If you find that your prints are skewed when they should be square, your X-Y axis may not be perpendicular when looking from the Z direction. This block corrects that skew. It should be attached to the smooth rod locks that come with the printer. This mod, in combination with Z axis braces, sacrifices a few mm in the Y and Z direction to allow all 3 axes to be perpendicular to each other. Once installed, the Y axis belt will be rubbing against itself. Install the Y Bracket Extension to prevent the belts from rubbing each other and also from pulling the carriage plate down in the middle.
Parts required for each block:
- 4 M3 x 5mm bolts
- 2 M5 nuts (Nylon Lock Nuts are optional)
Parts required for Y Bracket Extension:
- Detach smooth rod locks from printer and remove them from the smooth rods
- Use 2 M3 bolts to attach the correction block to the rod locks. The head of the bolt should not protrude past the face of the correction block.
- Place the correction block back onto the smooth rods as shown in the example pictures.
- Use 2 M3 bolts and M3 nuts to attach the correction block to the printer frame as shown in the example pictures.
- Level and align the smooth rods.
Method to align smooth rods:
- Ensure smooth rod lock bolt and 2 correction block bolts are loose enough to allow shifting.
- Move the headed bed to the front of the printer and lightly tighten the 2 correction block bolts
- Move the headed bed to the back of the printer and lightly tighten the 2 correction block bolts
- Remove heated bed and carriage. Leave the linear bearings on the smooth rods.
- Place the smooth plate directly onto the smooth rods.
- Press down on each of the 4 corners of the plate, directly above the smooth rod. If there is movement, adjust the height of the correction blocks.
- Move the Z axis up
- Position the square above the smooth rods and place up against the X axis rods. Ensure that the bottom of the square is firm against the smooth plate or Y axis smooth rods.
- Use a piece of paper to test the gap between the square and the 2 X axis rods.
- Adjust the Z axis braces until the gap between the square and the 2 X axis rods are the same.
- Move the Z axis down
- When using a square similar to http://www.homedepot.com/p/Husky-Universal-Square-HUS125/203951642, place one of the shorter legs flat against the X axis rods. The long leg should be running parallel to the Y axis rods.
- Slide the correction blocks left or right until the Y axis smooth rods run parallel to the square.
- Use calipers to check that the space between the rods are the same along the rods. Check the spacing in the front and back of the printer. If the measurements are within 0.5mm of each other, the rods can be considered aligned.
- Recheck and/or reiterate the alignment process for better results.
- Ensure all bolts are tightened. Be careful not to strip the rod lock.
- Install the Y Bracket Extension to the carriage plate and Y axis belt belt bracket.