Sonic Sealing Slabs.

Oldtrader3 · June 25, 2008 9:57AM

I bought and received a 1964, PCGS, PR68CAM cent today in a slab that pulled apart when I tried to remove the dealers sale sticker. Does PCGS, Quality Assurance at least vacuum cup test the seal integrity before they package a slab and ship it? This particular slab had never been sealed. The slightly hermetic vacuum by closing the slab half, interlocking seal ribs was all that held this slab together. The sealing ribs on this slab had not been sonically melted. They were entirely intact.

I was an Automation Engineer on both toys and medical devices for many years and later a Plant Manager and a V.P. of Manufacturing before retiring. We used a great many Branson sealers on many of the plastic products which I was involved with over many years. Whoever is running a sealer needs to be certified to verify not only the air pressure on the horn, but also listen for the sub-harmonic squeal of the sealer while sealing and watch the seal intensity gauge on the front of the sealer or there is no seal. We either vacuum cup, pull-tested or vacuum tested all of our sealed products by in-process, Quality Assurance before they went to packaging. Apparently, this product was maybe visually inspected (85% accurate) or passed by another form of inspection.

In any event this was an unwelcome surprise which was returned to the dealer at my expense to be corrected. Your processes should be CpK tested, validated, certified and have controls in place to assure seal integrity. Apparently this sealing process is not under very strict, statistical control.

IGWT · June 25, 2008 10:02AM

Quality assurance is not as necessary for slabs as for medical devices or toys.

IGWT · June 25, 2008 10:12AM

Oldtrader3 · June 25, 2008 10:16AM

It should be. What if this was a $50,000. gold coin and it feel on a concrete floor at a show because it was not sealed?

Cameonut · June 25, 2008 10:17AM

I can see where it would be very possible for the sonic sealer operator to turn down the power to eliminate the irritating screech they give off when sealing.

But there should be some type of control in place otherwise PCGS is at risk of some hanky panky with the open holders.

adamlaneus · June 25, 2008 10:18AM

First, i'd have to say that for medical applications, toys, avionics and the like...you have some real product liability issues.

Slabs don't get off the quality hook because they are not life-saving devices.

One thing I wonder about is whether or not this slab had been cracked open by a coin doctor. That might explain a 'bad seal'.

I would assume that PCGS would fix this for free, as it would represent a defect in workmanship; that is something that should be covered under a basic warranty. Or something that might be corrected after a polite call?

turtal · June 25, 2008 10:26AM

With the way PCGS has influenced the coin market (particully in Bust Halves), i would think Quality Control would be their number one priority. God, they cant even put the coin in the holder straight half the time. The last time i got some halves slabbed 4 out of 10 were put in sideways. No quality control at ANACS either. Sent them some halves last year just when they switched to their new stle holders, got them back with some kind of glue residue on the sides.......

Oldtrader3 · June 25, 2008 11:05AM

The sealing ribs on both sides of the slab were intact, indicating that little or no sonic energy was directed through the slab. The ribs melt quite easily, even partially and these weren't touched. You can even put a small fluorescent bulb on the machine and hook it up or it will sometimes it will light all by itself if the 56KHz or whatever of frequency is there.

morgansforever · June 25, 2008 11:31AM

Speaking of sealing, I wonder if it's possible to de-seal a slab?

If it can be sealed sonically, why couldn't it be unsealed?

I'm not talking a hammer or a band saw.

Any thoughts?

Cameonut · June 25, 2008 11:58AM

<< If it can be sealed sonically, why couldn't it be unsealed? >>

In sonic sealing the plastic is melted together much like metal welding. The sonic energy is channeled thru a tuned horn and into the plastic pieces to be joined. When done properly, the weld is stronger than the base material.

So could a slab be unsealed? I don't know if it is feasible. All I know is that the parts I used to work on would not come apart easily. If replaced in the fixture and re-welded, it would be tough to get them apart before the plastic cooled. In any event, it would not be a very clean separation.

BAJJERFAN · June 25, 2008 1:22PM

Out of an $18 fee to grade and slab an economy level coin just how much time and $$$ do you think they are gonna spend on post-sealing testing. I'll wager not much if any. You ever seen the grading video where they show the sealing process? They run em thru there very fast, bing bing bing. The sealed slabs/coins are probably handled 2 or 3 more different times by different folks after sealing so if they don't come apart in someone's hands they are probably assumed to be ok.

