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Star Wars: Lightsabers – A Guide To Weapons of The Force by Pablo Hidalgo

ANATOMY OF A LIGHTSABER notes of interest:
(NOTE:  This is the 2018 version, so this is a canon reference book.)

• A true lightsaber cannot be assembled by a machine, only those sensitive to the Force can construct one.
• “Once the energy is focused, it leaves the handle from a positively charged energy lens inside the blade emitter.  The beam is trapped inside an energy field created by the kyber crystal, which bends the beam back towards a negatively charged high-energy flux aperture in the emitter.  To an observer, it looks like the blade simply stops growing, but this loop of energy creates the lightsaber’s distinctive hum as well as the spinning effect in the blade’s movements, making the weapon difficult to control for those without training.”
• (This is probably what makes the blades so bouncy against each other, because they’re–as someone once described them–a bit like energy chainsaws, in the way that they’re a loop going around and around, rather than a steady beam.)
• “A lightsaber is an extention of a Jedi’s Force awareness.  Becasue Jedi let the Force guide their selection of the crystal, the vibration the crystal creates in the lightsaber blade helps Jedi center themselves and find balance in the Force.”
• MYTH:  Only a Jedi or a Sith can wield a lightsaber.
  FACT:  "Anyone could pick up a lightsaber and use it, but lightsabers are extremely difficult to wield. Those used to swinging solid swords often find using a weightless blade a challenge–one that can have dangerous consequences.  Only through rigorous training and enhanced senses through the Force can a Jedi use a lightsaber to its full potential.“
• “Training lightsabers emit low-intensity blades that cannot cut and are not lethal.  Contact with a training blade will only sting or numb an opponent; however these blades do convey an accurate sensation of holding a real lightsaber.”
• “Most lightsabers incorporate a pressure activation lever that causes it to power down if dropped.  They may also have a ‘lock’ switch that keeps the blade active, so a Jedi can throw a lightsaber some distance and guide its path through the Force.”
• “Beyond its use as a weapon or an instrument of meditation, a lightsaber is a practical tool.  Given enough time, a lightsaber can cut through most substances.  Even shield-rated blast doors will melt after extended exposure to a lightsaber blade, making it nearly impossible to imprison an armed Jedi Knight.  Most Jedi will not risk slicing through bulkhead walls or high-energy force fields, though, because cutting into such a powerful source could be explosive.”
• MYTH:  A lightsaber can cut through anything.  
  FACT:  The key to creating a solid weapon that can clash with a lightsaber blade is not the metal used in construction but rather the energy the metal conducts.  Energy transmitted across a metal blade or polearm can foritfy a weapon so it can block a lightsaber blade.  The electrostaffs of the MagnaGuard droids or the energized weapons of Supreme Leader Snoke’s Praetorian Guards, for example, pose a challenge to even trained lightsaber combatants.“
• “Standard lightsabers and water don’t mix.  While some protective measures do exist, such as flashback waterseals, lighting a lightsaber underwater can be a problem.  The weapon may boil the surrounding water, spinning turbulance and making it difficult to control.  Should a Jedi become submerged in water during the course of an assignment, he or she had best make sure the lightsaber is prepared for such a journey.”
• “A Jedi who loses a lightsaber often builds another.  In times of great need–such as the emergency of the Clone Wars–the Order kept replacement lightsabers for Jedi to use while they built a new one.”
• “Above all, Jedi must keep track of their lightsabers.  Should a lightsaber fall into the hands of an unpracticed or dishonorable person, it will almost always lead to tragedy.”