WHITE PAPER
Formlabs Logo

Replacing the Fuse 1 air heater

Replacing the Fuse 1 air heater

The Fuse 1 uses multiple heaters to bring the powder up to the proper temperature for sintering. A faulty or malfunctioning heater will prevent the printer from working properly.

Use this guide to replace the air heater on a Fuse 1 printer. To replace this component on a Fuse 1+ 30W printer, see Replacing the Fuse 1+ 30W air heater.

Fuse 1 air heater

Required supplies:

Formlabs:

  • Replacement air heater
    • 120 V: RP-FS1-120-AHTR-01
    • 230 V: RP-FS1-230-AHTR-01

Third-party:

  • 2 mm hex driver (flat-end)
  • 2.5 mm hex driver (flat-end)
  • 3 mm hex driver (flat-end)
  • 6.5 mm slotted screwdriver
  • Telescoping magnet wand
  • Utility knife
  • Flush cutters
  • Wire strippers
  • Bulb blower
  • Safety glasses
  • Tweezers (optional)
  • Nonreactive nitrile gloves
  • N95 or better respirator
  • 100 mm (4 in) foil tape
  • Spade crimping tool (example: DigiKey PN: 1742-3005CR-ND)

Estimated time: 45–60 minutes

Danger:

Read and follow all safety instructions and warnings in the operator manual. Replacement with incorrect parts can lead to burns, shock, fire, or explosion. Dispose of all parts in accordance with local regulations.

Warning:

Do not perform this procedure if the printer was printing less than six hours prior. Failure to do so may result in serious burns. Allow the print enclosure to cool to room temperature before touching or inspecting any Fuse 1 components.

Preparing the workspace

Overview: Prepare the printer and a dust-free workspace for replacing the air heater.

Notice:

Fuse 1 generation printers contain sensitive electronic components. Ground yourself before touching any electronics in the printer by using a grounding strap or touching a grounded piece of metal.

Step 1: Prepare the workspace

Clear a workspace around your printer. Ensure that the workspace is well-ventilated and free of dust.

Step 2: Unplug the printer

Disconnect the power cable before continuing with maintenance. Do not perform maintenance on the printer while it is connected to power. Wait five minutes after disconnecting the printer from power before proceeding.

Danger:

Performing maintenance on the printer while it is plugged in increases the risk of electric shock. Never remove the back panel of the printer while the printer is plugged in. Never reconnect the printer to power while the back panel is uninstalled.

Step 3: Remove the Wi-Fi antenna

Unscrew and remove the Wi-Fi antenna, if it is connected.

Removing the rear panels

Overview: Remove the rear panels to access the interior of the printer.

Step 1: Remove the lower rear panel screws

The six black lower rear panel screws are circled in red. The four chrome lower rear panel grounding screws are circled in blue.

Using a 2.5 mm hex driver, remove the six black panel screws and the four chrome panel grounding screws securing the lower rear panel to the printer. Set the screws aside, taking care to separate the black and chrome screws for later reinstallation.

Step 2: Remove the lower rear panel from the printer

Pull the lower rear panel straight back and away from the printer. Lay it down on a flat, clean surface.

Step 1: Remove the lower rear panel screws

Step 3: Locate the exhaust duct and ring clamp

Locate the ring clamp attached to the exhaust duct in the center of the printer.

Step 4: Loosen the ring clamp screw

Using a 6.5 mm flathead screwdriver, loosen the ring clamp screw. Do not remove the screw. Pull the exhaust duct away from the exhaust pipe.

Step 3: Locate the exhaust duct and ring clamp

Step 5: Locate the exhaust inlet

Open the filter cabinet door on the printer. Locate the exhaust inlet on the right side of the cabinet.

Step 5: Locate the exhaust inlet

Step 6: Remove the exhaust inlet screws

Using a 2.0 mm hex driver, remove the four screws attaching the exhaust inlet to the filter cabinet. Set the screws aside.

Step 6: Remove the exhaust inlet screws

Step 7: Remove the upper rear panel screws

The two black upper rear panel screws are circled in red. The two chrome upper rear panel grounding screws are circled in blue.

Using a 2.5 mm hex driver, remove the two black panel screws and two chrome panel grounding screws securing the upper rear panel to the printer. Set the screws aside, taking care to separate the black and chrome screws for later reinstallation.

Step 7: Remove the upper rear panel screws

Step 8: Remove the upper rear panel screws

Using a 2.5 mm hex driver, remove the eight screws securing the upper rear panel to the printer:

Step 8: Remove the upper rear panel screws
Step 8: Remove the upper rear panel screws
Step 8: Remove the upper rear panel screws
  • Two 6 mm screws on the buffer side of the printer
  • Four 6 mm screws on the top of the printer
  • Two 6 mm screws on the hopper side of the printer

Set the screws aside.

