Hi guys,
Long time lurker, first time poster. I've got my own idea as to why the knurling may have been turned down on the glass eye...
I believe the reason the knurling was turned down, was simply because the saber became uncomfortable for the actors to wield during combat. To better illustrate my point, look closely at some of the screen shots of John and Daisy gripping the saber, and you'll notice that they both grip the hilt high. They're basically resting their top hand right under the glass eye (most likely due to the red button being the activation) and if they're taking constant hits during battle sequences, I've got to imagine that the knurling was digging into, and scraping the top of their thumbs, and quite possibly the webbing between their index finger and thumb. I'm sure the knurling could have possibly caused cuts/lacerations or burns on the actors hands. For example, at one point during the behind the scenes blu-ray, John Boyega mentions that Adam Driver was overly passionate and super intense during that forest battle. From what I've read, Adam is a big dude, so I bet his saber swings were hard and strong.
We already know that they utilized memory foam grips covered in textile due to the fact that the standard grips were too hard on the actors hands, so I think my theory makes some sense.
Thoughts?
PS: Take a look at this pic. Notice how Finn grips the saber - his hand literally rests right up under the glass eye.
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