This guide is for users that have purchased the Ender 7 Bed Stability Upgrade from Tiny Machines 3D. 

We now offer the kit without linear rails so you can use your own or source them from another vendor.
You will need MGN12 single carriage in 390mm length.
If you purchased the kit without linear rails, note that the steel parts come unpainted. Thoroughly clean them with lacquer thinner or 99% isopropyl alcohol before painting them. We suggest a primer+paint combo like the following but you are welcome to be creative. Tag us on IG @tinymachines3d to show off your build! 

  • Krylon COLORmaxx  Spray Paint and Primer In One

  • Krylon Fusion All-In-One  Spray Paint and Primer In One


Installation

Tools Needed:

Metric hex keys (hex screwdrivers work )

  • M1.5, 2, 2.5, 3, 4, 5

M5.5 combination wrench OR M5.5 nut driver

  • Needle nose pliers can work (be careful)

Digital Dial Calipers or quality ruler


Idler Pulley Assembly 

Step 1 (AFTER REMOVING FACTORY Z AXIS COMPONENTS) 

 

2x Printed Spacer 7.5 mm (top)

2x Printed Spacer 4.5 mm (bottom)

Idler Holder

3x 5 mm Dowel Pin

6x F695-2RS  

6x 5×10×1 mm Shim


  • Assemble idler pulley stacks as shown in images above
    • Dowel pins should fit either way, but in some cases, we hand polished them. They should not require any force to fit inside the flanged bearings. 


Step 2


Idler Nut & Pin Holder

Top Idler Plate (Acrylic)

Bottom Idler Plate (Steel)

Tension Screw Bracket

2x M5 Hex Nut

2x M5x35 SHCS

2x M5 Flat Washer

2x Aluminum 22 mm Spacer

1x M4x14 SHCS


  1. Press M5 nuts into the printed part (idler nut+ pin holder)
  2. Insert pulley stacks from step 1 into bottom idler plate 
  3. Set the assembly on your work surface to make this easier
  4. Insert belt before putting on the acrylic top idler plate and fasteners
    • If you have any difficulty, try to pre-assemble the top plate with M5x35 SHCS, M5 washers, and aluminum spacers then attach to bottom idler plate with pulley stacks installed.

Lead Screw and Support Assembly

Step 3

Hardware need for both sides:

2x Pillow Bearing Nut Retainer

2x Leadscrew Bearing Mount

2x Pillow Bearing

4x M4x10 BHCS

4x M4 Flat Washer

4x M4 Hex nut


  • Build 2, identical sets of the lower bearing supports for the right and left lead screws
  • Leave the pillow bearing set screws loose

Step 4

  

Hardware need for both sides:

2x MGN12 Linear Rail 390mm

2x Linear Rail Alignment Jig

2x Linear Block Mount

16x M3 T-Nut

16x M3x8 SHCS

4x M3x10 SHCS

  • Linear rail is mounted with M3x8 SHCS and M3 T-nuts
    • Use the 2  Linear rail alignment jigs to hold the rail square to the 4040 extrusion
    • Rail sits flush at the bottom frame plate
  • Linear Rail Block Mount is mounted with 4 of M3x10 SHCS
    • Note the Threaded Inserts face up on both sides

Step 5


4x M5X25 SHCS

4x M5 Flat Washer


  • The Idler pulley assembly mount in front of the C-beam extrusion
    • Note, only take out the frame bolt needed to install the bracket to insure the frame stays in alignment
    • Leave belt tensioner screw loose

Step 6

A
B
 CD


4xM3x8 SHCS

4xM3 Tnuts

8x M5X25 SHCS

8x M5 Flat Washer

  • Do 1 side at at time. In this case, only take out the stock frame bolts on one side (See image A). Next, install the lead screw mounting plate on that same side before proceeding to the other side.
  • Use the top bearing support and lead screw (See images B, C) to align the pillow bearing at the bottom. Next, fully tighten the M4 mounting screws for the pillow bearing. Then loosen the M3 screws holding the top bearing support then slide bearing suport to the top of the aluminum extrusion.  
  • After the bearing are aligned, remove the lead screws for the printer and remove the bearing for the top supports bearing form printed mounts
  • Install the pulley 6 mm from the bottom of the lead screw 

Bed Gantry Install

Step 7



Custom Bed Support Plate

Factory Bed Tray – reused

6x M4x6 SHCS – reused 

4x M3x14 SHCS

6x M4 Flat Washer

8x M3 Split Lock Washers

4x M3 Nylock Hex Nut

  • Install the custom bed support to the factory bed tray 
  • Center the side support plate with the stock Z carriage plate center cutouts 
  • Install the flanged part of the leadscrew nut with a lock washer below the plate and above the flange
  • Fully tighten the Nylock nut and M3x14 SHCS then loosen 1.5 turns

Step 8


  • Install lead screws into the Z carriage
    • Anti-Backlash nut lower half needs to be partially started on the top of the lead screw before the lead screw  is threaded into the top half of the lead screw nut.
    • There should be little to no gap between the notch and tooth of the two halves of the lead screw nut. Do this for both sides. Then, thread the lead screw halfway up

Step 9


4xM4x10 BHCS – Leave loose till the end of the step

4x M4 Flat Washer



Belt Path