Working with Filamet™ and Reel Placement

Due to its high metal content, Filamet™ will inherently break more easily than standard PLA. Following these instructions will make Filamet™ easy to use.

  • Place the spool so that pull and friction are reduced as much as possible.

    • Reel Placement - Direct Drive: Try hanging the reel just above the printer. Any way to reduce friction and pull will greatly reduce chances of breakage during printing.

    • Reel Placement - Bowden: The spool should be placed in a way that the filament comes off straight into the feeder.

  • Use a FilaWarmer to ease the path from spool to printer.

    • The metal particles in Filamet™ are surrounded by plastic. This plastic keeps the memory of its shape on the spool. As Filamet™ passes through the warmer, the memory of the Filamet™ is reset and prints with ease. This effect lasts about 24 hours.

    • Caution! Heating the entire spool at once will cause the filament to become extremely brittle. It’s important to heat only the single strand as it goes into the printer.

  • To report any issues with Filamet™ after trying a FilaWarmer, please contact

FilaWarmer Setup

Stainless Steel: The FilaWarmer comes pre-programmed to 60°C - perfect for Stainless Steel 316L Filamet™.
Bronze and Copper: Adjust the temperature to 45°C.

For best results, station the Filamet™ spool above the printer to minimize any bend of the filament as it comes off the spool.

Hang the FilaWarmer so that the top of the warming tube is at the same level as the spool center hole. Purchase a FilaWarmer in our Online Store.

Recommended Nozzle

Copper, Bronze, Stainless Steel 316L, Aluminum 6061 and Titanium 64-5 Filamet™, use a 0.6mm or larger standard stainless steel nozzle.

High Carbon Iron Filamet™, use a 0.8mm or larger hardened nozzle.

Printer Heat Settings

205-215°C (401-419°F)

Set print bed to 50°C (122°F) (optional)

Print Bed Preparation

Glass Print Bed: Apply a layer of glue using a glue stick. To remove the print, use a spray bottle with water and a razor blade.

Non-Glass Print Bed: Apply a layer of blue painters tape. For easier removal of prints, heat the print bed before removing the print.

Note: Do not print Filamet™ on PEI. Prints will weld to the print bed.

Print Speed

30mm/sec (1800mm/min) to start.

Layer Height

Many slicers lay down an extra wide first layer to get good adhesion to the bed.

This is not a problem unless the first layer is very thin. With traditional PLA, it will simply squeeze out at the sides. Filamet™ is more viscous which slows this process. If the printer nozzle seems clogged, it may be that the nozzle is too close to the bed on the first layer. Once dialed in, some users are printing down to a layer height of 0.1mm.

Printing Tips

  • Filamet™ prints just like any other PLA 3D printing filament, with one exception... start slow. Rushed prints are the most common cause of rough prints.

  • Because Filamet™ is more than three times heavier than plastic filament, three times more energy is needed for print heads to heat the material, often taking more time.

  • Some users have added larger heaters to their print heads in order to get higher print rates.

  • With experience, prints can be faster, but for a quick win on a first try, start at about 30mm/sec (1800mm/min). Increase to normal speed as experience is gained.

TVF’s Simplify3D FFF profiles: Use as a base for starting to use Filamet™.


Sanding and polishing our metal filaments
With heat, our metal filament becomes clay-like. It can be carved, re-sculpted, pieces can be added and seams smoothed.

How to avoid melting when sanding metal filament
Important! Constant movement is necessary when sanding to avoid unintentional melting. Experimenting is worthwhile.

Needle file:  To make print lines vanish, sand the surface even. The loose particles from sanding are smashed into the print line gaps with the heat from the friction, fixing them in place. This step is complete once the entire print’s surface is smooth and even.

Sandpaper or 3M Radial Disc:  Start with 120 grit sandpaper or 80 grit 3M Radial Disc, and go over every part of the print. The matte surface will become shiny as finer grits are used. Complete the entire surface of the print before moving to the next grit. The Virtual Foundry recommends using 4 grits with 3M and 6 or 7 grits with sandpaper. A nice shine can be achieved with less, but the mirror shine comes closer to the 7, ending around 3000 grit. After sanding, rub the print down with some flannel or a sunshine cloth to clean off loose particles. A mirror shine should be evident at this phase, even before the last step.

Sewn Buff and Zam:  Place sewn buff on a rotary tool, then liberally apply zam to the buff and to your print. The print will melt if it gets too hot, so it is critical to keep the buff moving and continue to apply zam liberally. It may be useful to practice this step on a simple print or a “failed print.”


