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reprap:anet:a8:coupler [2018/03/19 22:38] – [But my axis still wobbles!] 0scar | reprap:anet:a8:coupler [2019/01/03 08:16] (current) – [But my axis still wobbles!] cj_elec_tech | ||
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- | ====== | + | ====== |
{{: | {{: | ||
- | ===== Why should | + | ===== Why should |
Couplers connect the motor to the threaded rods that move your z-axis up and down. If the motor and the rod are not perfectly aligned, the rotation of the motor will apply force to the rod and push it into x and y direction. This leads to the so called **z-wobble** and slightly shifted layers. | Couplers connect the motor to the threaded rods that move your z-axis up and down. If the motor and the rod are not perfectly aligned, the rotation of the motor will apply force to the rod and push it into x and y direction. This leads to the so called **z-wobble** and slightly shifted layers. | ||
===== The correct installation ===== | ===== The correct installation ===== | ||
- | It's simple: The middle of the coupler must be flexible. So don't insert the rods until they touch each other, just insert the rods on both sides for **5mm**. They have to get in touch with the screws, but they dont need go in all the way. | + | It's simple: The middle of the coupler must be flexible. So don't insert the rods until they touch each other, just insert the rods on both sides **5mm**. They have to go just past the screws, but they don' |
A simple illustration: | A simple illustration: | ||
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{{: | {{: | ||
- | The green marks show how deep the rods should sit in the coupler. The red mark shows where they shall not pass. ;) | + | The green marks show how deep the rods should sit in the coupler. The red mark shows where they should |
- | ===== Apply your coupler ===== | + | ===== Tighten |
- | Remember to tighten the screws on the coupler | + | Remember to tighten the screws on the coupler |
^ ^ ^^^^ | ^ ^ ^^^^ | ||
- | |1 (first screw)|3(third screw)| | + | |1 (first screw)|3 (third screw)| |
- | |4(last screw)|2(second screw)| | + | |4 (last screw)|2 (second screw)| |
===== But my axis still wobbles! ===== | ===== But my axis still wobbles! ===== | ||
- | There are many reasons for unwanted movements. Take a look at the [[reprap: | + | There are many reasons for unwanted movements. |
+ | Take a look at the [[reprap: | ||
+ | |||
+ | Be aware of all the so-called anti z-wobble devices found - especially those that constrain the threaded rod at the top of the printer. | ||
+ | |||
+ | True anti z-wobble devices decouple x and y movement from z movement and/or take the spring movement out of the coupler by constraining the threaded rod at the bottom, above the coupler. |