# Pulsar™ Pellet Extruder

# What's in the box

Item Quantity
Pulsar™ Pellets Extrusion System 1
Pulsar™ Heatcore 1
Pulsar™ Extrusion Screw 1
M10 Socket Head 1
M10 Washer 1
NEMA23 Stepper Motor 1
10A Solid State Relay (SSR) 3
Digital Stepper Motor Driver 1
Cable harness 1
Motor Cable 1
Dowel pins 2

# What you need

  • RTD-to-Digital Converter (commonly know as RTD Amplifier or PT100 Amplifier circuit). Pulsar™ is using PT100 for temperature sensing and you need a PT100 amplifier board to make them work with your printer controller board. Any amplifier circuit will work, as PT100 is pretty standard.
  • Liquid-Cooling system (if you're not using Dyze Design Liquid Cooling Kit). You can find the minimum specs in our liquid cooling section.
  • Automatic Pellet Feeding system (Optional). Pulsar™ can be fed with pellets by gravity but it was also designed to work with Dyze Design's automatic pellet feeding system. Contact us for more information or to purchase the system.

WARNING

The Pulsar™ was designed to be actively cooled by a water loop. If you try to use it without a liquid cooling loop, you will experience issues.

WARNING

Purge the Pulsar™ extruder once the print is done. Using the appropriate purge compound for the material you processed will increase the lifecycle of the extruder & prevent clogs and jams. See the procedure “Purging the Pulsar”

# Initial Assembly

To eliminate the risk of damage during transportation, the extrusion screw and Heatcore comes disassembled. Follow the procedure to have the machine ready for mounting.

What you need :

  • 7 mm Allen key or Screwdriver
  • 4 mm Allen Key or Screwdriver
  • 4 * M5 Socket Head Screw
  • M10 Socket Head Screw
  • M10 Washer
  • Extrusion Screw
  • Pulsar™ Pellet Extrusion System
  • Pulsar™ Heatcore
  • Protective Gloves
  1. Place the Pulsar™ Extrusion System on a table with the hopper facing up.
  2. Insert the Extrusion Screw spline first in the Pellet Extrusion System
  3. Secure the Extrusion Screw in place using the M10 Washer and Socket Head Screw
  4. Make sure the Extrusion Spline is properly inserted in the matching feature
  5. Slide the Pulsar™ Heatcore over the Extrusion Screw
  6. Secure the Heatcore in place using the four M5 screws

# Mounting

Mounting the Pulsar™ is done using 3 M5 screws with 2 dowel pins for accurate positioning. This ensures a robust assembly to your 3D printer or machinery.

  • Threaded holes : M5 x 0.80. Minimum thread engagement of 8 mm
  • Dowel Pins hole are 4.00 mm x 10.00 deep

Check out our drawing page to get the 3D STEP file. Design your bracket according to the available mounting options.

On the CAD file, consider the following references:

  • 4.20mm holes are M5.00 x 0.80 threaded holes
  • 4.00mm holes are reamed holes for dowels pins

Pulsar™ Mounting Example

# Wiring

# Solid State Relay

Each heater has its own solid state relay (SSR). Three SSR is provided with the Pulsar™ in the box.

The fuse is optional but strongly suggested. Each fuse should be rated according to the power rating:

  • Top heater, 500 Watts, 5A for 120VAC and 2.5A for 240VAC systems
  • Middle heater, 350 Watts, 3.5A for 120VAC and 1.75A for 240VAC systems
  • Nozzle heater, 250 Watts, 2.5A for 120VAC and 1.25A for 240VAC systems

Many pins can be used as the temperature output control. Your 3D Printer Controller (or motion controller) pins can be as below:

  • The standard extruder output (E0, E1, E2, etc). These are usually rated at the same voltage as your main power supply (12VDC or 24VDC).
  • Any available expansion pins. These can be determined by checking the 3D Printer Controller specification pins.