Sintering in an Open Environment
(Copper and Bronze Filamet™ Only)

Items Needed:  
Refractory Container (Crucible)
Magic Black Powder (available in our Online Store)
Small paint brush

Mix the Magic Black Powder:  Start with a mixture of 1.8 parts MBP to 1 part water and adjust as needed. The mixture should be a bit on the runny side but have a thicker consistency than water. Starting with a thinner mixture allows more time to paint on the first layer before the MBP sets up too much.

Prep the Print:  Manually paint a layer of the MBP mixture onto the print, carefully covering all surfaces. This coat grabs all the detail of the print and makes a mold that holds the print’s shape while firing. During the painting process, the MBP is thickening in the Crucible (metal cylinders work best as Crucibles). Put the print into the MBP while it's just barely thick enough to suspend it. If it’s too thick, air pockets and bubbles can occur and create deformities in the fired print

Tip:  Magic Black Powder application video

Fire:  Place the Crucible in the furnace and begin the firing cycle.

1. Start at room temperature.

2. Ramp temp at full speed to 150°C (302°F) and hold for 1 hour, 15 minutes.

3. Over the course of 200 minutes, ramp temp to 400°C (752°F). Do not hold.

4. Over the course of 180 minutes, ramp temp to 983°C (1801.4°F) for Copper or 865.6°C (1590°F) for Bronze and hold for 240 minutes.

Tip: Once the container passes 315°C (599°F), minimize its exposure to oxygen (i.e., do not open the furnace, make sure peepholes are plugged, etc.).

Quench:  This step ends firing and cools the print. While the print sinters, prepare a 1-2 gallon metal container of water. When the sintering time is up, use tongs and heat resistant gloves to remove the print container from the furnace and slowly and gradually place directly into the water. The water will hiss and bubble as the project cools, and MBP will disintegrate. Retrieve the object from the water when cool, after about 3-5 minutes.

The Magic Black Powder closest to the print should be dark gray. If it is white, troubleshooting is needed to eliminate oxygen. Try sealing the container with stainless steel tool wrap.

Initially, the print will be dark: this is a very thin surface layer. Much of it can be removed by pickling, but sandblasting, fine steel wool or tumbling will also get the job done. The Virtual Foundry recommends 3M Radial Bristle Discs.

*Note: Every situation is different and you may need to modify your sintering times and temperatures based on your application and use of our materials. These are general guidelines to get you started.*

For first trials, plan for 7% shrinkage of the part overall through the sintering process.

Tip: The mechanical properties of the final product are directly related to how long the print is held at the sintering temperature. If the end product is powdery and brittle, it’s under-sintered. If the print looks like old wrinkled fruit, it’s over-sintered. Eliminate exposure to oxygen to avoid failure due to oxidation.

Print is ready for finish work!

Sintering in a Vacuum
or Inert Environment
(All Materials)

Items Needed:  
Crucible: Firing Container
Powdered Graphite
Mixed Al203 for Copper and Bronze
White Al2O3 for Stainless Steel 316L and High Carbon Iron
(use a mix of graphite and Al2O3 or use Al2O3 alone)
(available in our Online Store)

Prep:  Place the object in the refractory, ensuring the entire print and all surfaces are completely covered and any protruding areas are fully supported. The print must be fully surrounded by the refractory. Ensure that at least 10mm of refractory insulates the print from the walls of the crucible.

Fire:  Place the Crucible in the furnace and begin the firing cycle.

Firing Cycle:

1. Start at room temperature.

2. Over the course of 200 minutes, ramp temp to 205°C (401°F). Do not hold.

3. Over the course of 180 minutes, ramp temp to 400°C (752°F). Do not hold.

4. For Copper: Over the course of 180 minutes, ramp temp to 983°C (1801.4°F) and hold for 440 minutes.

For Bronze: Over the course of 180 minutes, ramp temp to 865°C (1589°F) and hold for 440 minutes.

For Stainless Steel 316L: Over the course of 180 minutes, ramp temp to 1225°C (2237°F) and hold for 240 minutes.

5. End cycle and let furnace cool to ambient temp until Crucible can be removed by hand.


 *Note: Every situation is different and you may need to modify your sintering times and temperatures based on your application and use of our materials. These are just general guidelines.*

* Sintering instructions for High Carbon Iron Filamet™ are being finalized. This page will be updated when those instructions are ready.*

This process takes around 12 hours and has been tested on prints up to 200g.

For first trials, plan for 7% shrinkage of the part overall through the sintering process.

