Straightening a bent coin

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I have a 1918 cent from the Netherlands. It is in vf condition but it is slightly bent or warped. I was thinking about wrapping it a thin cloth and putting in a vise or under something very heavy to straighten it out.

Do you think it might work? The coin is only valued around $2.00 so I think it might be worth a try.
The best way to try that would be under a hydraulic press, with the coin placed between aluminium or plastic sheets (3-4mm thick).

Tony
World coins by date and mint place, 1850-2000
I tried several times, it will not be good never. The bent material is stretched and if it straightens it does not go back again. Try a cheap coin.
Depends on how big is the bent. I have some success with the slightly bent coins using a special tool, Parallel Pliers with Nylon Jaws - your local hardware store should have it and it looks like this:

If not, than the regular (non-parallel) pliers with nylon jaws may be available in your craft store (jewelry making section). Don't try to straighten the coin in one move - but instead apply little pressure, turn the coin, press again, etc.
But if the bent is significant - Blasi is absolutely right - than the metal is stretched and you can do next to nothing...
There is a time for everything - Il y a un temps pour tout - Всему есть свое время - Для всього свій час, і година своя кожній справі під небом
I kind of disagree about the stretching, I have straightened quite a few coins with no visible "stretching". Coins that are bent more than a 45 degree angle will however be damaged beyond repair.

I do not use pliers or a vice, a single uniformed strike each time is better than slow pressure in my opinion.

My method is to put something like a cloth on something hard like a smooth concrete/Tiled floor, place the coin on top of the cloth, the same over the top of the coin, hold a piece of wood no thicker than 20-30cm (any thicker and the strike is absorbed) flat over the coin surface and then lightly strike the top of the wood with a rubber mallet or hammer, check after each strike, the coin will always revert to a flat state with no visible stretching on the surface.

Using this method makes contact with the entire surface of the coin with a single hit, this makes sure it is uniformed and does not warp while attempting to straighten it.

This is a tried and tested method with 100% success rate.
Restoration addict : Verdigris Removal : Zinc White spot removal : Iron Rust Removal : Silver brooch/necklace mount Removal
"This is a tried and tested method with 100% success rate." Thanks, Fluke. I'll give a try and let you know how it turns out.
Also if it won't become completely flat again after a few strikes, then turn the coin over and repeat, this will straighten it out completely.

It will work with no damage or visible stress marks, I can assure you of that.
Restoration addict : Verdigris Removal : Zinc White spot removal : Iron Rust Removal : Silver brooch/necklace mount Removal
Any coin purist (AKA coin nazi) reading this will be fainting in horror.

I've often wondered about this subject but haven't tried a remedy as I'd assumed, like others, that the metal would always be deformed even if the surface could be restored to a flat state. I have some nice high value silver coins which are in my junk silver box because of this problem. It would be nice to think they could be restored and rescued from an eventual trip to the smelting pot.
Non illegitimis carborundum est.  Excellent advice for all coins.
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well, I tried Fluke's method and it worked. Thanks. I have the coin soaking in mineral oil now to finish conditioning the coin.
Good thought I work on a 2700t will that be enough to straighten one ?
Quote: "pnightingale"​Any coin purist (AKA coin nazi) reading this will be fainting in horror.

​I've often wondered about this subject but haven't tried a remedy as I'd assumed, like others, that the metal would always be deformed even if the surface could be restored to a flat state. I have some nice high value silver coins which are in my junk silver box because of this problem. It would be nice to think they could be restored and rescued from an eventual trip to the smelting pot.
I thought I might get some backlash from deep rooted collectors who would be horrified as well Phil :O, getting away with it so far!

Some things I do with coins are not exactly normal for a collector, I roast coins to an almost glowing point to clean them, that's two horrific things at once, cleaning and heating. Then I give this method to straighten a coin with blunt force trauma, even though it is the best way as no direct pinpoint pressure is made on the coin itself as the wood cushions the blow and distributes the energy evenly across the coin surface at once.

A bent coin shouldn't be confused with a dented coin, that is a different story and cannot be flattened without warping the coin surface detail.
Quote: "Mark240590"​Good thought I work on a 2700t will that be enough to straighten one ?
I very much doubt it, you will need at least double that.
Restoration addict : Verdigris Removal : Zinc White spot removal : Iron Rust Removal : Silver brooch/necklace mount Removal
You could stick them on a train track and let the train do all the work. They get straightened out perfectly....but may look a bit strange afterwards ;)

:O

Its illegal to do that here. Our trains stop if there is a pile of leaves on the track, the law acts like a copper coin can derail the train. :.
Restoration addict : Verdigris Removal : Zinc White spot removal : Iron Rust Removal : Silver brooch/necklace mount Removal
My dad used to do it when he was a kid with the big style pennies, he reckoned that he got one that he did numerous times out to 20cm in diameter.
Quote: "Fluke":O

​Its illegal to do that here. Our trains stop if there is a pile of leaves on the track, the law acts like a copper coin can derail the train. :.
​I used to write IT systems for the railways and although the "leaves on the line" or "wrong type of snow" stories are always quite funny, there is some logic behind it.

