Debinding and Sintering Filament

Note: Debinding happens with heat in the same furnace or kiln used to sinter your print. No special debinding equipment is needed.

Debinding and Sintering Bronze & Copper and Filamet™

Items Needed:

Kiln / Sintering Furnace
Refractory Container (Crucible)
Sintering Refractory Ballast: AI₂O₃ & Magnesium Silicate with Sintering Carbon

Pack:

BC1: Place AI₂O₃ refractory in the crucible
BC2: Bury the print in the AI₂O₃, centered in the crucible
BC3: Tamp down and pat the sides of the crucible
BC4: Part should be surrounded by refractory
BC5: Keep at least 15mm between the part and the crucible walls and top of refractory
BC6: Put the crucible in the kiln

Debind:

BC7: Ramp furnace at a rate of 55.6°C (100°F) per hour to 482°C (900°F)
BC8: Hold at 482°C (900°F) for 4 hours*
BC9: Let furnace cool to room temperature

Apply Sintering Carbon:

BC10: Turn off the kiln and unplug it to cut the power
BC11: Remove the part and refractory from the crucible
BC12: Place Magnesium Silicate refractory in the now empty crucible
BC13: Bury the part in the Magnesium Silicate, centered in the crucible, leaving at least 25mm empty at the top of the crucible
BC14: Tamp down and pat the sides of the crucible
BC15: Part should be surrounded by refractory
BC16: Keep at least 15mm between the part and the crucible walls and top of refractory
BC17: Fill up the whole 25mm of space on the top with the Sintering Carbon
BC18: If possible, place a cover over the crucible – Don’t seal it (the cover can be tool wrap, ceramic or kiln paper. It is used to preserve Sintering Carbon.)
BC19: Put the crucible back in the kiln

Sinter:

BC20: Ramp furnace at a rate of 111.1°C (200°F) per hour to the Sinter Temp (chart below)
BC21: Hold at the Sinter Temp for 5 hours

Cool Down:

BC22: Program ends – let furnace cool to room temp from Sinter Temp

*Hold times listed are ideal for a part that is less than a 50mm cube. Hold longer for larger or very thick parts and/or larger crucibles.
Experiment with hold times if the parts are not sintered correctly.
Expected shrinkage with these instructions is 7 – 10%.

Debinding and Sintering Inconel® 718, Stainless Steel 17-4, & Stainless Steel 316L Filamet™

Items Needed:

Kiln / Sintering Furnace
Refractory Container (Crucible)
Sintering Refractory Ballast: Steel Blend and Sintering Carbon

Pack:

S1: Place Steel Blend refractory in crucible
S2: Bury the print in the Steel Blend
S3: Tamp down, don’t pack or smoosh
S4: Leave about 40mm of room on top
S5: Part should be surrounded by refractory
S6: Keep at least 15mm between the part and the crucible walls and top of refractory
S7: Put the crucible in the kiln

Debind:

S8: Ramp furnace to 204°C (400°F) over the course of 2 hours.
S9: Hold at 204°C (400°F) for 2 hours*
S10: Over the course of 2 hours, ramp to 427°C (800°F)
S11: Hold at 427°C (800°F) for 2 hours*
S12: Let furnace cool to room temperature

Sinter:

S13: Fill the space at the top of the crucible with Sintering Carbon
S14: Ramp furnace to 593°C (1100°F) as fast as it will go
S15: Hold at 593°C (1100°F) for 2 hours*
S16: Over the course of 2 hours, ramp to Sinter Temp (chart below)
S17: Hold at Sinter Temp for 4 hours*

Cool Down:

S18: Over the course of 6 hours, ramp down to 593°C (1100°F) – do not hold
S19: Program ends. Let furnace cool to room temp from 593°C (1100°F)

name	Alumina Crucible	Graphite Crucible	Stainless Steel Crucible	Refractory	Debind Temperature	Ramp Time	Sinter Temperature
Bronze	Recommended	Good	Good	AI₂O₃ & Magnesium Silicate Sintering Carbon	482°C (900°F)	7.635 Hours (Step BC20)	885°C (1625°F) (Step BC20)
Copper	Recommended	Good	Good	AI₂O₃ & Magnesium Silicate Sintering Carbon	482°C (900°F)	9.46 Hours (Step BC20)	1052°C (1925°F) (Step BC20)
Stainless Steel 17-4	Recommended	Good	X	Steel Blend Sintering Carbon	427°C (800°F)	_	1287°C (2350°F) (Step S15)
Stainless Steel 316L	Recommended	Good	X	Steel Blend Sintering Carbon	427°C (800°F)	_	1287°C (2350°F) (Step S15)
Inconel 718	Recommended	Good	X	Steel Blend Sintering Carbon	427°C (800°F)	_	1287°C (2350°F) (Step S15)

