Welcome to my blog. I use data to help collectors make informed decisions about buying and selling sports cards. I hope you find the analysis presented on this blog entertaining and useful!

Cuts Like a Knife - Part 1

Cuts Like a Knife - Part 1

Lately, there have been a lot of conversations about sports card scams.  Some scams involve counterfeits.  Others involve shill bidding.  Then there is pack searching and resealing.  No doubt, all of these things happen.  By association, it can give many the impression that all collectors are dirtbags.  I know that not to be true.  Hang in there good guys.  But, there is another scammer activity that has me interested, card trimming.  In my opinion, it could be the single hardest scam to detect.  To compound matters, it arguably presents the largest potential financial gain to the scammer as well.  Just look at the most valuable and famous sports card of all time, the ‘Gretzky’ T206 Honus Wagner baseball card.  Under oath in a Federal plea agreement, Bill Mastro confessed to trimming the card.  So, if you believe the testimony, the most valuable sports card of all time is altered.  It’s also residing in a PSA 8 holder.

This got me thinking about modern sports cards.  How could a collector reasonably judge if a card has been trimmed?  There is definitely some good information to be found on the internet.  But, I wanted to take a bit of a different approach.  I would like to first have some understanding of the manufacturing methods use for creating sports cards.  There are several videos available on YouTube showing cards being cut and packed.  First, let’s look at a video posted by Panini.  It shows 2010 Panini Gridiron Gear Football being packed out.

At around the 0:16 mark, you can see the cards as they have been cut into strips from a card sheet.  The cuts made in this step set the height of the card, which is the dimension that is approximately 3.5 inches.  Then at the 0:39 mark you can see how the cards are cut across the width dimension. 

I also find it interesting the rate at which the sheets of cards are cut.  At the 1:14 mark the video shows a counter.  The counter increases by 2 over the course of 6 seconds.  I assume the counter increments by one each time a sheet of cards is loaded to be cut.  That feed rate would equate to around 20 sheets of cards every minute, 1200 sheets every hour, or 9600 sheets in an 8 hour shift.  Each sheet appears to have cards in 10 rows and 10 columns, resulting in 100 total cards per sheet.  That means in a single shift, Panini could produce 960,000 cards.  I went back and found a post on Blowout Forums detailing the product launch for 2010 Gridiron Gear Football.  Here’s the case configuration.

16 boxes per case, 18 packs per box, 5 cards per pack

That’s about 1440 cards per case.  So, in an 8 hour shift, Panini would have roughly produced just over 650 cases of this particular product.  I know that calculation wasn’t terribly relevant to the topic of this post, but it was fun to figure out anyway.

Let’s go back to the cutting process in the Panini video.  The cuts appear to happen as a result of a set of wheels that rotate.  I am familiar with many manufacturing processes, but not the specifics of manufacturing processes used for cutting paper or card stock.  From what I can find online, I suspect the equipment is called a cardboard slitting machine. 

One company that manufactures this type of equipment specifically for the purposes of producing trading cards and playing cards is Rollem International.  Here is a link to a sales sheet for one of their pieces of equipment.  The Rollem Slipstream looks really similar to what is shown in the Panini video.  There appear to be slitter blades that slice through the cardboard like a pizza cutter slices through pizza.  Rollem claims the tolerance on the cuts is within 1/1000th of an inch (0.0001”).  As someone that has done their share of mechanical engineering work, that seems like an incredibly small amount of variation, so I’m skeptical.  Here is a Rollem machine in action making a card deck of some kind for Vulcan Information Packaging.

Finally, if you’re into this kind of thing and you’re a fan of How It’s Made, here is a video showing how playing cards are made using this process.

As a side note, How It’s Made makes manufacturing facilities seem like a pleasant environment.  What’s better than cool machines, a soothing voice, and some soft music playing the background?  If you’ve ever worked in a manufacturing plant though, you know that this couldn’t be further from the truth.  The reality is there are continuous ear-splitting sounds of machines slamming, clanking, and humming, the burn your nose smell of various materials and chemicals, and long, hard days doing repetitive work.  Don’t let TV make it more glamorous or hospitable than it really is.  I have huge respect for people that endure this work and environment on a daily basis.

Back to sports cards again.  Here is another video from Topps capturing a glimpse of the manufacturing process once again.

I think it’s safe to assume that one manufacturing method used to cut cards is a cardboard slitting machine.  There is another method of cutting that I came across online.  Below is a video from Edis Packaging.  This is a company that manufactures trading cards for several different companies. 