Step 9: Remove the upper rear panel

Pull the upper rear panel straight back and away from the printer. Lay it down on a flat, clean surface.

Removing the top panel

Overview: Remove the top panel to access the interior of the printer.

Step 1: Remove the top panel screws

Using a 2.5 mm hex driver, remove the 18 6 mm M4 countersunk screws securing the top panel to the printer:

Remove the top enclosure panel
Remove the top enclosure panel
Remove the top enclosure panel
  • Four 6 mm screws on the front end of the buffer-side
  • Eight 6 mm screws on top of the printer
  • Six 6 mm screws on the hopper-side

Set the screws aside.

Step 2: Remove the top panel

Lift the top panel off of the printer by grabbing the IR sensor door and the rear-most edge. Set the top panel aside.

Removing the buffer-side panel

Overview: Remove the buffer-side panel to access the interior of the printer.

Step 1: Remove the buffer-side panel screws

Using a 2.5 mm hex driver, remove the four 6 mm M4 countersunk screws that secure the buffer-side panel to the printer.

Step 2: Remove the buffer-side panel

Separate the buffer-side panel from the printer and set it aside.

Remove the buffer-side enclosure panel

Removing the insulation and inner rear panels

Overview: Uninstall the internal insulation covering the air heater.

Step 1: Loosen the air duct ring clamp

If you have not already, put on a N95 or better respirator, a pair of safety glasses and a pair of nonreactive nitrile gloves. Use a 6.5 mm slotted screwdriver to loosen, but do not remove, the ring clamp screw securing the duct to the air heater inlet.

Step 2: Separate the air duct from the air heater inlet

Slide the duct off of the inlet. Gently move it away from the rear insulation panel.

Step 3: Open the insulation retention tabs

Straighten the three metal retention tabs securing the rear upper insulation panel.

Remove the insulation and inner rear panels
Remove the insulation and inner rear panels

Notice:

Ensure that both halves of each tab are parallel to each other. If they are not, they will shred the insulation as the panel is removed.

Remove the insulation and inner rear panels
Remove the insulation and inner rear panels

Step 4: Cut the insulation foil tape

Remove the insulation and inner rear panels
Remove the insulation and inner rear panels
Remove the insulation and inner rear panels

Feel along the insulation for the seams identified in the above image. Use a utility knife to cut along these seams and release the insulation panel.

Note:

You only need to cut through the foil tape securing the insulation panel in place; the insulation itself is already cut to size.

Alternatively, locate an edge of the existing foil tape and begin peeling it away from the insulation panel. It will still be necessary to cut the top corner pieces of foil tape in order to separate the panel from the printer.

Remove the insulation and inner rear panels
Remove the insulation and inner rear panels

Step 5: Remove the insulation panel

Carefully pull the insulation panel away from the printer.

Remove the insulation and inner rear panels

Notice:

Avoid abruptly removing the insulation panel, as it may begin flaking apart.

Step 6: Remove the inner rear panel screws

Use a 3 mm hex driver to remove the 13 8.0 mm M4 socket head screws that secure the inner rear panel to the printer.

Step 7: Separate the inner rear panel from the printer

Use a 6.5 mm slotted screwdriver to separate a corner of the inner rear panel from the inner back plate. Ensure that the driver is inserted between the gasket and second black steel plate.

Remove the insulation and inner rear panels
Remove the insulation and inner rear panels

Notice:

Avoid gouging the gasket as much as possible. If it is damaged, it will need to be replaced.

Step 8: Remove the inner rear panel

Continue separating the inner rear panel from the inner back plate without using the slotted screwdriver. Set the inner rear panel aside on a flat, clean surface with the gasket facing up.

Remove the insulation and inner rear panels

Notice:

Ensure that debris from the insulation panels does not become embedded into the gasket, as this can prevent it from sealing properly when replaced replaced. Depending on when the printer was built, the gasket may be made of a white or black foam material.

Remove the insulation and inner rear panels
Remove the insulation and inner rear panels

Removing the air heater assembly

Overview: Remove the original air heater from the printer.

Step 1: Disconnect the air heater wires

Locate and disconnect the two blue spade connectors that are connected to the harness labeled C003 AIR, located on the buffer side of the printer.

Remove the original air heater assembly

Step 2: Cut the air heater wires to remove the spade connectors

Cut both sets of cables at the base of each blue connector.

Remove the original air heater assembly

Step 3: Feed the air heater wires through the printer frame

Pull the air heater wires back through the silicone grommet to free them from the printer’s frame.

Remove the original air heater assembly

Step 4: Remove the air heater screws

Remove the original air heater assembly
Remove the original air heater assembly

Use a 2 mm hex driver to remove the four 6 mm M3 button screws securing the air heater assembly to the printer frame. Do not use a ball-end hex driver, as it will strip these screws. Only use a flat-end hex driver.

