Filament Conditioning Accessory

Filawarmer — Strengthens Brittle Filament

An in-line filament heater that warms the filament to 60°C just before it reaches the extruder — resetting spool memory and reviving brittle filaments. Essential for TVF Filamet™, life-saver for any aged or brittle PLA spool.

60°C In-line Heat Resets Spool Memory Revives Brittle Filament Bowden & Direct Drive Works with PLA & Filamet™
The Virtual Foundry Filawarmer in-line filament heater

A small accessory that fixes a big print problem

The Filawarmer is an in-line heating sleeve that the filament passes through on its way from the spool to the extruder. It warms the filament to 60°C, which is enough to reset the curl memory it picked up sitting on the spool and to soften any brittleness from age or storage.

It was designed for TVF Filamet™ metal-loaded filaments — which are heavier and stiffer than PLA, and consequently more prone to snapping at the extruder — but it’s equally effective on aged PLA and any other brittle plastic filament you’ve been about to throw out.

Required for reliable Filamet™ printing. Metal filament is roughly 4× heavier than PLA. The Filawarmer is what makes long Filamet™ prints survive without snapping at the extruder — especially on Bowden setups. Included in the TVF Print & Sinter Kits for this reason.

How it works

Three things happen when the filament passes through the Filawarmer.

1. Reset the curl memory

Filament that’s spent weeks or months on a spool wants to stay curled. Heating to 60°C anneals it back to straight before it hits the extruder. The effect lasts ~24 hours after the warmer is unplugged.

2. Soften brittle plastic

PLA goes brittle with age and humidity. The same gentle heating restores flexibility — you can save spools you were about to throw out.

3. Reduce extruder snap

Pre-heated filament is more flexible at the bend into the extruder, dramatically reducing the chance of mid-print snaps — especially on Bowden setups and with heavy metal filaments.

Who needs a Filawarmer

Buy this if…

  • You print TVF Filamet™ metal filaments — this is essential, not optional
  • You have a Bowden printer that’s eaten more than one filament snap mid-print
  • You have aged PLA spools you’d like to actually use
  • You print exotic filaments (carbon-fibre, glow, metal-fill) that come stiff from the factory
  • You run a print farm and want to reduce the snap rate across mixed-age stock

Skip this if…

  • You only print fresh PLA on a direct-drive printer and never have brittleness issues
  • You’re buying a TVF Print & Sinter Kit — the Filawarmer is already included
  • You want to dry-cycle your filament — this isn’t a filament dryer (and never use a dryer on Filamet™)

Installation — how to position it on your printer

Two patterns depending on your extruder type. Both keep the filament warm at the right point in the path.

Direct drive setup

Position the Filawarmer 230–300 mm above the highest point of the extruder. The filament passes through the warmer just before it enters the extruder gears.

Examples: Prusa MK3S/MK4, Bambu Lab A1 Mini, most direct-drive Crealities.

Bowden setup

Place the Filawarmer directly below the feeder unit. The filament is warmed just before it’s pushed into the Bowden tube — the highest-stress part of a Bowden filament path.

Examples: Bambu Lab X1/P1 (with AMS), Ender 3 V2, FlashForge Bowden machines.

Tip — combine with the AMS for Bambu users. If you’re running a Bambu Lab AMS, route the filament through the Filawarmer between the AMS and the printer’s feeder. This keeps the AMS swapping logic intact while warming the active filament.

Specifications

Specification Details
Operating temperature 60°C
Filament compatibility All TVF Filamet™ metal filaments, PLA, and most brittle plastic filaments
Filament diameter 1.75 mm and 2.85 mm compatible
Direct drive position 230–300 mm above the extruder’s highest point
Bowden position Directly below the feeder
Effect duration after unplugging Approximately 24 hours
Origin Made in South Central Wisconsin, USA

Frequently asked questions

Is this a filament dryer?

No. A filament dryer cycles a whole spool at high temperature for hours to drive out absorbed moisture. The Filawarmer is the opposite — an in-line gentle heater that conditions the filament moments before it enters the extruder. Important: never put TVF Filamet™ in a filament dryer — the heat degrades the binder and ruins the spool.

Do I really need this if I’m only printing PLA?

Not for fresh PLA. But if you have aged PLA spools (months or years old) that snap mid-print, the Filawarmer can revive them and save the cost of replacements. It’s also useful for any exotic filament that arrives stiff or brittle from the factory.

Will it work with my Bambu Lab AMS?

Yes. Route the filament through the Filawarmer between the AMS output and the printer’s feeder. The AMS continues to handle filament selection and swapping, while the Filawarmer conditions whichever filament is currently active before it reaches the extruder.

Why 60°C and not higher?

60°C is hot enough to reset spool memory and soften brittle plastic, but well below the glass-transition temperature of PLA (~60°C onset, full softening higher) and the binder degradation point of Filamet™. Higher temperatures would risk softening the filament so much it deforms in the extruder gears or damages the metal-loaded binder.

How long does the filament stay flexible after passing through?

Approximately 24 hours after passing through the warmer (or after the warmer is unplugged with filament inside). For continuous prints, leave the Filawarmer powered on for the duration of the print to keep the active filament conditioned.

Do I need this if I bought a Print & Sinter Kit?

No — the Copper Print & Sinter Kit and the Getting Started Bundle both include a Filawarmer. Buy the standalone Filawarmer if you already have filament but don’t have a warmer, or if you want a second one for a different printer.

Works perfectly with

The Filawarmer is purpose-built for the TVF Filamet™ range. Pair with any of these:

Copper Filamet™

86–90.7% pure copper after sintering. Lowest sinter temperature in the TVF range.

Bronze Filamet™

86–90% pure 89/11 tin bronze. The easiest TVF material to print and sinter.

Getting Started Bundle

Bronze filament + Filawarmer + crucible + ballast in one purchase. Includes a Filawarmer.

Made in South Central Wisconsin, USA. World-class technical support provided for all TVF products.

(TVF-FILAWARMER)

SKU TVF-FILAWARMER
Brand The Virtual Foundry
Shipping Weight 1.0000kg
Shipping Width 0.150m
Shipping Height 0.100m
Shipping Length 0.200m

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