An Introduction to HIPS Filament
HIPS plastic and its common uses in 3D printing
An introduction into HIPS as a material in the world and in 3D Printing.
Learn what essential equipment you need to print HIPS.
The best 3D printers for printing in HIPS listed.
Best practices and key takeaways when printing in HIPS.
What is HIPS?
High-impact polystyrene is a lightweight, impact resistant variant of Polystyrene (PS) that lends itself to vacuum forming and pressure forming without sacrificing strength.
High-impact polystyrene is a lightweight, impact resistant thermoplastic that lends itself to vacuum forming and pressure forming without sacrificing strength. HIPS can also be recycled by most Australian recycling facilities and is catagorised under the recycling code 6 - Polystyrene.
The majority of us come into contact with HIPS on a daily basis and common uses of HIPS include:
Takeaway Coffee Cup Lids
Form Fitting Packaging
Yoghurt Tubs
Boat Hulls
Toys
Automotive Instrument Panels
Computer and TV Housings
What is HIPS Filament?
HIPS has been widely available as a 3D printer filament for a number of years and continues to be a popular choice for its:
Low Cost
Solubility in D-limoline for use as a soluble support material
Useful material properties
Ability to be easily post-processed
HIPS is currently available as a 3D printer filament in 1.75mm and 2.85mm diameter in a limited range of colours.
What is HIPS filament good for?
Recyclable Parts
Takeaway Coffee Cup Lids, Form Fitting Packaging and Yoghurt Tubs are all examples of things made of HIPS that can be recycled via curbside recycling programs in Australia and New Zealand. For more information on how to successfully recycle your 3D prints, refer to our guide here or contact your local council.
Lightweight Functional Parts
HIPS shares many of the same material characteristics as ABS, including impact resistance and durability albeit to a lesser degree. However, it has the added benefit of being lightweight. Because of this, it is ideal for printing functional parts, such as in models of airplanes and automobiles, that must be lightweight, yet durable and impact resistant.
Investment Casts
A unique property of HIPS is its ability to dissolve in a solvent known as d-Limonene. In this way, HIPS has a similar property to other soluble materials like PVA, which can be used for printing accurate and replicable moulds for investment casting. Concrete moulds are an example.
Soluble Support Material
HIPS’s ability to dissolve in d-Limonene makes it suitable when printed as a support material. A dual extrusion capable printer can achieve this, allowing for the printing of intricate parts where manually removing the support material from hard-to-reach places is impossible. The soluble nature of HIPS also allows for the production of parts that are free of blemishes that may result from removing support material.
Impact Resistant Parts
HIPS is a popular choice for the 3D printing of functional parts due to its great impact resistance and moderate heat resistance (softening at around 92°C). This makes HIPS ideal for 3D printing functional parts that need to withstand repetitive impact loading.
Processability
HIPS can also be easily post-processed. You can sand it, drill it, and even chemically bond it together with Methyl Ethyl Ketone (MEK). An easy way to do this is to paint a thin layer of MEK on two HIPS surfaces and press them together. Compared to standard adhesives, the resulting bond produces a stronger bond between the two parts. This allows large assemblies, made up of many smaller HIPS parts, to be fused together.
Smooth & Polished Parts
D-limoline's solubility in HIPS allows it to be chemically smoothed. Because d-limoline viscous, oily nature, it will not produce vapours in the same way as acetone and as such needs to be applied with a brush or by or by submerging it in a d-limoline bath for 10-20 seconds. The d-limoline will dissolve the surface layer of fillament and results in a shiny, gloss surface finish. In this way, polished parts can be produced with almost imperceptible layer lines.
Looking to find out if HIPS is the right material for your project? Check out our material comparison guide to compare all our 3D printing materials to match the perfect material to your application.
Is HIPS filament safe to print with?
