Differences
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| Next revision | Previous revision | ||
| reprap:anet:a8:coupler [2016/11/24 21:08] – created vidschofelix | 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: | ||
| Line 11: | Line 11: | ||
| {{: | {{: | ||
| - | 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 |
| - | Remeber | + | Remember |
| ^ ^ ^^^^ | ^ ^ ^^^^ | ||
| - | |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: | ||
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| + | 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. Securing the top of the rod makes the rod statically indeterminate, | ||
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| + | 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. | ||