Please refer to the following diagram for wiring the Pulsar: Pulsar Wiring Scheme

# Backplate Add-On Connectors

The Pulsar™ has three extra connectors on the backplate. One is for fans, another one is for a Z probe (bed sensor) and the third is for the included capacitive sensor mounted on the side of the material inlet (used for pellets presence in the inlet).

Pulsar Backplate Connectors

# Fan Connector

The fan connector mates with a Molex Mini-Fit Jr. The mating housing part number is 469920210.

Pin 1 Pin 2
GND V+

# Bed Sensor Connector

The bed sensor connector mates with a Molex SL. The mating housing part number is 50579403.

Pin 1 Pin 2 Pin 3
Signal GND V+

# Capacitive Sensor Connector

The bed sensor connector mates with a Molex SL. The mating housing part number is 50579403.

Pin 1 Pin 2 Pin 3
Signal Gnd V+

The capacitive sensor is supplied with the Pulsar. It needs to be mounted and plugged in the backplate.

# Adjusting the sensor

The sensor is capacitive, meaning that it doesn’t need specific material to operate. However, different materials may need different sensor settings. Here's a few steps on how to adjust your sensor.

  • Power on the pellet feeding system without compressed air
  • The sensor needs to be screwed in place and be flush with the inside wall
  • Fill the hopper with material
  • Use a small flat screwdriver to turn counterclockwise the potentiometer. Stop when it doesn’t detect material anymore. It should open the solenoid valve and give a faulty alarm after a few seconds.
  • Make a half turn clockwise and your done!

# Stepper Driver

# Using your own stepper driver

It’s possible to use your own stepper driver. However, make sure it can drive the motor with the specifications below, especially the current. We won’t be able to offer adequate support if an insufficient stepper driver is used.

# Using the provided digital stepper motor driver

Connect the PULSE (STEP), DIR, and ENA between your motion controller and the stepper driver. Please refer to your motion controller manufacturer datasheet for proper connections and pin locations.

WARNING

Do not connect the power output from a stepper driver into the signal input from our provided stepper driver.

ENA is optional. Stepper will be always active when open.

Apply power through V+ and V- according to the stepper driver specifications. Stepper windings should be connected to A+, A-, B+, B-. Colors are usually as follows: Black, Green, Red, Blue.

Check the micro-stepping and current configuration. Current should be set at 2.7A RMS and stepping should be set at 3200 pulses/revolutions (Equivalent to 16 micro-steps).

SW1 SW2 SW3 SW4 SW5 SW6 SW7 SW8
ON ON OFF ON ON ON OFF ON

# Liquid cooling

The Pulsar™ is actively cooled by a water loop. Cooled parts are made from aluminum alloy, thus an aluminum radiator is required to prevent galvanic corrosion. Please check our liquid cooling (opens new window) section for more details.

# Part cooling

For part cooling, you can either design your own fan duct or you can take advantage of the integrated cooling shroud near the nozzle tip.

Each hole is about 3.2mm diameter.

Pulsar's integrated cooling shroud drawing

# How to use

The cooling shroud is intended to work with compressed air. You can plug the air compressor tubing in the Pneumatic Push-In fitting at the back of the heatcore.

A 20-30 PSI air compressor should be enough to cool your printed parts.

Pulsar's Pneumatic Push-In fitting for compressed air

# Using the cooling shroud with your printer board

If you want your 3d printer board to control the air supply, you will have to use a solenoid valve with a power mosfet and plug the relay signal in the FAN input of your 3d printer controller board.

Please refer to the following diagram for connecting the cooling shroud:

Typhoon's integrated cooling shroud schematic

# 3D Printer Guideline

The Pulsar™ is a lot longer to most extruder for FDM applications. It is imperative you follow the following guidelines to ensure a safe approach to limit potential damages to your Pulsar™ extruder & printer.