Tip:

Use a telescoping magnet wand to catch the screws once they are unthreaded.

Step 5: Remove the air heater

Remove the original air heater assembly and set it aside for disposal.

Installing the replacement air heater assembly

Overview: After removing the air heater assembly from the printer, install the replacement air heater assembly.

Step 1: Check the air heater gasket

Install the new air heater assembly - Gasket Check 1
Install the new air heater assembly - Gasket Check 2

Put on a pair of clean nitrile gloves. Check that both the gasket around the heater assembly and the heater fins are clean.

Use a bulb blower to dust off any insulation or contaminants from the air heater assembly. Do not touch the heater fins or the insulation with bare skin. If any insulation is pressed in between any of the fins, use a pair of tweezers to extract it.

Step 2: Align the air heater

Align the new air heater assembly with the corresponding screw holes on the back of the printer. Orient the air heater with its wires extending towards the buffer side of the printer.

Step 3: Secure the air heater

Install the new air heater assembly - Securing 1
Install the new air heater assembly - Securing 2

Thread one 6 mm M3 button screw into each of the four screw holes in the air heater. Using a flat-end 2 mm hex driver, tighten until snug. Do not use a ball-end hex driver, as it will strip these screws.

Step 4: Feed the air heater wires through the printer frame

Route the new air heater wires back through the red silicone grommet out to the buffer side of the printer. Pull any remaining wire slack out.

Install the new air heater assembly - Routing Wires

Step 5: Strip and prepare the air heater wires

Install the new air heater assembly - Stripping 1
Install the new air heater assembly - Stripping 2

Use an 18 AWG (stranded) wire stripper to remove roughly 1.0 cm (0.4 in) of insulation from each of the black and red air heater wires. Twist the black wire conductors together. Separately, twist the red wire conductors together. Ensure there are no fraying conductor strands.

Step 6: Crimp new connectors onto the air heater wires

Install the new air heater assembly - Crimping 1
Install the new air heater assembly - Crimping 2

Insert each twisted set of wires into a new spade connector. Ensure that the conductors are not exposed and the cables are inserted so the insulation butts up against the inner base of the connector.

Load the primed connector into the crimping tool’s 16–22 AWG die. Before crimping, recheck the position of the wires within the connector. Crimp the connector until the tool springs back open, then repeat the crimp a second time.

Repeat for the remaining set of wires and second spade connector.

Step 7: Reconnect the air heater wires

Attach the connectors from the air heater to those on the harness labeled C003 AIR. The polarity does not matter, so the red and black wires may be connected to either the blue or the brown wires in the harness.

Step 8: Secure the air heater wires

Resecure the air heater wires into the cable clamp.

Install the new air heater assembly - Reconnect & Secure

Reinstalling the inner rear and insulation panels

Overview: After replacing the air heater RTD, reinstall the inner rear panel and insulation.

Step 1: Mount the inner rear panel

Put on a pair of clean nitrile gloves. Orient the inner rear panel with the metal retention tabs facing you. Slide the panel over the air heater inlet. Ensure that the screw holes in the panel align with those in the printer.

Replace the inner rear and insulation panels

Step 2: Secure the inner rear panel

Thread one M4 socket head screw into each of the 13 screw holes in the inner rear panel. Using a 3 mm hex driver, tighten until snug.

Step 3: Prepare the retention tabs

Replace the inner rear and insulation panels
Replace the inner rear and insulation panels

Straighten the three metal retention tabs that secure the rear upper insulation panel to the back of the printer. Ensure that both halves of each tab are parallel to each other. If they are not, they will shred the insulation as the panel is removed.

Step 4: Mount the insulation panel

Slide the upper rear insulation panel in place and fold the tabs over to secure it.

Replace the inner rear and insulation panels

Step 5: Seal the insulation panel in place

Use 100 mm (4 in) foil tape to cover any seams around the rear insulation panel. If the previous tape was peeled off instead of cut, replace the entire piece.

Replace the inner rear and insulation panels

Step 6: Mount and secure the air heater duct

Slide the air heater duct back onto the inlet pipe, then tighten the ring clamp to secure the duct.

Replace the inner rear and insulation panels

Step 7: Secure the nitrogen plenum (Fuse 1+ 30W only)

Using a T20 Torx driver and a 2.5 mm hex driver, reinstall the three T20 screws and two M3 socket head screws that secure the nitrogen plenum to the printer.

Secure the nitrogen plenum

Reinstalling the buffer-side panel

Overview: After installing the replacement air heater, reinstall and secure the buffer-side panel.

