Verbatims portfolio of 3D printing materials is far from being extensive so far. In addition the the two classics – PLA and ABS – we find only one material there – the flexible Verbatim Primalloy filament, which premiered last December. We decided to check if printing with it is just as back-breaking as with other soft filaments.
Verbatim Primalloy is a PE-based termoplastic elastomer (TPE). It is available in one colour only: white (a bit dissappointing, to be honest). The filament comes in a Verbatim trademark colourful cardboard box and is protected by a vacuum-sealed bag with desiccant. 500 grams of the material costs …. euros, (that is … euros more than NinjaFlex, which is available in a broad range of colours). The recommended printing temperature is 215-240ºC.
The good people at Verbatim give us some advice with respect to printing using Primalloy filament:
- For best performance, use Polymide Tape (Kapton™ Tape) with a heated build platform (40º – 50º C)
- To prevent layer drooping, apply forced air cooling on object as it builds.
- To prevent feed jams, utilize slow print speeds (≤ 30 mm/s) and turn off retraction. Avoid excessive pressure in the pinch feeder.
- Not recommended for printers with significant distance between the pinch feeder and hot end (eg. >15mm).
That being said, for our first print, a bicycle handlebar grip, we forgot to turn off retraction. The wretched result can be seen below:
The grip was printed with hotend at 230ºC and bed at 65ºC (with glue stick to fix the model to the platform). We used the Monkeyfab PRIME 3D printer.
Here is an observation: when Primalloy is heated to the printing temperature, it becomes transparent. It looses the transparency and becomes milky white upon cooling down, which is clearly visible especially on the first layer, when the deposited material appears somewhat delayed with respect to the movement of the printing head.
Our next shot is a short piece of a ribbed hose. This time we turn off the retraction. We also used the spray-on glue, Dimafix, instead of the glue stick. This turned to be insufficient, as the print came off the platform shortly.
Back to the glue stick, then. Up to this point had been quite sceptical about Primalloy. With this attempt, our way of looking at the filament changed completely. The print was flawless:
The printed object is very robust, it can be squeezed and bended and nothing breaks. Such a hose could be easily used in a working prototype.
Our third attempt is, more or less, a huge hemispehere. It prints well, until… it does not. Towards the very end, out of the blue, the filament tangles up right after the extruder – a characteristic downside of flexible filaments.
In our last effort we wanted to test Primalloy on a model that, contrary to the previous ones, requires some retraction – a teddy bear. Nevertheless, we leave the reatraction disabled, knowing that enabling it would wreck the printing process. No surprise, the printout has lot of strings. Its easier to deal with stringing, though, than with holes in the model. We can remove the string, although it has to be noted that it is not that easy as, for instance, in case of Woodfill filament, where it is sufficient just to lightly touch the surface with a file. With Primalloy, we need really sharp and precise cutting pliers and lots of time.
It is worth mentioning that Primalloy does not warp on overhanging corners, as can be seen in the picture below (teddy bear’s arms). Apart from the stringing, the surface of the model is uniform and very nice, and the geometry of the bear is very accurate.
All in all, we were positively surprised that only one out of four prints was ruined due to tangled filament (other flexibe filaments we got our hand on were much worse in terms of this). One has to note that the overall quality of the obtained prints was very good and the models were very robust. Taking all this into account, we are leaning towards the opinion that Primalloy might be the best flexible filament we have ever used. And since we have heads full of ideas on how to use the material, be prepared to read about it again soon.