Bondtech LGX Lite eXtruder

The Bondtech LGX Lite is a filament feeder based on the LGX Large Gears eXtruder and uses Bondtech’s new Dual Drive Technology based on larger drive gears.

8 features of this Bondtech eXtruder:

• Larger drive wheels for increased filament grip
• Filament pre-tension lever for repeated results on rigid and flexible materials
• Drive wheels’ maintenance windows for easy cleaning
• Compact, light & centered filament path for increased performance and compatibility
• Multiple mounting hole patterns for an easy and flexible setup
• Compatible with Nema14 round stepper motors
• Craft boxes without bleaching & no coating
• Nylon housing with no dyeing or other chemical post-processing

Looking to use the LGX Lite with a Mosquito^® or Copperhead^® Hotend? Click here for the LGX Lite Mount.

Each Bondtech LGX Lite extruder is supplied with:

• 1x LGX Lite feeder;
• 1x LDO Nema14 Round 20mm pancake stepper motor;
• 1m long lead cable
• with JST-XH 4-pin connector
• 1x 2mm Hex Key (recommended tool);
• 1x Powered By Bondtech sticker.
• 1x Push-fit collar
• 1x 30mm PTFE tube to use in the PTFE Tube Adapter.
• 8x M3 square nuts for reinforcing mounting holes.

3D Printed Housing using PA12

The housing parts are professionally printed with polyamide 12 for maximum strength, precision, and higher temperature resistance.

• e-steps value : 562 using 16 microsteps; 1124 using 32 microsteps.
• Drive wheels : hardened steel;
• Materials compatibility : abrasive; rigid; semi-flexible; flexible; and soft.
• Mounting holes : M3
• Mounting patterns : bottom (4 points); right (2 points), front to motor (2 points), top (1 point)
• Hole at the top of the LGX Lite : 5 mm depth
• Holes on the side of the LGX Lite : 5 mm depth
• Holes on the bottom of the LGX Lite : 5 mm depth
• Max tightening torque on the extruder screws is 0.3 Nm

For Klipper users

rotation_distance = full_steps_per_rotation * microsteps / steps_per_mm

rotation_distance = 200 * 16 / 562
rotation_distance = 5.7

The above calculation assumes the following parameters:

• stepper motor is a 1.8 degrees motor, hence 200 as full steps per rotation;
• microsteps are set to 16;
• e-steps value recommended for the LGX Lite is 562.
• retraction speed : 35 mm/s
• retraction distance (bowden) : ~5 mm (0.4 + tube length[mm] x 0.015)
• retraction distance (direct drive) for rigid materials : 0.4 mm
• retraction distance (direct drive) for soft materials : 3 mm
• Max Environment operating temperature : 70°C
• Max stepper motor running temperature (using LGX Lite) : 80℃
• Recommended stepper motor current (using LGX Lite) : 0.45 to 0.60 A
• LGX Lite net weight : 48 g
• LGX® Lite with motor net weight : 141 g
• Package measurements : 80x103x73 mm
• Package weight : 85 or 185 g

How to change the Current using Vref

It is very hard to read the current being fed to stepper motors. To determine that current, we rely on the Vref value. The Vref value is a voltage reference measured in VDC that can be read using a multimeter. It helps us set the current output of the stepper motor driver.

Different 3D printer mainboards use different stepper motor drivers. Each type of stepper motor driver has its own formula to calculate the required Vref to get a specific current. Here are some examples:

• TMC stepper drivers.
  The formula for these drivers is Vref = ( I * 2.5 ) / Imax
  Where I is the target current value measured in A; and Imax is 1.77 on regular mode and 1.2 on SilentStepSticks mode.
• Pololu A4998.
  The formula for these drivers is Vref = I * 8 * R
  Where I is the target current value measured in A; and R is the Sense Resistor value, that depends on what board are you using. Melzis use 0.1,the Creality Silent boards use 0.15, ...

Mounting Patterns & Information
Extruder and Stepper Motor go together
Preferably, you should always use the extruder attached to the stepper motor when you mount it on a printer.

If you need to put a plate in between the stepper motor and the extruder please notice the max supported thickness is 3mm.

To use a plate in between the stepper motor and the extruder, you need to replace the stock rear plate of the extruder with the printer’s plate (thicknesses between 2 and 3mm).
Don’t use a plate in between without removing the rear plate.

MULTIPLE MOUNT PATTERNS
The LGX Lite features 4 mounting patterns:

1. 4 holes at the bottom;
2. 2 holes at the right hand side;
3. 1 hole at the top plus the filament entry that may be used as an anchor.
4. 2 holes across, to hold the stepper motor

All holes except for the frontal mounting holes on the LGX Lite require an M3 square nut inside the housing to act as reinforcement. The holes with square nuts have M3 threads and are 5 mm deep (until the bottom of the square nut).