Bed Leveling Knobs with Double-Jam Locking Feature

These are yet another set of bed leveling knobs that I created for my Creality K2 Plus when upgrading to the R3men graphite bed.  The fasteners for the stock knobs have a different thread pitch so you're not able to reuse them with the longer fasteners that come with the bed.  And while there were plenty out there to choose from, I wanted something with a slightly larger diameter for finer adjustments.  I also wanted to use heat set inserts in lieu of nuts.  No technical reason, just a personal preference.

I designed these to M4x8mm heat set inserts.  I happen to use these Kadrick ones, because they had the design I was looking for, and they had the best price at the time.  I've had great success with them holding strong even when torqued very hard.  But, I'm sure any other inserts with the same diameter and similar geometry should work though.

I printed these on my Qidi Plus 4 using this PC, but any other high temp filament should work fine.  I wouldn't recommend PLA due to the proximity to the bed, but it may work if you have nothing else.

The only critical print settings are to ensure that there are a minimum of 4 walls where you're inserting the insert.  You can either have that as the base setting for the whole model, or add a cylinder modifier to the main models to increase the wall count locally.  This is what I did to shorten the print time and use less material.

I've included the .step and .3mf files so people can remix them as they wish.  Please let me know if there are any improvements that I should consider, and I'll look at incorporating them.