# Retraction

While in operation, the screw of the pellet extruder must turn exclusively counterclockwise. Retraction must not be used. Turning the screw clockwise will lift melted material in unwanted zones where it can clog the flow. There’s an anti-oozing feature that will prevent oozing from happening.

# General

Printing without cooling is only possible with large parts. Thick and large layers take time to cool down, thus requiring you to reduce speed for small parts.

Z homing must be done very carefully due to thermal expansion. For bed leveling with a cold extruder, make sure you compensate the thermal expansion:

  • 0.32mm @ 200°C
  • 0.49mm @ 300°C
  • 0.66mm @ 400°C

# Use Z lift

Raising the Z axis between each fast-travel is required. It will prevent any collision with the printed part. See the Slicer section for more info.

# Consider thermal expansion

It’s critical to consider the heat cylinder thermal expansion when doing the bed leveling. For example, if leveling at room temperature, the printing head will be 0.25mm lower. See the General topic to learn more.

# Robotic Arm Guideline

If you plan on installing the Pulsar™ on a robotic Arm, you'll need to get some extra hardware to get the same features as a 3D printer controller. These items are the following:

  • A motion planner capable of outputting STEP / DIR pulses for the stepper driver.
  • Three (3) temperature controllers capable of working with PT100 temperature sensors. Their output will drive a SSR.

# Firmware

# Marlin Firmware

2.0.x

# Configuration.h

Set number of extruders:

#define EXTRUDERS 3

Set the correct temperature sensor values. Please refer to Marlin thermal settings (opens new window) to find the correct value based on your amplifier circuit.

#define TEMP_SENSOR_0 -5
#define TEMP_SENSOR_1 -5
#define TEMP_SENSOR_2 -5

Set temperature min temp:

#define HEATER_0_MINTEMP 19
#define HEATER_1_MINTEMP 19
#define HEATER_2_MINTEMP 19

Set temperature max temp:

#define HEATER_0_MAXTEMP 485
#define HEATER_1_MAXTEMP 485
#define HEATER_2_MAXTEMP 485

The heaters are very powerful, which is required for engineering and advanced polymers. If you are planning on printing low temperature, reduce the bang_max from 255 to 127.

Set temperature bang_max:

#define BANG_MAX 127

Increase the PID_functional_range:

#define PID_FUNCTIONAL_RANGE 100

Set the base PID values:

 #define DEFAULT_Kp 23.1
 #define DEFAULT_Ki 0.039
 #define DEFAULT_Kd 157.8

WARNING

Please perform a PID autotune for each heating element. Values may vary depending on the heater’s environment.

Set the extruder steps per mm:

#define DEFAULT_AXIS_STEPS_PER_UNIT   { XXX.XX, XXX.XX, XXX.XX, 224.6 }

Note: {X Axis, Y Axis, Z Axis, E Axis} The value of the XYZ axis may vary and are shown as XXX.XX

Set the max feed rate:

#define DEFAULT_MAX_FEEDRATE          { XXX, XXX, XXX, 150 }

Note: {X Axis, Y Axis, Z Axis, E Axis} The value of the XYZ axis may vary and are shown as XXX.XX

INFO

The feed rate is capped at 150 mm/s. Although the Pulsar isn’t fed a filament, we use a combination of a step/mm coupled with a configuration on slicers (see slicer section) to convert the RPM of the extruder into mm/s.

The following equation gives the RPM of the motor :
Motor RPM Equation

Switch enable logic for the extruder motor:

#define E_ENABLE_ON 1

# Configuration_adv.h

Configure the external stepper driver

#define MINIMUM_STEPPER_POST_DIR_DELAY 500
#define MINIMUM_STEPPER_PRE_DIR_DELAY 500
#define MINIMUM_STEPPER_PULSE 3
#define MAXIMUM_STEPPER_RATE 200000

# RepRap Firmware

TIP

In your configuration file, you should find values similar to the ones below. However, we do recommend that you use the online ReRap Firmware configurator tool (opens new window).

