Project Dashboard LulzBot Bio Syringe Pump Assembly & Testing Workflow

1 Gather Materials

  • 1x [EL-MT0063] NEMA 11 Standard Hybrid Stepper Motor
  • 1x [EL-SW0022] SWITCH BASIC SPDT 3A .110QC 125V
  • 3x [HD-BT0005] M3 x 10 Bolt, SHCS Black-Oxide
  • 3x HD-BT0119] Black Alloy Steel Flat-Head Socket Cap Screw, Class 10.9, M3 Size, 8mm Size, 8mm Length, .50mm Pitch
  • 2x [HD-BT0137] M3 x 8 Bolt, BHCS, Black-Oxide
  • 5x [HD-BT0157] Black-Oxide Class 12.9 Socket Head Cap Screw, Alloy Steel, M3 Thread, 8mm Length, 0.50mm Pitch
  • 4x [HD-BT0244] Black-Oxide, Alloy Steel, FHCS, M2 x 0.4mm Thread, 6mm Long
  • 3x [HD-BT0255] M2.5 x 14mm, SHCS, Black Oxide
  • 1x [HD-BT0259] M2 x 8mm Bolt, SHCS, Black-Oxide
  • 1x [HD-BU0051] iglideR G300 Sleeve Bearing, ID 6mm, OD 7mm, 12mm Long
  • 2x [HD-MS0470] Two side Rubber seal Bearing, 623-2RS, ABEC1 grade
  • 1x [HD-NT0359] Helix - Lead Nut, Standard, Inch Flanged 3/16" x 0.20
  • 1x [HD-RD0076] Leadscrew, 99mm, 3/16", Stainless Steel, 0.2" Lead, RH, 4 Start
  • 1x [HD-RD0077] AWM-06 smooth rod, 90mm
  • 3x [HD-WA0038] Black-Oxide 18-8 Steel Flat Washer, M3 Screw Size, 3.2mm ID, 7.0mm OD
  • 1x [PP-MP0252] Steel Worm Gear, 5mm Bore
  • 1x [PP-MP0253] Bronze Worm Wheel, 4mm Bore
  • 1x [PP-MP0277] Kangaroo Paw, Toolhead, Upper Bearing Holder
  • 1x [PP-MP0278] Kangaroo paw, Toolhead, Lower Bearing Holder
  • 1x [PP-MP0279] Kangaroo Paw, Toolhead, Motor Mount
  • 1x [PP-MP0280] Kangaroo Paw, Toolhead, Collar Mount Flange
  • 1x [PP-MP0281] Kangaroo Paw, Toolhead, Carriage
  • 1x [PP-GP0453] Syringe Collar Mount
  • 1x [PP-IS0121] Syringe Pump Cover, v2, with inserts, Kangaroo Paw
  • 1x [PP-IS0120] Syringe Pump Mount, v2, with inserts Kangaroo Paw
  • 1x [EL-HR0190] Kangaroopaw, Syringe pump Harness
  • 1x [HD-MS0058] Wire Tie, 8" Black, pk 1000

2 Attach Worm Wheel to Leadscrew

Slide the Bronze Worm Wheel [PP-MP0253] to the unthreaded portion of the Leadscrew [HD-RD0076] with the geared side towards the end of the Leadscrew.
Ensure the Worm Wheel is on the Leadscrew as fas as it will go; the top of the Worm Wheel should mate against the start of the Leadscrew threads. See photo

Torque the set screw of the Worm Wheel to the flat side of the Leadscrew to 2 in*lbs.

a) Slide the bronze worm gear onto the rod
Torque down the set screw

3 Assemble Syringe Pump Carriage

Start one Sleeve Bearing [HD-BU0051] in the hole of the Carriage [PP-MP0281] in the orientation shown.

Place the Carriage [PP-MP0281] flat side down on a flat portion of the arbor press working area.

Use the arbor press to slowly push the Sleeve Bearing into the Carriage until it bottoms on the arbor press plate. Do not compress the sleeve bearing further as it will mushroom the end and could cause additional drag.

