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 Replies: 20 / Views: 28,255 |
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New Member
United States
1 Posts |
I just acquired a lovely (if real) 1803 Draped Bust dollar (large letter), however, it is encapsulated in a 3x2x1 inch acrylic rectangle. Can anyone recommend how I might free the coin from the block of acrylic - without damaging the coin? JWalker Image:  1803Obversedollar.jpg87.86 KB Image: 1803Reverse.jpg73.12 KB Edited by JWalker
06/16/2008 10:06 am
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Moderator
 United States
6563 Posts |
 Dremel tool...if you can saw a big enough gap you might be able to pry it out. I can't think of any way to do it without damaging the coin. Got Pics? |
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Forum Dad
 United States
24149 Posts |
It's very difficult. We sold these in 2005 for $26.30...  The description was as follows... Quote:This is a pair of Morgan silver dollars that have been encased in acrylic with timers. Someone apparently tried to remove both of these from the acrylic as the casing is cracked from obvious hammer blows or something along those lines. Both of these coins appear to be polished within the acrylic. The dates are 1890-O and 1921-S. Both have beautiful detail with wear evident on the breast feathers. Neither coin appears to have been damaged in the attempt to "free" them. The 1890-O measures 3-3/8" square by 1" thick and the 1921-S measures 3-3/8" square by 15/16" thick. The 1921 has a clear insert that says "The City National Bank of Austin". Please look at the picture below and read our payment and shipping terms prior to bidding. |
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Valued Member
United States
381 Posts |
I would use a dato blade smaler then the width (the smallest edge). Cut close but not to close to the coin. Then pry the hole you created with needle nose or those flat head vice grips. IF it give you problems then continue around all four sides.
Edited by jeffreyice1
06/15/2008 03:25 am
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Pillar of the Community
United States
1231 Posts |
You could try acetone or denatured alcohol to see if it will dissolve or soften the acrylic.
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Pillar of the Community
United States
954 Posts |
I know one method I have heard discussed was liquid nitrogen to super freeze it before hitting it with a hammer. I have never heard of anyone having any luck getting anything out.  |
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Pillar of the Community
United States
954 Posts |
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Valued Member
United States
311 Posts |
The problem is that the acrylic has likely bonded to the coin.
I've managed to bend thin sheets of acrylic with a heat gun... Based on that, i'd get a spare toaster oven from the Salvation Army, plug it in outside, crank it up to 450, and leave the coin in it for an hour or so... Of course, i'd probably also get a less desireable coin, similarly encased, to try this on first...
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Forum Dad
United States
24149 Posts |
Quote:
I would use a dato blade smaler then the width (the smallest edge). If it's anything like the ones pictured above..... nope. That stuff is hard, you're not going to cut it by hand with any knife. |
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Member
United States
3242 Posts |
I would try to trim it down to about 1/4 above coin on each side if I could find away to cut it. then set in some acetone and remove liquid daily until it was all gone and coin was all that was there. But that may take weeks or longer it a good thing acetone is cheap compared to gas that may also free coin but acetone is better plus it may not blow up as fast as gas  |
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Bedrock of the Community
United States
12437 Posts |
Acetone, rubbing alcohol, or anything else of the sort will not touch acrylic, aka Lucite. This is the same stuff that modern non glass bullet proof windows are constructed of. Bobby was correct in saying that this stuff would be next to impossible to cut through. Other than fire, which would irreparably damage the coin, the best bet would be extreme cold. Becky had the right idea with liquid nitrogen(-197.3C, -323F)- that should be cold enough to make the acrylic brittle but it will not damage the coin(as long as you don't hit the coin with the hammer  ). Liquid nitrogen is not exactly an easy item for most people to obtain though. It is possible that dry ice(-79C, -110F) might be cold enough but I am not sure. Dry ice can be obtained from most ice companies and butcher shops. I have access to both of these items so I might have to try it out sometime  |
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Pillar of the Community
United States
2443 Posts |
I know NCS is able to remove it. I've also heard that acetone works(I I think that's mainly used to just get a layer that's attached itself to the coin and not for the whole cube).
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Bedrock of the Community
United States
17884 Posts |
Trim it down with a bandsaw and the liquid nitrogen method will work. Dry ice might work. The key is the extreme cold makes the plastic brittle (soo the colder the better), and the big difference in expansion rates between the plastic and the metal of the coin works to pop the plastic loose from the surface of the coin.
And yes people have had success removing coins from lucite.
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Valued Member
United States
381 Posts |
Bobby131313. My fault for the miss spelling, I ment Dado not Dato. Its not by hand its usally on a table saw. http://en.wikipedia.org/wiki/Dado_bladeOr should say wobble blade, Available at home depot. It Gives you a cut to a set width which you can control. If you do this all the way around the coin, it should give you the cabablity of seperation. If you have a mic I would set the dado to the width of the coin. And you can adjust the height on the table saw by site. Edited by jeffreyice1
06/16/2008 02:29 am
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Valued Member
United States
377 Posts |
Heat it up with a blow torch, not enought to hurt the coin though, and drop it in some really cold ice water.. tht should crack it.
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Forum Dad
United States
24149 Posts |
I see a problem with cutting this with any type of mechanical saw. Although this stuff is almost as hard as metal, it's still a type of plastic and will melt. I think and sort of powered saw blade will gum up very quickly with melted acrylic and need to be cleaned every fews seconds of cutting. This is just an assumption though, I've never actually tried it.
Try taking it to your local high school and see if the chemistry teacher will dunk it in the liquid nitrogen tank and smash it for you. Heck, maybe you can do it in front of a class... Coin Collecting Chemistry 101.
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Replies: 20 / Views: 28,255 |
1803Obversedollar.jpg
1803Reverse.jpg
Posted 06/14/2008 11:36 pm
