Wobble Free Z-Axis Oldham Coupler and Hot-end Saver

thingiverse

This design effectively eliminates Z-axis wobble, and it did for me too. It also prevents damage to your hot-end, bed, or glass surface in the event of a z-axis sensor malfunction. First, let's get into the story behind this design. If you're not interested in knowing why I created this solution, just scroll down to "what" below. WHY: I was plagued by a Z-wobble problem and tried numerous solutions to fix it. I experimented with creating a tool for perfect alignment, adding bearings, moving the motor to the top or bottom, using different couplers, and even trying out a different lead screw. Initially, I bought a 1204 from Aliexpress that was too short due to its design flaw, but then I purchased a longer one only to find it arrived bent. I tried various designs, but they either were too big or didn't yield satisfactory results. The COVID-19 pandemic gave me some extra time on my hands, and I decided to fix an old BB gun from my childhood. After fixing it, I bought new BBs so I could test them out. The BBs are perfectly round, which led me to the idea of using them as bearing balls to create a "floating" platform for the Z-axis. It was perfect on the first try! This design effectively solved the Z-wobble issue, even with a bent or misaligned lead screw. Additionally, if you have problems with your Z-axis bottom sensor or limit switch, this design will prevent damage to your hot-end and glass surface. WHAT: To better understand the design, take a look at the drawing below. It consists of three platforms and two spherical layers. To build it, you'll need 24 BBs that are 4.5mm in diameter. These are extremely cheap, and even if you don't have a BB gun, I'm sure you'll find projects to use them for. I added a small amount of silicone grease to the BBs as well. You can purchase BBs on Amazon at an affordable price of $2.50. Here's the link: https://www.amazon.com/Daisy-Ammunition-count-tube-Blister/dp/B00279OFNA/ref=sr_1_1?dchild=1&keywords=bb+4.5mm&qid=1608847060&sr=8-1