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18. Bowling Ball - Altering Surface
Altering the surface of a bowling ball by the use of abrasives while bowling in USBC competition is prohibited.
All bowling balls so altered must be removed from the competition. (See Chapter 7, Section 2, for additional information.)
NOTE: If it is shown the bowler had prior knowledge his/her actions were in violation of Rule 18, the game(s) in which the violation occurred is (are) subject to forfeiture. In addition, the bowler is subject to dismissal from the league and suspension of membership.
Competition is defined as the remainder of the current game and remaining game(s) in the series being bowled.
The use of approved cleaning agents such as isopropyl (rubbing) alcohol and polishing machines is permissible.
Commonly Asked Questions – Rule 18
18/1
When can an acceptable cleaner be used on a bowling ball?
Unless otherwise provided by league or tournament rule, cleaners designated as acceptable by USBC standards can be used on bowling balls at any time during USBC competition. For a complete list of acceptable cleaning agents, see bowl.com.
18/2
Can abrasives be used during certified competition?
The outer surface of any bowling ball cannot be altered with an abrasive after the start of competition. This includes balls that have not yet been introduced into play.
Further, the start of competition is defined as the point the first ball is thrown by any participant for score. This would allow a bowler to alter the outer surface of a ball during practice and not be in violation of Rule 18.
18/3
A tournament consists of doubles and singles events. The singles event is bowled first immediately followed by the doubles. Can I sand my bowling ball between events?
No, Rule 18 does not allow the outer surface of any bowling ball to be altered with an abrasive after the start of competition. This includes balls that have not yet been introduced into play.
The start of competition is defined as the point the first ball is thrown by any participant for score. Since the tournament is conducting singles and doubles concurrently, you cannot alter the surface of the bowling ball (including sanding) between events.
18/4
Can a bowler use an abrasive on just the track or just a portion of the track of the ball?
No. USBC specifications require that the entire surface of the ball be sanded in a uniform manner. Sanding a ball in any other manner would be a violation of Rule 17a, Item 1. The penalty for a violation of this rule can include disqualification, forfeiture, removal from the league, and/or suspension of USBC membership.