The blade holder when printed was loose on my Ultrasaber 24" blade so much there was a gap around the blade and the emitter would not tighten against the blade.
I modified the original Blade_Holder STL as well as the Blade_Holder (Short) STL to have an internal diameter of 25.4mm. This gave pretty much an interference fit against my blade and now the emitter locks the blade in place.
Hopefully if you find you have a slightly smaller diameter blade, these holders will help you out.
Update: It was pointed out that I had uyploaded both as 28mm tall versions, this has now been addressed. Thank you Mark Tomlinson for discovering my error.
The author remixed this model.
Replaced the shorter 28mm tall version and the 30mm tall version with tighter fit versions.