Broadstruck · June 25, 2008 1:39PM

<< I can see where it would be very possible for the sonic sealer operator to turn down the power to eliminate the irritating screech they give off when sealing. >>

Thanks... I always wondered if the raw coins had any last words while gasping for their last breath prior to entombment!

bsb · June 25, 2008 1:58PM

Oldtrader3 · June 25, 2008 3:13PM

Sonic molecular excitation welding is focused at a normally 56Khz sound frequency that will melt engineering or crystalline types of plastic but will not heat metal at the same time. Once the two raised, specially designed, sealing ridges on each of the four sides of the slab are excited and fuse, the process can not be reversed by re-excitation. The friction of the weld has fused the ribs together to the extent that they no longer exist as discrete features. In other words the metal does not heat inside the slab. The energy is focused by the sonic horn on a small area of the periphery of the plastic slab. The coin is not affected by his frequency level. It would take a higher frequency, up in the microwave frequency region to heat the coin. I would pay an extra buck to assure quality and weld integrity. The 56KHz sonic range is localized, is not high enough frequency to heat the coin and has nothing to do with color changes. Coin doctors cause coin color changes.

Actually, we were able to make medical devices that cost half as much and went from 30 failures/million parts to 1 failure/10 million parts+ with no human inspection, except final audit, through process control and selective automation. We had to in order to keep the Japanese out of our shorts. The Japanese never could match our quality levels. The coin slabbing industry is still in the engineering dark ages. They have the volume for these techniques but are too technically naive to know how to fix their problems. Plus they charge much more for their services than medical device firms ever will for low technology devices with Medicare DRG rulings. You may pay $30. for a catheter in the hospital, but the hospital pays less than $1.00 for it.

BECOKA · June 25, 2008 4:24PM

Quality control is not always at it's best.

I have had mis labeled slabs, slabs with plastic pieces floating around, hairs stuck inside etc...

PerryHall · June 25, 2008 6:09PM

Sounds like a serious security breach on the part of PCGS. Someone could use each shell half to create a mold to mass produce counterfeit slabs. I wonder what unsealed PCGS slab shells would bring on eBay?

halfhunter · June 25, 2008 8:23PM

listen for the sub-harmonic squeal of the sealer while sealing and watch the seal intensity gauge on the front of the sealer or there is no seal.

I well know what you mean by that squeal. One of our converting lines have 7 Hermann Ultrasonic Sealers, bonding various webs together. The converter has alot of the noise engineered out but couldn't get rid of the squeal, so we still have to wear hearing protection.

Sorry for the OT but just found it interesting that this is common to all Ultrasonic sealer/bonders.

Regards, John

BAJJERFAN · June 25, 2008 9:29PM

<< The coin slabbing industry is still in the engineering dark ages. They have the volume for these techniques but are too technically naive to know how to fix their problems. Plus they charge much more for their services than medical device firms ever will for low technology devices with Medicare DRG rulings. You may pay $30. for a catheter in the hospital, but the hospital pays less than $1.00 for it. >>

Unlike your volume which is likely all 100% identical pieces each being made exactly like the other, in the slabbing business a run might be one coin for a reholder, 6 coins for your order, 8 coins for my order etc. and so on and so forth. Its hard to effectively automate a process which has so many discontinuities and breaks in it. Afterall its important that each customer get THEIR coins back, a hospital probably doesn't care at which point in a production run their catheters were made. I do not think that I would pay an extra dollar to solve a problem that occurs 1 in a million times.

ricko · June 25, 2008 11:35PM

The basic premise of the OP is that any customer oriented business should have at least minimal Quality controls in place to assure the customer of a good product. That being said, this is the first instance I have heard of (after nine years on this board - well, one and a half on the old board to) here on this forum. If that is their failure rate, it is likely very good... However, I have certainly not read each and every thread posted, so there may have been others. Nonetheless, I would report this to customer service in a formal letter, giving all details. Cheers, RickO

Shamika · June 26, 2008 12:03AM

<< Sounds like a serious security breach on the part of PCGS. Someone could use each shell half to create a mold to mass produce counterfeit slabs. I wonder what unsealed PCGS slab shells would bring on eBay? >>

You could certainly mix and match coins and labels to your advantage. Imagine putting a coin that graded MS65 with a MS67 label. Since many collectors can't seem to tell the difference between these two grades, it would be an easy score for the perpetrator.

