HTPLA – Midnight Multicolor

Specs

Semi crystalline, heat treatable PLA for high temp use

Density: 1.24 g/cc
Length: 346 m/kg (1.75) 130 m/kg (2.85)
Typical Printing Temp: 205-225 C
Glass Transition (Tg)*: 60 C
Peak Crystallization (Tc)**: 95-115 C
Onset to Melt (Tm)***: 155 C
Typical change when heat treated: -2% x/y +1% z

Link to Safety Data Page

*max use with no heat treat & max platform temp
**heat treating @ temp 10+ min depending on size/mass
***max use when heat treated (annealed or crystallized)

Print

HTPLA prints well at 205-225 C, however it’s important to match temp to your hardware & volume flow rate. With a typical hotend, you should be able to print at 205 C without jamming at a low flow rate. In machines with hardware that tends towards jamming, consider this video with Joel Telling.

Lower volume flows require lower temps, while higher volume flows require higher temps. In the previously-mentioned video, one way to overcome jamming is to set your temp to a higher-than-typical 240 C. This should then be matched with a high flow rate for a quality printing result.

For direct drives with a short distance between drive gears & nozzle, volume flows can approach 7-8 cubic mm/s or more if printing hot to overcome jamming. For bowden tubes where the distance between drive gear & nozzle are great or less powerful hotends, as little as 2 and as much as 4 cubic mm/s may be the limit. Beware of unintended speed changes from faster infills & slowing down for outlines or short layers. Consider our Ultimaker-specific blog for more on this topic.

A constant speed throughout the part is ideal from an extrusion perspective. Knowing your extrusion width, layer thickness & speed you can calculate your volume flow rate with the calculator like found in the previously-mentioned Ultimaker blog. Alternatively, if you know your volume flow rate limit, extrusion width & layer thickness, you can calculate your speed limit.

Heat Treat

PLA & HTPLA are amorphous in structure as printed (no heat treating) & though both are adequate performers in an office environment, they have poor temperature stability, loosing significant stiffness at temps nearing 60 C. Different than standard PLA, HTPLA is designed to survive heat treating for higher temp stability in a no/minimal load condition to near onset of melting (155 C). That’s an astonishing improvement in thermal stability compared to standard PLA after a quick bake in the oven after printing.

In as little as 5-10 minutes for small, thin parts, HTPLA quickly crystallizes in an oven at 95-115 C (200-240 F) to become more stiff & hold form above glass transition (60 C). Depending on part geometry, setup & technique, parts can deform and shrink. Best results are with flat and/or supported parts with 100% infill. In this instance we experienced x/y shrinkage of about 2% & growth of about 1% in z.

Be sure to avoid hot spots (non-radiating surfaces & no glowing coils) in the oven used for baking & experiment before baking a prized part. Un-printed filament works great for experimentation & translucent makes the transformation most visible! Heat treating is an art, but the resulting improved thermal performance, if needed, is well-worth exploring. You’ll be shocked by the improved thermal stability of your HTPLA parts!!!

High Temperature PLA ( HTPLA )

Looking for increased heat resistance without the need to switch to ABS? Protopasta High Temperature PLA offers heat deflection of up to 88° C (190.4° F) compared to standard PLA of 45-54° C (113-135° F). This makes it a great choice for moving parts (gears, RepRap pieces, etc) or prints that would face moderately high temperatures.