The flag display in this video has a few more issues. Flagpoles have halyard for a reason. The halyard provides some tension release on the flags some flexibility. When the flags are chained to the pole, torque on the flags is often times very hard on the flag. All the pressure goes to the header of the flag. For normal winds, this is fine, but when the winds are 40 mph, the stress is great. When a flag is chained or bolted to the pole, it is more difficult to take the flags up or down. Adding a truck, halyard and cleat, gives you a more versatile system (safer) that is also easier on your flags. Even when you fly more than one.
Why are chain-stitch flags easier to make?
Chain-stitch is a process where the sewing is continuous. The alternative is lock-stitched where each thread is doubled back and lock stitched. On a chain-stitch flag, if one stitch breaks, the entire stripe will unravel (as in the video). When a stitch on a lock-stitch flag breaks, it does not effect the other stitches.
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