WARNING

The following information is based on Duet 2 and RepRap Firmware 3.x. We strongly suggest that you also read the official Duet/RepRap documentation (opens new window) to make sure you correctly connected and configured your Duet board, pt100 (RTD) amplifier board and RepRap firmware version.

# Config.g

Set the correct temperature sensor values. Please refer to Duet documentation to find the correct value based on your amplifier circuit.

M308 S1 P"spi.cs1" Y"rtd-max31865"    		 	; configure sensor 1 as PT100 on pin e0temp
M308 S2 P"spi.cs2" Y"rtd-max31865"             ; configure sensor 2 as PT100 on pin e1temp
M308 S3 P"spi.cs3" Y"rtd-max31865"             ; configure sensor 3 as PT100 on pin e2temp

Set temperature max temp:

M143 H0 S480
M143 H1 S480
M143 H2 S480

Set the extruder steps per mm:

M92 XXXX.X YXXX.X ZXXX.X E224.6

Set the max feed rate:

M203 XXXXX YXXXX ZXXXX E9000

INFO

The feed rate is capped at 9000 mm/min. Although the Pulsar isn’t fed a filament, we use a combination of a step/mm coupled with a configuration on slicers (see slicer section) to convert the RPM of the extruder into mm/s.

The following equation gives the RPM of the motor :
Motor RPM Equation

Assign heaters 1, 2 and 3 to the same tool:

M563 P0 D0 H1:2:3 S"Pulsar"

Configure external stepper drivers:

M569 PXXX SXXX R1 T3:3:5:0

The heaters are very powerful, which is required for engineering and advanced polymers. If you are planning on printing low temperature, reduce the maximum PWM by 50%.

Set maximum PWM (Change HX by H0, H1, H2, etc. Based on your heater configuration):

M307 HX S0.50

# Repetier Firmware

TIP

In your configuration file, you should find values similar to the ones below. However, we do recommend that you use the online Repetier Firmware configurator tool (opens new window).

# Configuration.h

Set the correct temperature sensor values. Please refer to Repetier configurator tool (opens new window) to find the correct value based on your PT100 amplifier circuit.

#define EXT0_TEMPSENSOR_TYPE 13
#define EXT1_TEMPSENSOR_TYPE 13
#define EXT2_TEMPSENSOR_TYPE 13

Set minimum temperature:

#define MIN_DEFECT_TEMPERATURE 20

Set maximum temperature:

#define MAXTEMP 500
#define MAX_DEFECT_TEMPERATURE 505

The heaters are very powerful, which is required for engineering and advanced polymers. If you are planning on printing low temperature, reduce the bang_max from 255 to 127.

Set maximum power output:

#define EXT0_PID_MAX 127
#define EXT1_PID_MAX 127
#define EXT2_PID_MAX 127

Set the extruder steps per mm:

#define EXT0_STEPS_PER_MM 224.6

Set the max feed rate:

#define EXT0_MAX_FEEDRATE 150

INFO

The feed rate is capped at 150 mm/s. Although the Pulsar isn’t fed a filament, we use a combination of a step/mm coupled with a configuration on slicers (see slicer section) to convert the RPM of the extruder into mm/s.

The following equation gives the RPM of the motor :
Motor RPM Equation

Switch enable logic for the extruder motor:

#define EXT0_ENABLE_ON 1

# Configuration_adv.h

Configure the external stepper driver

#define STEPPER_HIGH_DELAY 3
#define DIRECTION_DELAY 5

# Slicer

  • Set vertical lift to at least your layer thickness. For layers of 1.00mm, lift 1.00mm. Slicers aren’t yet optimized for large prints. Many over-extruded sections will be noticeable. Lifting the head will prevent any collision with the printed part.

  • Wipe nozzle to at least the line width. For a line width of 3.50mm, wipe 3.50mm or greater.

