Position the rail connectors such that the rail does not tilt. Gently place eleven balls on the second rail while ensuring the rail does not tip over. Find the point where the rail tips over after adding the twelfth ball and glue the connector. The test for the hour rail will be the same as that of the 5-minute interval rail. Finally, test all the rails by placing eleven balls on the bottommost rail and the middle rail; and four balls on the topmost. Drop a single ball on the topmost rail and make observations. All of the balls should smoothly slide off of their rails.
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