Hey there everyone!
I recently (past 6 months) got a printer and have really enjoyed fixing problems around the house and repairing tools and items. As a mechanical engineer and DIY home owner, it has opened up an entirely new way to solve problems.
Background
Waste Woes
But, on the flip side, It has made me so much more conscious of plastic waste. While printing parts in a single colour and making double, triple sure my measurements are right helps to reduce the waste, every failed design and poop nugget makes me ever more conscious.
Doing research, I found that while PLA is technically biodegradable and “compostable”, it requires industrial composting, which is not common, at least not where I live. So I have been stock piling my PLA scraps in hopes that eventually come up with a project for them or a safe place to dispose of them.
My research eventually led to finding PHA, an alternative to PLA that is truely compostable. You can chuck it in your backyard composter! It fully breaks down and has no harmful by-products (1).
Finding PHA Filament
I looked around to find some filament to try out and there were a handful of brands that popped up. I settled on getting some allPHA from ColorFabb. Once ordered, I was flabbergasted at how expensive it was! With 2x 750g rolls costing me $107 canadian credits (~$77 USD) + $58 CAD (~$42 USD) imports! This was in April when new US tarriffs and such had not quite landed, so YMMV. But I went with it anyway, figured It would be a good experiment and provide me $160 CAD worth of harmless entertainment.
One major thing to note here is that not all PHA filament is created equal. Some suppliers, advertise PHA filament that is mixed PLA and PHA (probaby >50.1% PHA) to make it easier and cheaper to make. This obviously still has PLA in it and therefore will NOT compost in your backyard without leaving microplastics. Also worth noting is that ColorFabb’s PHA uses natural and inert compounds to dye there allPHA filament. White requires more dye, so the colouring effects the print properties. Black will print closer to the natural, and white will print notably different (2).
ColorFabb does not make much of this stuff, as it is still difficult to get raw supply and difficult to manufacture into filament. They continue to do runs of it and it seems to sell out on there website pretty quickly, so keep and eye out for a restock and grab some when you can!
TLDR: I don’t like plastic waste and ordered some (expensive) PHA to try out. If you order some, check that the filament is 100% PHA and not a PLA/PHA mix.
PHA’s Important Properties
As I am pretty new to PHA filament, most of this info is based on my research and info provided by PHA filament suppliers and other users. More discussion can be found on r/3DPrinting_PHA page on Reddit.
Basic Properties:
| Properties | Manufacturer | Community |
|---|---|---|
| Print Temp: | 190-200 °C | 190-240 °C |
| Fan Speed: | 100% | 100% |
| Fan off for first # layers | 3 | 1 |
| Bed Temp: | 0°C (Bed Heat Off) | 0°C (Bed Heat Off) |
| Recommended Print Bed: | Smooth PEI | Smooth PEI |
| Recommended Bed Prep: | 3DLac Glue | Glue |
| Recommended Print Mods: | Brim | Brim + Extra Fans |
Special Considerations
PHA behaves differently than other filaments. PLA does not change much with temp and therefore does not have many issues with warping. ABS/ASA expands at high temps and contracts when cooled, so warping is a serious issue requiring a heated chamber to keep it from contracting too much while printing. PHA also warps, but for a different reason. With the glass transition temp of PHA being 5°C, the polymer crystallizes and shrinks. At higher temps, like printing temps, this happens much faster. So, the solution is to cool the plastic down very quickly after extruded. One manufacturer even uses a water-bath to cool the filament down quickly when manufacturing it! Many PHA users have recommended having desk/standing fan pointed at the print bed while printing to help get even more airflow to cool the part. Another recommendation was to raise the print speed to the upper limit of the PHA filament so that the nozzle spends less time over the extrusion, reducing the heat it dumps and allowing the airflow to cool it faster.
Purpose
This is meant to be a shared journey of learning to print with PHA. Recommendations and criticisms are welcomed! Please refrain from adding non-constructive comments that just add noise to the information. I hope this can serve as a place for other’s to come and learn how to work with PHA filament.
[Disclaimer: Reference links like (#) are not necessarily reliable sources. Do your own research if this really matters. I’m just a stranger on the internet trying to learn from other strangers on the internet]