Stainless Steel Crucibles will be used up after a few cycles.
Al2O3 and Steel Blend can be reused for multiple sinter cycles.
Note: Furnaces can vary in temperature by 38°C (100°F) from the furnace readout which can adversely affect results. Test furnace temperature with an independent thermometer.
No sintering support is available for Aluminum 6061, Rapid 3DShield Tungsten, Silicon Carbide and Titanium 64-5 Filamet™ materials.
Aluminum’s Oxides pose a challenge in the sintering process and it needs more than just an oxygen-free environment. Aluminum and its alloys can only be effectively sintered in pure nitrogen or in a vacuum. Argon has been used in the past, but can create some bonding issues between particles. There are conditions that aluminum requires depending on the alloy and geometry. Simple aluminum alloys such as 2014 can be sintered in dry nitrogen, but the furnace needs to be tight (-50 dewpoint) and uniform (±1°F) temperature control. Sintering development for Aluminum 6061 is underway. Current information and updates can be found here, as well as in our Discord server here.
Oxygen is damaging to the metal sintering process. Sintering Carbon is used to combat this. Titanium is extra troublesome because it absorbs oxygen like crazy. It will pull oxygen out of a standard kiln’s insulation. Compounding the issue is titanium’s reactivity in the presence of oxygen and heat. The solution that we understand today is to use an all-metal kiln and a chamber thoroughly flooded with ultra high-purity argon.

Debinding and Sintering H13 Tool Steel

Items Needed:

Kiln / Sintering Furnace
Refractory Container (Crucible)
Sintering Refractory Ballast: Steel Blend and Sintering Carbon

Pack:

S1: Place Steel Blend refractory in crucible
S2: Bury the print in the Steel Blend
S3: Tamp down, don’t pack or smoosh
S4: Leave about 40mm of room on top
S5: Part should be surrounded by refractory
S6: Keep at least 15mm between the part and the crucible walls and top of refractory
S7: Put the crucible in the kiln

Debind:

S8: Ramp furnace at 33°C (60°F)/hour to 204°C (400°F)
S9: Hold at 204°C (400°F) for 2 hours*
S10: Ramp furnace at 17°C (30°F)/hour to 427°C (800°F)
S11: Hold at 427°C (800°F) for 6 hours*
S12: Ramp furnace at 33°C (60°F)/hour to 538°C (1000°F)
S13: Hold at 427°C (800°F) for 2 hours*
14: Let furnace cool to room temperature

Sinter:

S15: Fill the space at the top of the crucible with Sintering Carbon
S16: Ramp furnace at 333°C (600°F)/hour to 1260°C (2300°F)
S17: Hold at 1260°C (2300°F) for 4 hours*

Cool Down:

S18: Ramp furnace at 111°C (200°F)/hour to 593°C (1100°F) – Do not hold
S19: Program ends. Let furnace cool to room temp from 593°C (1100°F)

TVF Webinar: Debinding and Sintering Filamet

Frequently Asked Sintering QuestionsText

How Much Will My Part Shrink During Debinding and Sintering?

Debinding and Sintering Amaco 46-D, White 25-D, and X-23 Ceramic Clay Filamet™

Items Needed:

Kiln / Sintering Furnace
Refractory Container (Crucible)
Sintering Refractory Ballast: AI₂O₃ or sand (The purpose of the refractory is to hold the part’s shape and any material that won’t burn up or deform in the temperatures listed below can be used.)

Pack:

CC1: Place AI₂O₃ refractory in the crucible
CC2: Bury the print in the AI₂O₃
CC3: Tamp down, don’t pack or smoosh
CC4: Part should be surrounded by refractory
CC5: Keep at least 15mm between the part and the crucible walls and top of refractory
CC6: Put the crucible in the kiln

Debind:

CC7: Ramp furnace to 204°C (400°F)
CC8: Hold at 204°C (400°F) for 2 hours*
CC9: Over the course of 2 hours, ramp to 427°C (800°F)
CC10: Hold at 427°C (800°F) for 3 hours*

Sinter:

CC11: Over the course of 4 hours, ramp to the 649°C (1200°F) – do not hold
CC12: Over the course of 5 hours, ramp to 1232°C (2250°F)
CC13: Hold at 1232°C (2250°F) for 4 hours*

Cool Down:

CC14: Program ends – let furnace cool to room temp

*Hold times listed are ideal for a part that is less than a 25mm cube. Hold longer for larger or very thick parts and/or larger crucibles
Experiment with hold times if the parts are not sintered correctly.

Debinding and Sintering Pyrex® (Borosilicate) Glass Filamet™

IItems Needed:

Kiln / Sintering Furnace
Refractory Container (Crucible)
Sintering Refractory Ballast: Magnesium Silicate

Pack:

PB1: Place Magnesium Silicate refractory in the crucible
PB2: Bury the print in the Magnesium Silicate
PB3: Tamp down, don’t pack or smoosh
PB4: Part should be surrounded by refractory
PB5: Keep at least 15mm between the part and the crucible walls and top of refractory
PB6: Put the crucible in the kiln

Debind:

PB7: Ramp furnace to 204°C (400°F)
PB8: Hold at 204°C (400°F) for 2 hours*
PB9: Over the course of 2 hours, ramp to 427°C (800°F)
PB10: Hold at 427°C (800°F) for 3 hours*

Sinter:

PB11: Over the course of 5 hours, ramp to 843°C (1550°F)
PB12: Hold at 843°C (1550°F) for 3 hours

Cool Down:

PB13: Program ends – let furnace cool to room temp from Sinter Temp

Temperatures may vary based on kiln brand and size.
Note: Furnaces can vary in temperature by 38°C (100°F) from the furnace readout which can adversely affect results. Test furnace temperature with an independent thermometer.
No sintering support is available for Silicon Carbide and Zirconium Silicate (Zircopax®) Ceramic Filamet™ material. To partner on the development of this process, contact us.