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Baseball Card Surgery: Rebuilt Corners Hard to Detect

Corner wear on a baseball card disappears when a card doctor has the right tools.

Determining whether you have a card with rebuilt corners is no easy task, but when YOU have the right tools, it’s possible.  It’s the latest in our series on altered sports cards.

2nd in a series

by Kevin Saucier

There is a considerable amount of legitimate concern among serious sports card collectors about cards exhibiting signs of rebuilt corners. It’s the attempt by a "card doctor" to add extra card stock to a corner that is worn or rounded from normal handling and age to dramatically increase the condition. It is safe to say that a rebuilding a corner and making it sharp can add great value to a card. Some are done well enough to get past the eye of even the most experienced professional grader and wind up being placed in a high grade holder.

Rebuilt corners are more than likely seen on vintage cards since they can carry a high value and are prone to corner wear. The process is especially dangerous because it is typically seen on rare and valuable cards and if done with skill, can be surprisingly difficult to detect, even by the best trained eye or card expert. It is also the alteration that is least likely to be dected by a collector because of the skill level required.

Under ambient light and normal conditions, the corner of the above card looks very ordinary. It is nearly impossible to see the added card stock.

How corners are rebuilt

A rounded corner has had some degree of paper loss; therefore to rebuild a corner this paper will need to be replaced. Typically there are three types of card doctoring methods used to accomplish this task but by no means is the list all-inclusive. These included corner replacement, inserting a plug or adding a home- made card stock. The idea seems preposterous but it’s being done; perhaps not on a wide scale but evidence exists that it can not only be done, but done well enough to fool most everyone.

This is a magnified picture showing a corner from another card attached to a card which has had the original corner cut and then removed. It illustrates the start of a corner being rebuilt.

Sometimes an entire corner from another card is not used but instead a small solid piece of a similar card, referred to as a “plug” is inserted. A reverse tapered plug is then attached with an adhesive and ground card stock or fibers used as a filler.

This corner has been cut and has a tapered notch. it is ready to have a reverse tapered plug attached.

The final method does not incorporate the use of a solid piece but has a corner rebuilt using a home-made card stock. Traditionally this will be seen on a card that has a minor degree of corner wear that does not require a large area to be rebuilt. This new card stock mixture is molded to the card to create a sharp and distinct corner, with individually placed fibers used as for reinforcement. The image below shows home-made card stock added to the back of a card to rebuild a corner.

As talented as a card surgeon might be, it’s possible to detect rebuilt corners. Regardless of the method used, the card examination for this alteration is the same. In addition to a halogen light and loupe, this inspection will require the use of a black light. If a rebuilt corner is not immediately noticeable the suspected corner will need to be studied very carefully and closely. As mentioned above, a corner that has been professionally rebuilt can be one of the most difficult alterations to identify. Also keep in mind more than one corner may be doctored in this way.

How to look for a rebuilt corner

Under a halogen light, inspect the card corner and corner surfaces for inconsistencies in color, uneven wear, stray, unattached fibers as well as small high and/or low spots. Using your loupe, examine the suspected corner(s) and look very closely for individual fibers that may have been used as an attachment. These fibers will be close to the corner and may appear to be separated, crossed, stacked or spread apart further than normal.

Look for any discolorations or off colors that may be present. Often the adhesive used will not dry perfectly clear or may pick up a small amount of dirt when being mixed leaving a slightly darker corner tip. On the other hand it may be lighter in color because the replacement corner, plug, filler or adhesive could not be perfectly matched to the altered card.

Hold the card close to a black light and look for corners that have a slight illumination. Most of the card may seem to be dull or dark when compared to a light glowing corner. If used, more modern cardstock, starches, and some adhesives may not show under a halogen light but will be more noticeable when held by a black light.

Since the corner may have been molded into shape, inspect the end surfaces for possible areas where too much or not enough filler was used. If the adhesive did not work effectively or has become old and worn tiny fibers may stick out from the edges or corner surface. A less valuable vintage card can be ground up into powder and used as filler. The area serviced by filler may, however, have a different texture when compared to the rest of the card.

Home-made added stock using the powder from a card that’s been ground up seems to be the most common type of filler used in rebuilding corners

Check the corners and edges leading up to the corners for lack of a natural tone. Since new material has been added to the card, it will more than likely look newer that the rest of the card edges. Rebuilt corners will need to be shaped in one way or another. The edges leading up to the corner will need to blend evenly as the corner is shaped. This will certainly lead to a loss of the cards natural color tone since fresh cardboard is being exposed.

With this alteration is not unusual to see an edge with a nice even tone gradually get lighter as it gets closer to the rebuilt area. The card corner and edge may also show a darker than normal tone if the adhesive or mixture picked up any dirt or oils during the shaping or drying process.

A dark color can be normal, but in this instance, when examined under magnification, there are unnatural individual fibers placed to reinforce the corner. A closer study of the corner and edges showed this to be added stock which was discolored. The value of this particular card had its value increased by several thousand dollars based on the improved condition. It, too, was graded.


About the writer: Kevin Saucier has been collecting sports cards since childhood. He started submitting cards to 3rd party authenticators ten years ago. Not unlike most advanced collectors he purchased a valuable card only to find out that it was trimmed. Vowing to never let this happen again he tried to learn everything he could about card alteration techniques. To understand ‘card doctoring’ he needed to become a card doctor, albeit an honest one. Once proficient, he started submitting his altered cards to various grading companies in an effort to test the limits. So far, none of them have been rejected.

He now alters cards in every conceivable way in an effort to educate collectors at all levels about the variety of techniques that can sometimes fool even the most experienced collectors and professional graders. Many advanced collectors and hobby insiders now consider Kevin to be one the top experts in identifying altered cards. His knowledge and opinion is frequently used by collectors across the nation to validate cards suspected of being doctored or of questionable authenticity.

You can read part one of his series "Can You Spot an Altered or Restored Baseball Card" by clicking here.


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