HIPS is used in everyday applications like for takaway coffee cups and in yoghurt tubs and poses no threat in its solid state. Upon melting however, HIPS is known to emit ultrafine particles (UFP's) and volatile organic compounds (VOC's) much like ABS.
These include methylene chloride and styrene, which are known carcinogens. Unfortunately, during the 3D printing process, HIPS is heated to these same temperatures. In order to avoid exposure to hazardous emissions when printing in HIPS, it is essential to take appropriate safety precautions.
To learn how to 3D print HIPS filament safely, check out our guide here!
Is HIPS hard to print with?
HIPS is slightly more challenging to print than comparable materials like PLA. HIPS scores a 3/5 on our Ease of Printing Matrix - a medium difficulty material compared to PLA's easy 5/5.
HIPS |
PLA |
|
|---|---|---|
|
Requires Drying Before Printing |
||
|
Requires Enclosure |
X | |
|
Requires Active Air Filtration |
X | |
|
Requires Special Extruder |
||
|
Requires High Temperatures |
||
|
Ease of Printing Score |
3/5 | 5/5 |
We rated HIPS a 3 filament due to its tendency to warp and the additional hardware required to safely manage the emissions generated while printing.
What do you need for HIPS printing?
It’s vital to ensure that your printer meets the right hardware requirements in order to put yourself in the best position to print in HIPS. It is still possible to print HIPS in the absence of the following equipment. However, it will be a frustrating and constant battle against warping, parts that dislodge during the printing process, and layer delamination.
Active Air Filtration or Ventilation
A heated bed
Standard Extruder
Enclosure (with HEPA filter)
Appropriate Build Surface (PEI or Glass)
Ventilation
Much like with printing in ABS filaments, proper ventilation is paramount if you don’t have an air active filter (like a Zimpure) or an enclosed printer to avoid the buildup of harmful emissions in your workspace When 3D printing it’s crucial to minimise your exposure to VOCs and UFPs. Printing should never occur in front of people or animals. Additionally, food and drink should never be consumed in the same room to prevent ingestion.,
Heated Bed
It is essential that you print with a printer capable of heating to 100°C to slow down the cooling of your part and prevent it from flopping off mid-print.
Enclosure
We recommend always printing HIPS filament with an enclosure. Without an enclosure, warping and cracking during printing will become an issue. You increase your risk of exposure to VOC’s and UPF’sYou may want to consider DIY or aftermarket enclosures if you are using an open build type printer.
Standard Extruder
A printer with an extruder capable of reaching 220°C to 250°C. No special hot ends are required for printing HIPS.
Build Surface
PEI or similar surfaces are recommended as these surfaces keep parts stuck on when hot but pop off when cold. Glass print beds work well too if you don't have access to a build surfaces made of these materials.
Additional Bed Adhesives (Optional)
If you are still having troubles with bed adhesion, you can use additional materials such as bed adhesives (UHU glue stick) or Kapton tape. Think of these as aids, rather than a definitive solution. Often, simply ensuring your bed is level, you have the right equipment and are printing at the right temperatures will ensure your prints stay stuck to your print bed.
For a full list of required equipment and recommended printing temperatures check out our HIPS Quick Start Guide.
Best Practices
In order to print HIPS successfully, ensure you have the hardware setup outlined above. Hardware is only half the battle however. Here are some best practices to ensure reliable HIPS prints.
+ Control Warping
One challenge when printing HIPS is that as it cools from the extrusion temperature to room temperature, the plastic shrinks. While a small amount of shrinking is normally acceptable (up to 0.8% in HIPS) when this shrinking happens unevenly, it is called warping. Similarly to ABS filaments, HIPS is also susceptible to warping. As stated, we always recommend printing HIPS with an enclosure to prevent uneven cooling rates which will likely result in warping. However warping may still occur, even in an enclosure.
If warping occurs during the first few layers of a print, the part will likely separate from the bed, causing the print to fail. This can be prevented by increasing the build surface temperature by 10ºC for the initial layers. This will keep the first few layers hotter, keeping them stuck to the bed.