Step 1: Align the buffer-side panel with the printer

Lift the buffer-side panel and align its screw holes with those in the printer frame, as shown.

Step 2: Secure the buffer-side panel

Thread one 6 mm M4 countersunk screw into each of the four marked screw holes in the buffer-side panel. Using a 2.5 mm hex driver, tighten until snug.

Remove the buffer-side enclosure panel

Reinstalling the top panel

Overview: After reinstalling the buffer-side panel, reinstall and secure the top panel.

Step 1: Align the top panel

Lift the top panel and place it on top of the printer. Align the screw holes in the top panel with the corresponding holes in the printer frame.

Step 2: Secure the top panel screws

Thread a 6 mm M4 countersunk screw into each of the 18 marked screw holes in the top panel:

Remove the top enclosure panel
Remove the top enclosure panel
Remove the top enclosure panel
  • Four 6 mm screws on the front end of the buffer-side
  • Eight 6 mm screws on top of the printer
  • Six 6 mm screws on the hopper-side

Using a 2.5 mm hex driver, tighten the screws until snug.

Reinstalling the rear panels

Overview: After installing the replacement air heater RTD, reinstall and secure the rear panels.

Step 1: Align the upper rear panel with the printer

Lift the upper rear panel and align it with the four screw holes on the top of the printer.

Step 2: Secure the upper rear panel top screws

Thread the four 6.0 mm screws into each of the screw holes on the top of the printer. Using a 2.5 mm hex driver, tighten the screws until finger tight. You may need to adjust the exhaust duct to correctly position the upper rear panel.

Step 1: Align the upper rear panel with the printer

Step 3: Secure the buffer side panel screws

Thread the two 6 mm screws into the screw holes on the buffer side and the two 6 mm screws into the screw holes on the hopper side. Using a 2.5 mm hex driver, tighten the screws until snug.

Step 3: Secure the buffer side panel screws

Step 4: Secure the hopper side panel screws

Thread the two 6mm screws into the holes on the hopper side. Using a 2.5 mm hex driver, tighten the screws until snug.

Step 4: Secure the hopper side panel screws

Step 5: Secure the upper rear panel grounding screws

The two black upper rear panel screws are circled in red. The two chrome upper rear panel grounding screws are circled in blue.

Thread the panel screws into the indicated screw holes on the upper rear panel. Refer to the image for the correct locations of the black and chrome screws. Using a 2.5 mm hex driver, screw in the two black panel screws and two chrome grounding screws securing the upper rear panel to the printer.

Step 5: Secure the upper rear panel grounding screws

Notice:

The placement of the chrome screws is critical to the printer's electrical grounding. Incorrect placement may lead to printer damage.

Step 6: Slide the exhaust duct into position

Step 6: Slide the exhaust duct into position
Step 6: Slide the exhaust duct into position

Slide the end of the exhaust duct with the ring clamp back onto the exhaust pipe. Ensure the exhaust duct presses against the insulation panel.

Step 7: Tighten the exhaust duct ring clamp

Using a 6.5 mm flathead screwdriver, tighten the ring clamp until finger tight.

Step 8: Secure the exhaust inlet screws

Open the filter cabinet door on the printer. Thread the four 8.0 mm screws into the screw holes. Using a 2.0 mm hex driver, screw in the four exhaust duct screws until finger tight.

Step 9: Check the exhaust duct seal

To ensure there is no gap between the exhaust duct’s mounting plate and the filter cabinet housing, shine a flashlight or other light source around the exhaust inlet inside the filter cabinet. If any light is visible behind the filter cabinet, the duct is not properly sealed. If necessary, use a 2.0 mm hex driver to tighten the exhaust duct screws. Close the filter cabinet door when finished.

Step 8: Secure the exhaust inlet screws

Step 10: Secure the lower rear panel grounding screws

The six black lower rear panel screws are circled in red. The four chrome lower rear panel grounding screws are circled in blue.

Thread the panel screws into the indicated screw holes on the lower rear panel. Refer to the image for the correct locations of the black and chrome screws. Using a 2.5 mm hex driver, screw in the six black panel screws and four chrome panel grounding screws securing the lower rear panel to the printer.

Step 1: Remove the lower rear panel screws

Notice:

The placement of the chrome screws is critical to the printer's electrical grounding. Incorrect placement may lead to printer damage.

Step 11: Reinstall the Wi-Fi antenna (optional)

Screw the Wi-Fi antenna onto the jack on the back of the unit.

Finalizing the repair

Overview: After installing the replacement air heater RTD, power on the printer and perform final checks.

Step 1: Power on the printer

Connect the power cable to the printer and the power supply. The printer initializes.

Step 2: Test the repair

Start a print. Monitor the printer to ensure that the print proceeds normally. Contact Formlabs Support or your certified service provider to share the results of the procedure.