Bochiman · June 26, 2008 12:19AM

I'd wonder about the people who had the slab before you....if it came apart so easily once the sticker was removed, why didn't anyone notice/do anything before?
Hope the coin matched the grade on the slab

19Lyds · June 26, 2008 12:26AM

To me, this sounds like the slab never made it into the sonic sealer. Marty had one a month or so back and I'm sure this will occur again in the future.

In a business that deals with hundreds of thousands of coins a month, I'm actually surprised that this does not occur with more frequency.

Goof Ups happen.

seanq · June 26, 2008 12:35AM

<< 

<< The coin slabbing industry is still in the engineering dark ages. They have the volume for these techniques but are too technically naive to know how to fix their problems. Plus they charge much more for their services than medical device firms ever will for low technology devices with Medicare DRG rulings. You may pay $30. for a catheter in the hospital, but the hospital pays less than $1.00 for it. >>

Unlike your volume which is likely all 100% identical pieces each being made exactly like the other, in the slabbing business a run might be one coin for a reholder, 6 coins for your order, 8 coins for my order etc. and so on and so forth. Its hard to effectively automate a process which has so many discontinuities and breaks in it. Afterall its important that each customer get THEIR coins back, a hospital probably doesn't care at which point in a production run their catheters were made. I do not think that I would pay an extra dollar to solve a problem that occurs 1 in a million times. >>

Your point is something of a red herring. PCGS uses a single style of slab, which is sealed the same way regardless of what type of order it was or what kind of coin is inside. The kind of automated quality control the OP is talking about would be the very last step before verification and shipment back to the submitter and done right should add very little time or cost to the grading process.

Sean Reynolds

tahoe98 · June 26, 2008 12:45AM

<< It should be. What if this was a $50,000. gold coin and it feel on a concrete floor at a show because it was not sealed? >>

then you would need a prescription...........

BAJJERFAN · June 26, 2008 1:43AM

<< The basic premise of the OP is that any customer oriented business should have at least minimal Quality controls in place to assure the customer of a good product. That being said, this is the first instance I have heard of (after nine years on this board - well, one and a half on the old board to) here on this forum. If that is their failure rate, it is likely very good... However, I have certainly not read each and every thread posted, so there may have been others. Nonetheless, I would report this to customer service in a formal letter, giving all details. Cheers, RickO >>

If you go back and watch the promotional video about their grading process you will see that they do have QC, just that putting the sealed slab into a suction device to test the seal is not a part of it. I'd guess its a very rare problem and that expensive coins are somehow checked. If someone has an idea for a low cost easy to use device I'm sure they'd listen.

Shamika · June 26, 2008 1:59AM

<< To me, this sounds like the slab never made it into the sonic sealer. >>

Not necessarily. For ultrasonic sealing to work, there must be a special kind of rib molded along the seam of the slab which, consequently, will be the last part filled during the injection molding sequence when these shells are manufactured. And it's my guess that these shells are not molded by PCGS. Tasks such as this are often out-sourced to one of the many custom molders around the country at the direction of PCGS. Although PCGS may own the molds for these shells, they would not want to bother with the very large and maintenance intensive molding machines. Again, my guess is that PCGS orders a large number of shells from their custom molder on an as-needed basis and then all the sonic weilding is done in-house. If the mold cavity is not completely filled by the manufacturer i.e."packed out", you will have what is called a "short shot". And with the almost invisible rib missing, the shells will never seal correctly.

astrorat · June 26, 2008 2:03AM

<< With the way PCGS has influenced the coin market (particully in Bust Halves)... >>

Please explain how PCGS has particularly influenced the coin market in Bust halves...

Lane

Oldtrader3 · June 26, 2008 4:06AM

Actually medical devices companies are much like custom electronics companies who produce many SKU's that are discreet and not alike. As was mentioned, all PCGS slab halves are identical dimensionally as far as the sealing operation is concerned. There is only one product at PCGS sonic sealing stations. Where I worked we made over 1500 SKU's of product.