Doing the same thing with the extruder temperature will also aid bed adhesion.
+ Brim and Rafts
When printing parts in HIPS, adding a brim or raft to your print can help your part stay stuck to your 3D printer's bed.
A brim tells your printer to print several extra rings of plastic around your model for the first layers. This will increase the footprint of your model and the surface area that is in contact with the bed. A hobby knife can be used to trim off the extra material when the print is complete.
A raft tells your printer to lift the model up slightly and print a solid plastic pad (several layers thick) underneath your model. The raft serves a similar purpose as the brim, but is thicker, allowing it to be simply snapped off cleanly from your part when completed. As the raft is thicker than a brim, this comes at the cost of an increase in print time and more material used.
+ Proper ventilation
As we’ve covered, HIPS is known to produce a strong odor, harmful VOCs and UFP’s whilst printing. See: Is HIPS filament safe to print with? If your printer doesn’t have an enclosure or isn’t fitted with an air filtration system, we strongly recommend printing in a well-ventilated area, free from people and pets. To prevent further risk of exposure, ensure the harmful fumes have dissipated before reentering the print area.
For a more in-detail look at the best practices when 3D printing in HIPS, check out our HIPS Filament Ultimate Printing Guide.
Which are the best printers for printing HIPS?
The most effective printers for printing HIPS will feature.
Active Air Filtration
A heated bed capable of heating to 110°C
An Enclosure
Enclosed Printers with Active Air Filtration
While many 3D printers come with a heated bed as standard, features like an enclosure and air filtration are typically only found in printers towards the high end of the market. These include but are not limited to:
Ultimaker S5 (Pro Bundle)
Zortrax 200 (with HEPA Cover)
BCN3D Sigma R19
Tiertime UP300
Raise Pro2 (with HEPA filter)
Enclosed Printers
If air filtration is not a concern, the list of printers grows, and many mid-tier options become available. These include but are not limited to:
Creality CR-5
Ultimaker S3
Flashforge Creator II and Guider II
Zortrax Inventure
Tiertime UP300
Open Build Printers
If an open build printer is what you’re after, the list of possible candidates widens - just be sure to remember to place it in an enclosure for best results. These include but are again not limited to:
Creality Ender and CR-10 Series
Prusa i3 MK3
Artillery Sidewinder X1
Anycubic Mega
Key Takeaways:
Uses
HIPS is a great 3D printing material commonly used for functional, impact resistant parts.
HIPS is soluble in d-limoline which makes it perfect for a investing casting material or for use as a soluble support material.
HIPS is ideal for printing functional parts that must be lightweight, yet durable and impact resistant, however not to the same extent as ABS.
Due to HIPS's unique interaction with d-limoline, it can also be chemically polished.
In addition to smooth polished parts, large assemblies can be made up of smaller HIPS parts by joining it with a chemical solvent like MEK..
Safety
When printing with HIPS filament, safety considerations should be taken into account as HIPS when heated can emit fumes, VOCs, and UFPs, which are hazardous to breathe.
If your 3D printer setup does not have a way to filter these hazardous substances, be sure to take steps to properly ventilate the room before entering.
Setup
The uneven temperature differentials during printing and cooling of HIPS can cause it to warp and crack.
Changes in ambient temperature during the printing and cooling of HIPS parts can cause it to wrap, crack or delaminate.
To print HIPS successfully you will need a printer with an enclosure as well as a heated bed capable of heating to 110°C.
HIPS printing is still possible without the correct setup, but it will be a constant battle to keep prints stuck to the bed, mitigate warping and prevent cracking.
Best Practices
To keep parts stuck to the bed, try increasing the extruder and bed temperatures by 10°C for the first few layers of the print. This will help keep them stuck to the print bed.
Print using a brim or a raft to increase the contact area of the model to the print bed, helping it stay attached to the bed.
