MK3 Style Y-Belt Holder for MK2, MK2.5

The original MK3 Y-Belt Holder and Y-Belt Tensioner allows users to dial in the belt tension, which is a feature not present with stock MK2 and MK2.5 Prusa printers. While the MK3 Y-Belt Holder and associated Tensioner will fit on a MK2 or MK2.5 printer, the Y-Belt Holder will not engage the limit switch at the rear of the machine. This redesigned MK3-style Y-Belt Holder resolves that issue.

Please note that you will need to download the original MK3 Y-Belt Tensioner part, which works in conjunction with this part to allow belt tension adjustment

Other hardware needed(Note: Same as original MK3 Y-Belt Holder and Tensioner):

• 4 M3x10mm Screws
• 3 M3 Hex Nuts
  • Note: Original MK3 assembly instructions call for one of these to be a lock nut. However, once you adjust the tension, the parts are locked into position using the M3x10 screws, preventing a premature loosening of the belt. If you would rather use a M3 lock nut here, feel free, but it's not necessary.
• 1 M3x30mm Screw

Assembly:

1. Insert nuts in associated nut traps
2. Loosely secure both the Y-Belt Holder and Y-Belt Tensioner to the Y-Carriage
3. Prepare belt by wrapping end of belt around M3x10mm screw with teeth facing inward.
   1. Note: Teeth should engage with one another a few mm.
4. Screw M3x10mm-wrapped screws into both Y-Belt Holder and Y-Belt Tensioner
   1. Note: Do not overtighten and deform the belt
   2. Note: Screw end should not protrude from bottom of either part. If so, the screw will hit the motor and prevent engagement with the limit switch.
5. After belt is in position, insert M3x30mm screw and tighten appropriately for proper belt tension.
   1. Note: Prusa's belt tension meter is a great tool to get your belt tension dialed in.
   2. Note: You may need to squeeze Y-Belt Holder and Y-Belt Tensioner together slightly to engage M3 nut and M3x30mm screw.
6. Once belt tension is dialed in, tighten M3x10mm carriage-mounting screws to fix both parts into position.

Print Settings:

• Filament: Nothing less than PETG with respect to temperature resistance. 
• Perimeters: 3 
• Infill: 20%