‘Saber rattle’ or wobble or lightsaber hilt rattle is when some of the internal components of a lightsaber move around and make some noise. For example some Ultrasabers lightsaber will experience saber rattle because the LED module is not held in place with a retention screw. Some lightsabers also have loose, unsecured battery packs, which could also cause saber rattle. In the case of a loose battery pack, you can add some extra padding to minimize the rattling.
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One of the problems with saber rattle, aside from the annoying noise, is that loose components and wiring can become damaged over time. One of the best ways to prevent saber rattle is purchasing a lightsaber with a chassis or installing a chassis in your lightsaber. A chassis is a protective shell that encases the battery pack or other internal components.
Another way to avoid saber rattle is by looking for lightsabers that use a retention screw to hold the LED module in place. Some custom saber companies also use a retention screw to hold the battery pack in place (e.g. Sabertrio uses an LED retention screw and a battery pack retention screw).
Alternate Uses of ‘Saber Rattle’
There are at least two alternate definitions of saber rattle. Some DIYers have made lightsaber-shaped baby rattles, so a ‘saber rattle’ could refer to a baby rattle. Also, the term ‘saber rattling’ is a display or threat of military power.