That is why you need a simple in line test, to find a short plastic molding shot or incomplete weld which can not be seen well and can not easily be checked by twisting the slab halves (unlike NGC slabs) because of the thinness of each half. Any person with basic technical skills could look at the process, devise and design a quick and cheap, non destructive test to eliminate no seals or relatively weak seals. This is not rocket science!

BTW the 1964, PR68CAM, cent in the slab was correctly graded IMHO. I believe that the dealer whom I bought it from probably submitted it to PCGS. It was held together fairly tightly by a natural vacuum and friction created by the seal bead fit interface.

astrorat · June 26, 2008 4:57AM

Charles-

The explanation is quite simple...PCGS made a mistake. The person did not seal the coin and it slipped past the final quality check. Mistakes happen.

A few years ago I received a coin from NGC that was not sealed. The irony was that it was a sample slab used to promote the quality of their holder. LOL! Mistakes happen.

Considering that PCGS has slabbed over 16 million coins and rarely have unsealed holders reached the market, one can only conclude that their quality control with respect to sealing coins is quite high.

What if it were a $1,000,000 Saint Gaudens that fell to the concrete floor that bounced along only to be stepped on by a 300-lb, cheeseburger-toting coin dealer, who fell to the floor breaking a hip cursing and causing the Buffalo nickel sorting Boy Scout next to him to cry and in his anguish he knocked over his cherry cola spilling onto a collector's gem fractional notes who became so enraged he brandished his mechanical pencil and attacked the poor show page who...etc, etc...

PCGS made a mistake with a coin...this ain't life and death.

Lane

Edited for spelling...

astrorat · June 26, 2008 5:01AM

<< There is only one product at PCGS sonic sealing stations. >>

Actually, there are at least two. PCGS also has (or at least recently had) a multi-coin holder that was used for State quarter sets and American Gold Eagle sets.

Lane

Oldtrader3 · June 26, 2008 2:19PM

No, Lane, it isn't life or death. You are a PhD in Pharmacy and know that Bayer can make 10 billion+ aspirin a year that wholesale for $1/100 without miscounting or misdosing even one of them, even when compounding them in Puerto Rico where the work force couldn't care less about quality. Simple engineering prevention measures would make this problem go away and probably save money in the process. That makes it a big deal when a service that people pay good money for, and wait longer than advertised periods for, fails the customer. It IS totally unnecessary! Have you ever worked in the pharmaceutical industry or as a Pharmacist? You should know that this can be statistically eliminated at minimal cost.

astrorat · June 26, 2008 11:28PM

<< No, Lane, it isn't life or death. You are a PhD in Pharmacy and know that Bayer can make 10 billion+ aspirin a year that wholesale for $1/100 without miscounting or misdosing even one of them, even when compounding them in Puerto Rico where the work force couldn't care less about quality. Simple engineering prevention measures would make this problem go away and probably save money in the process. That makes it a big deal when a service that people pay good money for, and wait longer than advertised periods for, fails the customer. It IS totally unnecessary! Have you ever worked in the pharmaceutical industry or as a Pharmacist? You should know that this can be statistically eliminated at minimal cost. >>

The pharmaceutical industry and coin slabbing are apples and oranges. The consequences of errors between the two are utterly different as are the precautions to prevent them. And just to set the record straight, the pharmaceutical industry spends billions of dollars to ensure the quality of their products and are required to follow strict federal and international standards, whether the products are manufactured in Puerto Rico or New Jersey. And please don't think that they are absolutely error free, as they are not. And by the way, it is wrong the think that pharmaceutical industry workers in Puerto Rico "couldn't care less about quality."

Of course, PCGS could remedy the "problem" if they chose to do so. But ask yourself a much more pragmatic question...why would they? They have a huge, satisfied customer base, they lead the industry, and have so much business that they are constantly "behind schedule" with little end in sight. If it really is an issue, then dissatisfied customers will go elsewhere and PCGS will fix the "problem." If one takes an overview of the industry there are far greater issues than the, perhaps one in a few million, slabs that get released but are not sealed.

And just because you asked...yes, I have worked as a pharmacist in the community and institutional settings in addition to being a consultant to the pharmaceutical industry in manufacturing, clinical trial design, data analysis, and patents for the past dozen years (even while I was at the ANA).

Lane

Edited for spelling...