Tip:  The mechanical properties of the final product are directly related to how long the print is held at the sintering temperature. If the end product is powdery and brittle, it’s under sintered. If the print looks like old wrinkled fruit, it’s over-sintered.

Print is ready for finish work!

Filament  Sinter Temp
Bronze Filamet™  865.6°C (1590°F)
Copper Filamet™  983°C (1801.4°F)
Stainless Steel 316L Filamet™  1200°C (2192°F)
High Carbon Iron Filamet™  1250-1350°C (2282-2462°F)
Aluminum 6061 Filamet™  555°C (1031°F)
R3DS Tungsten  1200-1400°C (2192-2552°F)


Furnaces used to sinter objects printed with Filamet™ should meet the requirements below:

Filamet™  Max Temp  Atmosphere  MBP Needed?  Programmable?
Copper & Bronze  2012°F (1100°C)  Open  Yes  Yes
Copper & Bronze  2012°F (1100°C)  Vacuum or Inert  No  Yes
SS316L  2552°F (1400°C)  Vacuum or Inert  No  Yes

Note:  Furnaces can vary in temperature by 100°F (37.8°C) from the furnace readout which can adversely affect results. Test furnace temperature with an independent thermometer.

When a vacuum or inert environment furnace is used, no Magic Black Powder is needed. Instead, use a suitable refractory to support the print's shape. TVF recommends powdered graphite (available in our Online Store).

See the Sintering Furnace Information page for a purchasing resource.


How should I place Filamet™ when I am printing with it?
Ease the pull on the Filamet™ to reduce breakage while printing. Hanging the Filamet™ above the printer works well. A little suspension frame with some free spinning ball bearing action works too.

How strong is Filamet™?
While Filamet™ isn’t as strong as standard PLA (because of the very high metal content), it is still sturdy. Reducing friction on the Filamet™ as it's pulled into the printer is key.

What kind of printer does Filamet™ work on?
Filamet™ works in any Fused Filament Fabrication (FFF) printer. If the printer prints with standard PLA, it will print with Filamet™. If your printer requires that you only use materials from the printer manufacturer, you may not be able to print with Filamet™..

What is the Metal Content of Filamet™?
Copper Filamet™ is 90% metal by mass, Bronze Filamet™ is 87-90% and Stainless Steel 316L Filamet™ is 81-85%.

Is Filamet™ Conductive?
While in its printable spool form, Filamet™ has a PLA binder (20% or less). Through sintering, the PLA binder is burned off and the remaining object has the same conductive properties of whatever metal it is.

What are the print settings for Filamet™?
Printer settings and sinter firing schedule can both be found on the Use Instructions page and printed instructions are included with every order.

I want to sinter a print. Where should I start?
The best way to learn the sinter process is to print the swirly cone model and then follow the sintering instructions on the Use Instructions page which are set for this size model. Sintering times vary by the size of the print.

Where can I find Safety Data Sheets (SDS) for Filamet™?
All SDS are on this page.

Are you going to have more printable metals?
The Virtual Foundry is consistently working on expanding available products. Keep watching this website, our Facebook page and our LinkedIn page for new material announcements. Looking for custom development? Let us know!

What makes Filamet™ special?
Filamet™ makes metal printing available to anyone with a desktop 3D printer - no need to purchase a costly printer to print with metal.

What kind of kiln do I need?
Mainly, the kiln needs to be programmable. The Virtual Foundry offers the same furnace for sale that we use in-house. Check it out here.

What is the mix ratio for Magic Black Powder (MBP)?
As a starting point, consider a ratio of 1 to 2 with 1 cup of water to 2 cups of MBP. This may be a bit on the dry side in which case a bit more water should be added. The goal of the mixture is a bit runny but not like water. A layer of MBP will be painted on to the print to create a mold that holds the object's shape while firing. Be sure to apply to all the detail of the print - cracks, crevasses, etc. While this layer is being applied, the remainder of the MBP mixture will begin setting. Starting with a thinner mixture will offer more time for this process. It's important to have that first layer fully applied and the object into the remaining MBP mixture when the mixture is just barely thick enough to suspend the object. If the mixture is too thick, air pockets may form and create deformities in your fired object.
Note: Metal cylinders work best as the firing vessel.

How should I store Filamet™?
Filamet™ does not appreciate being exposed to air for weeks. When not in use, store Filamet™ in a sealed plastic bag with the desiccant pack included with the product.

I need help! What do I do?
Send us an email. We’d love to help!

Where is the link for the swirly cone model?
Here and at the bottom of every page of this website.

The applications for Filamet™ are endless, everything from jewelry to blocking radiation.

Please share your experience and applications on Facebook.