Why can't a slab be 100% airtight and watertight ?

I didn't see anything that said the slabs were waterproof. Also, I think people are more concerned about airtight than waterproof. Osmosis is less likely than molecular penetration of smaller elements, FWIW.

 

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Not my claims - but I know the owner of CCCS, during the 2007 RCNA convention in Ottawa, when he introduced those slabs, took one of his slabbed coins and threw it in hotel's water fountain for a full day and night - then pulled the coin out the next day to display for everyone to inspect. Water proof in the strictest sense of the word?? Probably not, especially with any decent water pressure - but certainly enough to protect your coins from flooding (which was the example given earlier in this thread).

I would like to prove it you - but I like to play the registry set game, so I don't have any of my coins in CCCS hard slabs. Plus, their grading is not as consistent as PCGS (I am a PCGS fan for grading of Canadian coins). Most collectors I know use CCCS to slab error coins or one of the oddball Canadian varieties - because simply it is cheaper than sending error coins south of the border to NGC or PCGS - we have no other alternatives for hard slabs up here.

I agree with you 100% about the lack of advertisement with this company and their website. They are shooting themselves in the foot with such a poor marketing strategy - a fact well known in the Canadian collecting community. Also, the owner of CCCS (Louis Chevrier) owns Lower Canada Auctions: http://www.lowercanadaauction.com/ (a potential conflict of interest, in my opinion, especially when auctioning off CCCS certified coins) - so they dropped the ball with advertising completely - that poor website has not been updated since like 2004... In my opinion, if they really wanted to market their stuff, they should have a slabbed coin sitting inside a fish tank, right on a table at a coin show...

 

I think we will see it in the near further the teck is in place to do it with monster glass. Will probably be a upper end type of grading and preservation service that might cost at least $100.00 or so per coin. Not for the common stuff but see a market for the high end items.
Would see items like the 1943 copper cents in something like this to insure they stay stable.

 

To answer your question, yes, current existing technology can be adapted to overcome the problems of "slab outgassing", moisture/gas entrapment/migration, differential pressure destruction, mechanical bond destruction, integrity of bond, etc.. Now, longevity of seal integrity is another subject.

I've designed/applied appropriate technology in the past to rapidly sterilize/stabilize the atmosphere inside of medical products wrappings, implementing a hermetic seal for shipping/storage without contamination.

It would require "thinking outside the box" of current slab design. If I thought that economics/demand would justify same, I'd apply for a patent on the slab design. I believe the immediate facilities/equipment for environmental alteration/isolation, encapsulation, housing redesign aren't justified by the gains realized, potential interest, nor economics/liabilities.

Unlike food products which have a relatively short "use life" (i.e. "use by date"), the slab would need a design to resist degradation for probably minimally a century, or the degradation life of the housing material. Current housings (i.e. "slabs") have hardly existed for a quarter century, and I wouldn't expect a "seal" applied to current design to last even a couple decades.

JMHO :thumb:

 

Maybe I should purchase a cheaper example in one of those slabs and do an experiment with immersion and timed photography. Or send in a brown large cent, and then immerse the slab in vinegar - that should photograph well!

In the meantime, I have sent an email to the owner of CCCS, asking him for further details. I'll share the reply.

 

You know, we do have the technology to do a truly airtight display holder -- every LCD display and every plasma display is "truly airtight". They're cheap to manufacture in bulk, and they tolerate the pressure changes associated with air shipping.

On the other hand, I don't know how well you could adapt those processes to accept individual coins, rather than mass-produced identical display circuitry.

 

Simple Modifications/Procedures Would Allow Sealed Holder!!

When I designed a production facility for sealed Fresnel lenses 40+ years ago, I used a robotic X-Y-Z servo driven table to apply a continuous bead of Silicone adhesive (in a controlled atmosphere) between the outer layers and the inner lens. This design allowed a hermetically sealed plastic lens relatively impervious to adverse outside conditions. I believe this technology is currently used with Ultra-Violet cured adhesives to produce the products to which you refer.

The afore-mentioned process is acceptable for relatively "short-lived" commercial products. The mitigating application of adhesive is acceptable for products of the nature discussed, but probably isn't conducive for an acceptable precious coin seal, because of potential "out-gassing", and longevity of adhesives. A labyrinth would need to be installed between the inside and outside surfaces to eliminate "gas" migration.

There is a commercial product currently on the market, which I believe when minutely modified, applied in a controlled environment, and properly sealed would effect the desired seal. The seal could be generated through Ultra-Sonic bonding, and UV adhesive exterior application.

I suspect that with proper procedures and a desiccant environment, a novice could also relatively inexpensively protect their coins at home with minimal effort.

JMHO :thumb:

 

Good idea!

In the mean time, here are some photos of an Everslab made by Leuchtturm, 5 min. under water...

http://monety.pl/viewtopic.php?p=176253&highlight=#176253

 

Why would I want to read it again?

 

Ok, I just want to point out that there was a thread in one of the other forums in which I discussed topics such as airtight, vacuum sealed, etc. It sounds like the original poster was asking if slabs are currently airtight or vac sealed, and if they aren't sealed properly could they be at a price which would not be cost prohibitive. Answers are current slabs are advertised as being "airtight" (no vac seal), and with regards to the second question the cost of properly storing coins for the LONG HAUL can be done fairly inexpensively though it would require someone with both the know how and the proper tools to maintain coins in a state of preservation. Steamfitters, Refer Techs, Maint. Tradesman, these would be people who would most likely be able to design a means of storage. The main problem todays TPG slabs have is that they are unfortunately made of a plastic. Plastic, by its its very nature, IS NOT USED IN THE CONSTRUCTION OF A PRESSURE VESSEL. Plastic is porous and simply can not be sealed. Metal (copper, brass, stainless) and Glass can be fashioned into pressure vessels. I would be happy to post a more thorough and clear description of the various terminology being used, and how to understand what is what.

 

I am not sure. Is an ultrasonic weld capable of holding or maintaining pressure or a vacuum?

 

I believe you'll find I stated an optimum process would be conjunctive "The seal could be generated through Ultra-Sonic bonding, and UV adhesive exterior application".

A direct answer to your question is YES, when a properly designed labyrinthical (versus flat surface bonding) round seal is produced. A round ultrasonic horn of the correct mass, applied at a proper frequency, could easily effect same. I could easily enjoin with a manufacturer of an existing product to produce an economical effective enclosure.

In my opinion, the companies charging Megabucks for their services appear to be limited in their "outside the box" thought processes when redesigning their products. I'm certain that I could enjoin with any of them to produce a premier effective product. I believe the problem is merely the NIH manufacturing syndrome, and political management with limited technical skills.

JMHO

 

Thank you all for the information, this is quite informative. 'imrich', your knowledge of sealing processes brings a lot of interesting data to the table.

 

Tell that to any bottle of pop. I believe if it keeps the pop and bubbles in, it would suffice for coin purposes, no?