Using two M3x8 BHCS [HD-BT0137], secure the Helix - Lead Nut [HD-NT0359] to the Carriage as shown.
Early builds use M3x10 BHCS HD-BT0148 with M3 Nuts HD-NT0004, production parts should have these holes threaded

a) Fit the sleeve bearing into the carriage
b) Place the carriage with sleeve on the arbor press
b) Carfully press the sleeve into the carriage
c) Assemble the carriage
c) Fasten the helix nut to the carriage

4 Install carriage to Leadscrew

Place the assembled carriage into the assembly jig as shown (only fits in one orientation).

Thread the end of the Leadscrew opposite the Worm Wheel into the Lead Nut of the Carriage until the Worm Wheel bottoms out in the jig.

a) Place the carriage next to the lead screw
b) Thread the lead screw throw the carriage
b) Continue threading the lead screw until its all the way down

5 Press bearings onto Leadscrew

At the arbor press, place the part/jig from the previous step into the working area of the arbor press with the bronze Worm Wheel facing up.
Ensure the Worm Wheel end is tightened into the jig by spinning it, before pressing bearings into place.

Place one bearing [HD-MS0470] on the end of the Leadscrew and use the arbor press to press it into place.
Visually inspect to ensure the bearing is fully seated on the end of the Leadscrew.

Rotate the jig in the arbor press working area so that the opposite end of the Leadscrew faces up.

Place one bearing [HD-MS0470] on the end of the Leadscrew and use the arbor press to press it into place.
Visually inspect to ensure the bearing is fully seated on the end of the Leadscrew.

Use the finger notch on the rear/bottom of the jig to eject the completed Leadscrew assembly.

a) Place the jig with the lead screw on the arbor press
b) Arrange the bearing on the jig as shown
b) Press down on the top bearing until it is in place
c) Flip the jig and place the second bearing on top
d) Press down until the bearing is in place

6 Install Upper and Lower Bearing Holder to Leadscrew assembly

Obtain one Upper Bearing Holder [PP-MP0277] and press it onto the bearing at the opposite end of the bronze Worm Wheel.

Slide one Smooth Rod [HD-RD0077] through the sleeve bearing of the Carriage and into the hole in the Upper Bearing Holder.

Obtain one Lower Bearing Holder [PP-MP0278] and press it onto the bearing at the Leadscrew end with the bronze Worm Wheel. Ensure the end of the smooth rod enters the hole in the lower bearing holder.

a) Place the upper bearing holder and slide the smooth rod through the carriage into the slot on the bearing holder
c) Place the lower bearing holder on to the assembly

7 Attach Motor Mount

Obtain one Motor Mount [PP-MP0279]

Using two M2x6 FHCS [HD-BT0244], attach the Upper Bearing Holder to the Motor Mount.
Before tightening, ensure the edges of the Upper Bearing Holder and Motor Mount mate flush and square.

Using two more M2x6 FHCS [HD-BT0244], attach the Lower Bearing Holder to the Motor Mount.

Torque all four fasteners to 2in\lbs

b) Fasten the upper bearing holder to the motor mount using 2x M2x6 FHCS
c) Fasten the lower bearing holder to the motor mount using 2x M2x6 FHCS

8 Attach Worm Gear to Nema 11 Motor & Lubricate

a) Obtain one Steel Worm Gear [PP-MP0252] and one NEMA 11 Motor [EL-MT0063]

Using the pulley spacer jig, attach the Steel Worm Gear to the shaft of the NEMA 11 Motor with the set screw towards the motor.

Torque the set screw against the flat side of the motor shaft to 2in*lbs

Place the Motor (w/ Worm Gear) on top of a paper towel.
Give a quick shot of White Lithium spray to one side of the Worm Gear and then rotate and apply another quick shot to the other side of the Worm Gear.

9 Attach Motor to Motor Mount

Obtain one Collar Mount Flange [PP-MP0280] and 3 M2.5x14 SHCS [HD-BT0255]

Orient the parts as shown
The motor's connector is facing down in the photo

Thread the M2x5x14 SHCS through the Collar Mount Flange and the Motor Mount, and into the threaded holes on the motor.