  • Set the heating to all heaters to the required temperature.

  • Set end script to turn off the three heaters in the extruder:

M104 T0 S0 ; turn off extruder
M104 T1 S0 ; turn off extruder
M104 T2 S0 ; turn off extruder
  • Output flow and pressure greatly changed depending on the printing speed. To get the best result, keep the output flow steady by keeping the same speed everywhere.

  • Change the filament setting to 2.85 mm. The Pulsar’s step/mm was calculated using the area of a 2.85 mm filament. You will notice an exaggerated over extrusion with 1.75 mm filament in the slicer’s settings.

  • Never use retraction with the Pulsar. The pressure generating screw cannot work in the opposite direction.

  • The theoretical maximum speed for the screw is 60 RPM. This speed is for an empty screw. Filled with polymer, maximum RPM should be below 50 RPM.

# Maintenance

# Gears

  • The gear should be greased through the two greasing ports accessible from top. Let the motor run freely while gently applying grease.

  • We suggest using white lithium grease. The Pulsar comes pre-greased with white lithium grease, ISO Viscosity Grade of 150.

  • We suggest using a small sized grease gun such as the Astro Mini Grease Gun.

# Bearings

The roller bearing needs to be periodically greased. To do so, it requires removing the top cover. The bearing is in two parts. Apply grease on the outer race & re-assemble the top cover. Between 5 - 10 grams of grease is enough.

See below chart for bearing greasing frequency :

Operating temperature (°C) Grease frequency (hr
< 50 2500
50 < OT < 80 1250
80 < OT 450

# Purging the Pulsar

Purging the extruder’s screw will be necessary in order to change material, perform maintenance on the system or decommission the extruder for more than a few hours. First thing should be to find the best purging agent for your application.

# Tools required

  • Purge material
  • Recycling bucket
  • Waste bucket
  • Allen Key
  • Vacuum
  • Funnel
  1. Bring your extruder to a high Z point
  2. Place the recycling bucket beneath the extruder
  3. Disconnect the automatic feeding system
  4. Disconnect the hoses and collect the remaining material in the bucket
  5. Vacuum the remaining pellets in the inlet
  6. Extrude the maximum of plastic using your normal print settings
  7. Stop extruding
  8. Using the funnel, fill the hopper with purge material
  9. Replace the bucket with the waste bucket
  10. Extrude purge material until it comes out clean
  11. Re-attach the feeding system (Stop here if you are decommissioning the unit)
  12. Feed new material in the extruder
  13. Extrude until the new material comes clean

# Swap Nozzle

WARNING

There’s some disassembly required to change the nozzle on the Pulsar™ extruder. It requires proximity to high voltage components. Security measure must be put in place and followed rigorously to perform the following actions.

# Tools required

  • 2 mm Allen Drive
  • 2.5 mm Allen Drive
  • 27 mm Hexagonal Key
  • 18 mm Hexagonal socket
  • Torque Wrench
  1. Bring the Pulsar Extruder to at least 150 mm from the bed and accessible by hand
  2. Hit emergency stop mushroom
  3. Make sure the Hotzone temperature is below 45°C
  4. Depressurize the cooling shroud line
  5. Unplug the 6 mm air hose
  6. Unscrew the 1 screw on the shield attached to the bottom bracket using the 2 mm Allen key
  7. Unscrew the 2 screws on the backplate attached to the bottom bracket using the 2.5 mm Allen key
  8. Remove the bottom bracket
  9. Secure the Barrel with the 27 mm Wrench
  10. Unscrew the Nozzle
  11. Clean the nozzle seat if needed
  12. Screw the new Nozzle in place
  13. Torque to 70 N*m
  14. Reinstall bottom bracket
  15. Reinstall air hose
  16. Reset the emergency stop
  17. Perform Z leveling

# Removing the Screw

Coming soon.

Last Updated: 8/20/2021, 8:09:38 PM