ABS

From RepRapWiki
Jump to: navigation, search


Contents

Introduction

Acrylonitrile Butadiene Styrene (ABS) is a commonly used thermoplastic as it is lightweight and can both be injection molded and extruded. It has better mechanical properties than HDPE and less brittle than PLA but handles higher temperatures better for applications such as extruder's and X-carriages setups without a fan.

  • ABS is good because it is easier to buy and requires less force to extrude than PLA as it has a lower coefficient of friction. This makes its extrusion characteristics better for small parts, compared to PLA. The downside of ABS is that it has to be extruded at a higher temperature: Its glass transition temperature is ~105 °C. ABS is amorphous and therefore has no true melting point, however 230°C is the standard for printing.

Fumes

ABS creates mild, tolerable fumes while being extruded. These fumes, while usually tolerable, may be dangerous for people (or pet birds) with chemical sensitivities or breathing difficulties. Make sure that your printer is in a well-ventilated area and make sure to avoid breathing the fumes. Rutkowski and Levin describe the possible combustion products of ABS in their literature review (Fire and Materials. Vol. 10, pp. 93-105 (1986) [1]).

Heater Settings

200-250 C, depending on your particular plastic.

Sample temperatures with a Makergear 0.5 mm hotend:

Ultimachine Red ABS: 215 C

Ultimachine Natural ABS: 230C

Extrusion width

There has been some evidence that pigment may affect extrusion width. If you are switching plastics a lot, it is a good idea to measure the extrusion before going through the toolpath process.

Pigment can also affect the ideal nozzle temperature.

NB My ABS filament is quite soft, so a hobbed bolt cut with a dremel tool shreds it easily. A bolt cut with 3mm tap seems to work much better (at least with a Wades Extruder) --DGM3333 21 Aug 2012

Build Surface and distortions

ABS is bad because it tends to warp catastrophically off the build platform when printing large parts. This can be remedied by using a heated build platform (in which case it is just as nice as PLA and because it requires less force to extrude, is easier to print with!).

ABS will stick to acrylic at low temperatures and to PET or Kapton tape if the bed is hot. It has also been reported that ABS will stick to glass with a liberal coating of hairspray.

On a cold bed ABS can be printed on masking tape by putting a thin layer of super-glue (cyanoacrylate) on the tape before printing.

Availability

Check out Printing Material Suppliers. Also, check the forums... someone might be able to ship you some for cheap.

ABS filament generally costs around US$20/lb. A cheaper ABS should raise suspicion of being a fake ABS - a mix of ABS and HIPS (cheaper) that will not have ABS properties.

Further reading