(here comes the science bit)
On sections of the track, there are things called Train Describers (http://nrodwiki.rockshore.net/index.php/TD), which flag the position of the train. These train describers can be hundreds of metres apart, and only one train can be in each segment at a time. So if you have a length of track with TDs in sections A, B and C, a train comes along and triggers TD A, so the signalman knows the train has passed position A, and is en route to B . If the leaves are covering the TD at position B, it won't trigger. So the signalman still thinks the train is in section A and hasn't reached B yet, so won't let any other train into that section, which means the following trains have to stop and are delayed.
Only when the train passes TD C, does the signalman know that sections A and B are empty with no train is stopped there. And he's safe to allow a train into section A.

Hopefully I've explained that OK.

I was writing these systems about 25 years ago, I have no idea if any of the track hardware has been updated any, unlikely, but we were doing GPS trials about 20 years ago, but the technology at that time was too expensive and crude to roll out to the entire railway infrastructure.

The actual hardware for the train describers is quite archaic, it basically works like a switch, which is "made" when the wheels go over a specific part of the track and the wheel/axle completes the circuit and sends a signal to the signalbox. If that part is covered in leaves, the circuit won't be complete and no signal is sent, even though the train has passed.

Apologies for the treadjack, but I always got ribbed about working for the railway, especially when trains were delayed during the autumn for this reason, so I feel the need to explain. :D
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I'm not an expert in any kind of coins, but I reckon I'm good at research and will do my best to help. Feel free to tell me my identifications/valuations/gradings are wrong. It's the only way I'll learn.
Quote: "BizzoDoes"
Quote: "Fluke":O
​​
​​Its illegal to do that here. Our trains stop if there is a pile of leaves on the track, the law acts like a copper coin can derail the train. :.
​​I used to write IT systems for the railways and although the "leaves on the line" or "wrong type of snow" stories are always quite funny, there is some logic behind it.

​(here comes the science bit)
​On sections of the track, there are things called Train Describers (http://nrodwiki.rockshore.net/index.php/TD), which flag the position of the train. These train describers can be hundreds of metres apart, and only one train can be in each segment at a time. So if you have a length of track with TDs in sections A, B and C, a train comes along and triggers TD A, so the signalman knows the train has passed position A, and is en route to B . If the leaves are covering the TD at position B, it won't trigger. So the signalman still thinks the train is in section A and hasn't reached B yet, so won't let any other train into that section, which means the following trains have to stop and are delayed.
​Only when the train passes TD C, does the signalman know that sections A and B are empty with no train is stopped there. And he's safe to allow a train into section A.

​Hopefully I've explained that OK.

​I was writing these systems about 25 years ago, I have no idea if any of the track hardware has been updated any, unlikely, but we were doing GPS trials about 20 years ago, but the technology at that time was too expensive and crude to roll out to the entire railway infrastructure.

​The actual hardware for the train describers is quite archaic, it basically works like a switch, which is "made" when the wheels go over a specific part of the track and the wheel/axle completes the circuit and sends a signal to the signalbox. If that part is covered in leaves, the circuit won't be complete and no signal is sent, even though the train has passed.

​Apologies for the treadjack, but I always got ribbed about working for the railway, especially when trains were delayed during the autumn for this reason, so I feel the need to explain. :D
​I've just got in from walking the dogs and when I come in ITV had something on about it saying the leaves bake onto the track effectively shorting the electric link making the trains disappear from the control boards.
Thought this was fascinating. You explained that excellently.
Irony, I also saw a story on BBC news about trains have ceased on one line because of leaves. Aside from the reasons listed above, the reason they are worried is also down to damage from the brakes, If the wheels slide it can erode away one part to make it a little flat.

The reasons are highly valid, but still.......trains stopped because of leaves is funny. Especially as you can see videos like this ....

https://www.youtube.com/watch?v=uvbgq2Ni2uE :O
Restoration addict : Verdigris Removal : Zinc White spot removal : Iron Rust Removal : Silver brooch/necklace mount Removal
Quote: "Fluke"
Quote: "pnightingale"​Any coin purist (AKA coin nazi) reading this will be fainting in horror.
​​
​​I've often wondered about this subject but haven't tried a remedy as I'd assumed, like others, that the metal would always be deformed even if the surface could be restored to a flat state. I have some nice high value silver coins which are in my junk silver box because of this problem. It would be nice to think they could be restored and rescued from an eventual trip to the smelting pot.
​I thought I might get some backlash from deep rooted collectors who would be horrified as well Phil :O, getting away with it so far!

​Some things I do with coins are not exactly normal for a collector, I roast coins to an almost glowing point to clean them, that's two horrific things at once, cleaning and heating. Then I give this method to straighten a coin with blunt force trauma, even though it is the best way as no direct pinpoint pressure is made on the coin itself as the wood cushions the blow and distributes the energy evenly across the coin surface at once.

​A bent coin shouldn't be confused with a dented coin, that is a different story and cannot be flattened without warping the coin surface detail.

Quote: "Mark240590"​Good thought I work on a 2700t will that be enough to straighten one ?

​I very much doubt it, you will need at least double that.
​:(
the biggest one we currently have is 5000t I'll have to wait a couple of years for the new one before I can straighten some ;)
Not quite the West Coast Main Line is it? :D
http://www.facebook.com/NumismaticsUK
I'm not an expert in any kind of coins, but I reckon I'm good at research and will do my best to help. Feel free to tell me my identifications/valuations/gradings are wrong. It's the only way I'll learn.
Do you have any before and after pictures?
http://www.facebook.com/NumismaticsUK
I'm not an expert in any kind of coins, but I reckon I'm good at research and will do my best to help. Feel free to tell me my identifications/valuations/gradings are wrong. It's the only way I'll learn.

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