Apply pressure to the motor so that the Steel Worm Gear is pressed as close to the bronze Worm Wheel as possible and tighten the fasteners.

Torque all 3 fasteners to 3in*lbs

b) Orient the parts and fasten the 3x M2.5x5 SHCS to the motor
d) Apply pressure to the motor when tightening down the screws

10 Install Syringe Pump Mount

Obtain one Syringe Pump Mount w/ Inserts [PP-IS0120] and 3 M3x8 FHCS [HD-BT0119]

Place the Syringe Pump Mount w/ Inserts onto the bottom of the Collar Mount Flange as pictured.

Secure using the 3 M3x8 FHCS, torqued to 5in*lbs

Fasten the syringe pump mount using 3x M3x8 FHCS

11 Install Syringe Collar Mount

Obtain one Syringe Collar Mount and 3 M3x10 SHCS [HD-BT0005]

Place the Syringe Collar Mount on the Collar Mount Flange as pictured.

Secure using the 3 M3x10 SHCS, torqued to 5in*lbs

b) Place the syringe collar mount on the assembly as shown and secure using 3x M3x10SHCS

12 Install Enstop Switch and Syringe Pump Harness

Obtain one Endstop Switch [EL-SW0022], two M2x8 [HD-BT0259], and 1 Syringe Pump Harness [EL-HR0190]

Attach the Endstop Switch [EL-SW0022] to the assembly with the tab facing down and forward, using two M2x8 [HD-BT0259]
Torque to 2in*lbs

Attach the Syringe Pump Harness [EL-HR0190] to the Endstop Switch outer tabs.
Bend the Endstop Switch tabs in towards the Motor Mount.

b) Fasten the endstop switch to the assembly using 2x HD-BT0259
c) Attatch the syringe pump harness and route the wires as shown

13 Install Syringe Pump Cover

Obtain one Syringe Pump Cover w/ Inserts [PP-IS0121], five M3x8 SHCS [HD-BT0157], and three M3 Black Washers [HD-WA0038]

Route the Endstop Switch leads (purple wires) down between the two outer tabs of the switch and down the side of the motor mount, as shown in the photos.

Slide the Syringe Pump Cover onto the assembly

Secure the cover from below the collar mount using 2 M3x8 SHCS Secure from the rear using 3 M3x8 SHCS with washers Torque all 5 fasteners to 3in*lbs

b) Route the endstop wires as shown
c) Slide the syringe punp over the assembly
Secure using 5x M3x8 SHCS
Note that 2x M3x8 SHCS will be installed from the bottom of the collar mount

14 Connect Motor and apply Zip-tie

Obtain one Zip-tie [HD-MS0058]

Connect the small white connector of the Syringe Pump Harness to the NEMA 11 Motor.

Pulling the slack from the purple wires, apply one zip-tie around the motor leads and the endstop leads, as close to the corner of the Syringe Pump Cover, as shown.

Cut excess zip-tie flush with the latch.

Connect the motor and apply zip tie as shown

15 Testing

Attach the completed Syringe Pump Assembly [AS-TH0077] to the test stand by sliding the mount into the hanger.
Connect the extruder harness of the test stand to the Syringe Pump Harness of the completed assembly.

Power on the test stand and wait for it to boot
Once booted, select NO at the first prompt

Select Media and run "test-bio-syringe-pump.gcode"

The carriage of the syringe pump will move upwards to the limit switch, back down to the lower travel limit, and then re-home.
Observe the test to ensure both the upper and lower travel limits are reached without binding.

When a Syringe Pump binds, it should make a louder vibration or a sound similar to grinding.
If any high pitched squeaks are heard, ensure the worm gear and worm wheel are sufficiently lubricated.
Some disassembly may be required to apply additional lubricant.

Syringe pump test stand
The test is complete once the pump has re-homed
Plug the syringe pump into the test stand and turn on
Press no when prompted after turn on the test stand
Select the print from SD card
Select the test gcode
Hit print
The pump will start by homing to the top
Once it has reached the top it will start moving down to the bottom
Done! Take me home