So your grub screw hex key is rounded and you have searched and tried the usual solutions and now it becomes apparent that you have to drill that grub screw out even with a drill mill this is a pain hard to clamp easy to damage well have no fear JoJoOne is here the JoJoOne Grub Screw Remover should help you remove that grub screw without damaging your motor, extruder gear or your hand It works by securing the motor and locking the shaft from rotating allowing you drill the screw center out. The grub screw remover is for geared type extruders although it could be adapted for other types I will include the Step files.
How to use the JoJo1 Grub Remover
Place stepper into the remover aligning the gears and grub screw to the drill guide slot and press into place it will be tight.
Secure motor with four bolts
To use with drill stand or mill there are clamping points on the side.
To use with hand drill there are four holes on the bottom to secure it to a bench.
Use appropriate drill size usual 2mm
The aim is to drill the centre of the grub screw out not the whole thing as this would damage the thread. Drill out the grub screw centre this should now allow you to slide the extruder gear of the motor shaft and will leave the remaining part of the grub screw loose this should be easy to remove from the gear with a torx driver.
JoJoOne Tip: small diameter drill bits need to be run at a higher rpm or they will snag and snap the use of some thread cutting oil helps.
Hope this helps you fellow inventor’s designers and makers out of a pickle as always Robojojo1 needs those likes to keep his operating system running gears lubed and motors tuned....... anyway
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