BAJJERFAN · June 27, 2008 12:47AM

Its easy to sit here and say what PCGS should do. If it was YOUR decision would you spend $100K of the company's money on a problem that is extremely rare. I do not think I would. Since they don't warrant the slab to be air-tight even a mediocre seal is good enough.

Placid · June 27, 2008 1:11AM

Sorry couldnt resist

seanq · June 27, 2008 1:29AM

<< Its easy to sit here and say what PCGS should do. If it was YOUR decision would you spend $100K of the company's money on a problem that is extremely rare. I do not think I would. Since they don't warrant the slab to be air-tight even a mediocre seal is good enough. >>

I'm not sure where you got that dollar figure, but this problem could be eliminated for a small fraction of that, and with a minimal impact on the flow of product out the door.

I do agree that you could question why PCGS would spend any money at all on it given the rarity of this production defect. I would counter that with the point that without a fail-safe inspection program, what is currently a very small problem could easily become a large problem and PCGS would never know until the unsealed holders hit the streets.

If it were my company, I'd consider it small investment in ensuring the intergity of my product (and thus my reputation).

Sean Reynolds

BAJJERFAN · June 27, 2008 1:55AM

<< Actually medical devices companies are much like custom electronics companies who produce many SKU's that are discreet and not alike. As was mentioned, all PCGS slab halves are identical dimensionally as far as the sealing operation is concerned. There is only one product at PCGS sonic sealing stations. Where I worked we made over 1500 SKU's of product. >>

Not really relevant since I assume that each of those 1500 SKU's are produced one SKU to a run and there might be more than one production line going. I doubt that Chevy produces Corvettes and Suburbans randomly on the same production line at the same time.

BAJJERFAN · June 27, 2008 1:58AM

<< 

<< Its easy to sit here and say what PCGS should do. If it was YOUR decision would you spend $100K of the company's money on a problem that is extremely rare. I do not think I would. Since they don't warrant the slab to be air-tight even a mediocre seal is good enough. >>

I'm not sure where you got that dollar figure, but this problem could be eliminated for a small fraction of that, and with a minimal impact on the flow of product out the door.

I do agree that you could question why PCGS would spend any money at all on it given the rarity of this production defect. I would counter that with the point that without a fail-safe inspection program, what is currently a very small problem could easily become a large problem and PCGS would never know until the unsealed holders hit the streets.

If it were my company, I'd consider it small investment in ensuring the intergity of my product (and thus my reputation).

Sean Reynolds >>

My assumption is based on the probability they would need to hire a full time person at liveable California wages plus benefits and some outside engineering work. I'd say most of the obvious ones are caught before they leave PCGS. Then again we don't know what they do in the way of QC; the fact that they may not do anything is pure speculation.

Oldtrader3 · June 27, 2008 5:02AM

Come on, guys, does PCGS want product integrity or not! In fact I believe that this could be done on a fixture that costs $10-$15,000, by a QA inspector that they probably have already visually inspecting ineffectively, at maybe 85% efficiency and accuracy on a good day. This would assure better quality control than any human inspection. Plus, for a few bucks they could validate the sealing parameters, establish process capability within +/- 3 sigma and qualify the sealer operator. Maybe they could even have the sealer operator load another station simultaneously to loading slabs for welding and test a welded slab while she is waiting for the slow sonic welder (with probably a 2+ second cycle) to finish it's cycle. A small, slow turntable with small Bodine motor (under $150.00) and a foot pedal and with shallow pockets next to the sealer operator could be curing welded welded slabs for her to test. The turntable could be painted plywood with wood molding nests. Then put finished slabs back in their in their tote, on a small conveyor to packaging. With certification and qualification they could most likely drop visual inspection down to (30) welded units per hour. I would bet that this can be done for less money than they currently spend, despite California wages and benefits costs. The fixture expense amortization would probably be paid for a few months. This is like shooting ducks in a barrel!

We did this same validated process, simple fixturing exercise in rural China and Nogales, Mexico with extremely high reliability. The fixtures were even designed and built in the USA. These methods were used were for very inexpensive kits with hourly, or less SKU changes.

