Open Juniormunk opened 11 months ago
there is no clamping force called out for that screw, where are you getting a value that is being determined as a "proper calming force"
There is no value called out for "proper clamping force" but the fuse needs adequate pressure to have proper heat transfer. It also needs to hold tight so the screw doesn't vibrate loose.
please remember that the thermal fuse is a catastrophic safety device. having "proper heat transfer" is not critical. its not a thermistor that needs accurate temperature measurements. attaching to the heater pad with silicone is also a perfectly sufficient method.
the thermal fuse is there to pop if your bed is heating uncontrollably. it is a last line of defense so if it pops you are already in a position where you need to rebuild a significant portion of your ruined printer.
its meant to prevent the damage from spreading to the surrounding environment but a bed heating uncontrollably means you have a printer with MAJOR damage already
I do think that the next rev should add a washer. It will help spread out the load across the more fragile ceramic thermal fuse. Simple and easy protection for the end user.
No washer is shown in the drawing on page 142 for attaching the thermal fuse. If no washer is used you are very likely to destroy the thermal fuse with proper clamping force.