You can see they’re producing a Topps set in the video.  Starting at the 0:27 mark you can see a different approach to cutting cards from sheets.  The machine shown holds a stack of card sheets in place and then drops a giant blade that comes down and slices through the stack of card sheets.  The blade moves a bit like a guillotine.  This process seems to be much more hands on, as you can see an employee handling the stack of card sheets throughout the process.  You can also see the name of the equipment manufacturer, Baumann, in the video.  Here is a link to a page that describes the guillotine cutter.  If you’re incredibly interested in the subject of cutters and print media, consider picking up the Handbook of Print Media.

So far we’ve established that there are at least a couple of manufacturing methods used for cutting sports cards.  Without some direct experience with each process, I can’t tell you the difference between how the edges of the cards will appear.  Unless you already have an example of a card from the same set, from a source you trust, it’s going to be hard to know if a card possesses the edge as created by the manufacturing equipment.  But, we may have another way.  Let’s look at using statistics and probability to determine how likely it is that a card has been trimmed.

I decided to take (50) 2018-19 Prizm Basketball base cards and measure the height and width of each card.  I used calipers to measure these characteristics on each card.  Calipers are often used by machinists when they need to measure things will high accuracy and precision.  I was able to measure these dimensions at a resolution of 1/100th of an inch (0.001”).  For reference, an average human hair is about 0.004” in diameter.  Once I collected these measurements, I calculated the average width and height of the cards.  I also calculated a value called the standard deviation for both the width and height.  For the purposes of this blog post, I’ll explain the standard deviation as a calculated value that quantifies how much the measurements were spread around the average.  For example, some cards measured wider than the average width and some measured smaller than the average width.  The degree to which the cards were larger or smaller than the average width is quantified by the standard deviation.  The standard deviation will turn out to be supremely important in this analysis, so I hope that it makes at least a little bit of sense to you.  Try watching this video if the concept is not a familiar one.

The data collected on these cards follows a normal distribution.  If statistics aren’t really your thing, you might still be familiar with the shape of the normal distribution.  It’s a bell curve.  The exact shape of the normal distribution can be described by the average and the standard deviation.  The smaller the standard deviation, the higher the bell curve peak is at the average and tighter or more narrow the curve is.  A larger standard deviation results in a shorter peak and a broader spread to the curve.  Below is a picture showing some example normal distribution shapes.  The peak of each curve represents the average value (mu).  The width of each curve is representative of the magnitude of the standard deviation squared (sigma).

Normal distribution example courtesy of  Wikipedia Commons .

Normal distribution example courtesy of Wikipedia Commons.

What’s really cool about a normal distribution is that it allows you to use the value of the standard deviation to predict the percentage of measurements that are expected to fall within a set of values.  For our example with the card measurements, we can expect 68.2% of all cards to have a width measurement somewhere between the average plus one standard deviation and the average minus one standard deviation. 


As we increase the range of card with to include plus or minus 2, 3, or 4 standard deviations, the percentage of cards with a width within those ranges can also be predicted.  Here are the formulas for those scenarios.


As you can see, by the time you get to plus or minus 4 standard deviations, we can predict that only 6 out of 100,000 cards will have a width outside that range.  It doesn’t mean that it’s impossible for a Prizm base card to come off the Panini process with a width greater or less than the 4 standard deviation limit, but it’s incredibly unlikely that you or I will come across it.  That fact is incredibly helpful.  If we can measure a card, we can compare it to these ranges.  Depending on the measurement we can decide for ourselves, based on probability alone, if it is likely that the card has been trimmed or not.  I have no idea how PSA or BGS goes about determining their minimum size requirements for grading a card.  If I were to start a card grading company I would use this method, with a bias toward refusing to grade a card if it wasn’t within a range somewhere around the plus or minus 3 standard deviation limits.

Card measurement data could also be supplied to collectors by manufacturers in the spirit of transparency.  I’m sure each manufacturer has a quality assurance department.  It’s very likely that each one has a set of calipers as well.  If only they measured a sampling of cards and made the data public to collectors.  It could give us more confidence that the cards we buy on the secondary market are not trimmed.

Below is the data I collected on the 2018-19 Prizm Basketball base cards. Remember, this data only applies to 2018-19 Prizm base cards. Do not use it for reference for other cards or sets.

Thanks for hanging in there with me so far.  I will be continuing this discussion soon in Part 2 of this blog post.

Till next time - Jeff

Cuts Like a Knife - Part 2

Cuts Like a Knife - Part 2

How is this possible?  2018-19 Optic Basketball Edition

How is this possible? 2018-19 Optic Basketball Edition