If they added a second welder mounted on the same table and a double fixture, the operator could load from both sides and inspect two sealing stations at once, if this process was validated. That would double the sealing output for the same cost and free up expense monies to build a fixture with a small conveyor, to test welded slabs. I bet there are (10) permutations of line arrangement and fixturing that could produce 2X+ as many sealed slabs, with the same number of people and 10X better quality control numbers than they have now. I did this for a living for nearly (40) years and this is not smoke and mirrors.

BAJJERFAN · June 27, 2008 6:09AM

You shud scare up the grading video first, I'm sure someone here can linky it for you. IIRC they seal the slabs pretty quickly. Also you might try posting your concerns on the Q & A forum.

Oldtrader3 · June 28, 2008 3:23AM

Good idea. If I wasn't ill now with DVT and Bronchitis, I would drive down to Newport Beach and spend a day or two with them for free, if they would show me their process. Since I am retired and disabled, I don't care much about making money now. I know that this could be fixed for not much money. Robust processes are a culture as much as science.

BAJJERFAN · June 28, 2008 3:56AM

<< Good idea. If I wasn't ill now with DVT and Bronchitis, I would drive down to Newport Beach and spend a day or two with them for free, if they would show me their process. Since I am retired and disabled, I don't care much about making money now. I know that this could be fixed for not much money. Robust processes are a culture as much as science. >>

Well I'm not so sure I believe that because someone got one bad slab, that their system is necessarily broken.

drwstr123 · June 28, 2008 4:40AM

<< 

<< Good idea. If I wasn't ill now with DVT and Bronchitis, I would drive down to Newport Beach and spend a day or two with them for free, if they would show me their process. Since I am retired and disabled, I don't care much about making money now. I know that this could be fixed for not much money. Robust processes are a culture as much as science. >>

Well I'm not so sure I believe that because someone got one bad slab, that their system is necessarily broken. >>

I've been around long enough to know it ain't perfect.

PerryHall · June 28, 2008 4:48AM

<< 

<< Good idea. If I wasn't ill now with DVT and Bronchitis, I would drive down to Newport Beach and spend a day or two with them for free, if they would show me their process. Since I am retired and disabled, I don't care much about making money now. I know that this could be fixed for not much money. Robust processes are a culture as much as science. >>

Well I'm not so sure I believe that because someone got one bad slab, that their system is necessarily broken. >>

This is not an isolated instance. Madmarty got one and I'm sure others have too.

BAJJERFAN · June 28, 2008 5:33AM

<< 

<< 

<< Good idea. If I wasn't ill now with DVT and Bronchitis, I would drive down to Newport Beach and spend a day or two with them for free, if they would show me their process. Since I am retired and disabled, I don't care much about making money now. I know that this could be fixed for not much money. Robust processes are a culture as much as science. >>

Well I'm not so sure I believe that because someone got one bad slab, that their system is necessarily broken. >>

This is not an isolated instance. Madmarty got one and I'm sure others have too. >>

I know that , but how many does it take to say its broken? There is an opportunity to address it on the Q & A board as it looks like they still field questions there.

Oldtrader3 · June 28, 2008 5:51AM

The process could probably be made robust to the level of one failure per 10 million (theoretical) units, or almost never.

drkilmer · June 29, 2008 12:49AM

The very first time I sent something in for grading, it came back with an unsealed slab. Disappointed? Yeh! Of course I sent it back and they fixed it ... but come on! That should not happen. I'd settle for longer turn around times if need be.

I think if I purchased something from a dealer that turned out to be in an unsealed slab I would return it and ask for a refund. Perhaps the dealer was the original recipient and could return it to be resealed.

Whish brings up an important point ... I do think it is incumbent on the person receiving the slab from the grading service to inspect it upon receipt and return it if it is unsatisfactory.

PerryHall · June 29, 2008 12:57AM

I wonder what an unsealed top tier slab would bring on eBay?

lathmach · June 29, 2008 6:46AM

I don't do the slab thing but here's my take.
If you had an expensive coin come back in an unsealed slab, couldn't you replace that coin with an inferior coin and super glue the case together and peddle it?
Seems like the thief in a guy would want the better stuff to come back unsealed.

Ray

Doogy · July 5, 2008 1:34PM

good thread, lots of scientific approaches presented here.

foodude · July 5, 2008 2:15PM

If you contact customer service on Monday, they should be very interested in getting the unsealed slab back, and getting your coin in a sealed holder.

Sonic Sealing Slabs.

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