November 8, 2019 I agree It has to be intentional damage. How else would it get there? It certainly wasn't on the planchet before the coin was struck. Share this post Link to post Share on other sites
CRAWTOMATIC 391 posts Report post Posted November 8, 2019 Science! This presents a good opportunity for learning. There are 6 simple machines: the inclined plane, lever, wedge, wheel and axle, pulley, and screw. (Though personally I feel the screw should not be included in the list as it's just an inclined plane wrapped around a rod - so it's repetitive to be mentioned.) There are many types of drills and most are considered complex machines because they combine two or more simple machines to function. A drill does not push the material through the medium, it extracts the material. A common drill bit has an inverted inclined plane sunk into a rod. This inverted inclined plane serves as a channel so that when it enters the medium and displaces material that displaced material travels up the channel and is deposited at the top of the shank. Sawdust, metal shavings, etc... So, to echo JustBob, yes, metal protruding from the entry point would be expected as the result of a drill. Share this post Link to post Share on other sites
Conder101 8,489 posts Report post Posted November 8, 2019 15 minutes ago, CRAWTOMATIC said: (Though personally I feel the screw should not be included in the list as it's just an inclined plane wrapped around a rod - so it's repetitive to be mentioned.) You can actually take it down to just 2 simple machines, the inclined plane and the lever. As you mention the screw is just an inclined plane wrapped around a post, a wedge is just two inclined planes back to back. A wheel and axle is an infinite lever with the fulcrum at the center and the end of the lever not stopped by the ground so one end goes "down" and the other up continuously. A pulley is just a wheel and axle with a rope running over it. As you pull the rope the infinite lever goes down on one side and up on the other and the rope goes with it. 1 CRAWTOMATIC reacted to this Share this post Link to post Share on other sites
CRAWTOMATIC 391 posts Report post Posted November 8, 2019 1 hour ago, Conder101 said: You can actually take it down to just 2 simple machines, the inclined plane and the lever. As you mention the screw is just an inclined plane wrapped around a post, a wedge is just two inclined planes back to back. A wheel and axle is an infinite lever with the fulcrum at the center and the end of the lever not stopped by the ground so one end goes "down" and the other up continuously. A pulley is just a wheel and axle with a rope running over it. As you pull the rope the infinite lever goes down on one side and up on the other and the rope goes with it. Right?? I mean, I'm not the one defining the list of simple machines but I'm with ya. Somebody else long ago decided 6 was the magic number so I'm just deferring to history. However, I believe it has to do with a balanced mathematical equation moreso than the design. Share this post Link to post Share on other sites
kbbpll 283 posts Report post Posted November 9, 2019 And here I am, thinking an inclined plane and a lever are basically the same machine too. Both reduce force at the expense of work. OP, your coin just has a hole drilled in it. What else did you think it is? Share this post Link to post Share on other sites
Mason254 216 posts Report post Posted November 9, 2019 I have literally drilled a hole in 5 totally worn Jefferson nickels with the same diameter with alternate speeds not one has metal protruding out nor around the edges outside furthermore all metals we expelled from the top and also not enough heat was created during the process I drilled them in a vise open end I drilled them on a flat surface every way I could think of and not 1 has the same results as the one I've posted so I'll set it aside and continue educating myself in numismatics Share this post Link to post Share on other sites
kbbpll 283 posts Report post Posted November 9, 2019 Well, in my experience that's just how intentionally holed coins look, but experiment away. 1 Mason254 reacted to this Share this post Link to post Share on other sites
VKurtB 690 posts Report post Posted November 13, 2019 On 11/9/2019 at 10:43 AM, Mason254 said: I'll set it aside and continue educating myself in numismatics Please, please do so. With some urgency, please. Share this post Link to post Share on other sites
