Off-spot Pins
Older table-based pinsetters that pick up the pins between throws could malfunction if a pin were moved sideways when the ball is thrown, but remained standing. The pin would now be out of alignment with the setter pickup holes, and the table mechanism would collide with these misplaced pins. Failure of the device to detect pin drift can result in setter mechanism collision damage, pin crush damage, or lane damage from blunt force pressure of the setter pressing down on the misaligned pin.
If a pin had drifted but still managed to be picked up, older table pinsetters would simply realign the pin into the correct spot when placing it back onto the lane. This results in less than accurate gameplay since the table is changing the pin positions during the pickup process.
Regular table-style fully automated tenpin pinspotters from AMF and Brunswick, from their beginnings earlier in the 20th century, have been required by the United States Bowling Congress to be able to accurately re-spot "off-spot" pins that have been knocked out of position, sometimes up to 15 cm from the normal setting position, and then place them back onto the lane in the same location. If the pins are sufficiently out of position to not be pickable, the table will detect contact with the misplaced pin, and shut down the pinspotter to prevent mechanism damage.
String pinsetters generally do not have a mechanism to place pins back on the lane exactly where they were before, during the spare clearing. Since there is no table, collision damage is not possible with a string pinsetter, but they can suffer from string entanglement when the pins are being picked up, that prevents pins from aligning with the pickup holes.
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