3D Printing Filament Material

CONGRATULATIONS! You have joined the world of FDM 3D Printing and you are all excited to get printing.  Well just hold on there a second.  We need to have a little chat about FDM Filament.  By now you’ve probably seen the plethora of FDM filaments available.  But what is PLA, why is PTEg a thing and you all want to know if you can use Nylon with your 3D printer.  All your questions will be answered in this blog.  I’ll keep it short for you while trying to get the most important information across.

Ready? Let’s jump straight in.

Before I start talking about the types of filament, let’s lay down some simple rules.

1.       ALL FDM filament is hydroscopic is one way or another, that means it absorbs water from the air.  You are advised to store your FDM filament spools in an air tight container with the ‘silica gel’ packs it was supplied with.

2.       Get used to loading and unloading filament from your printer.  If you’re not printing for a few days, then unload and store the filament.  Doing this really does save in the long run.

3.       Not all FDM filament is the same.  Please DO NOT use cheap unbranded filament.  You get what you pay for and cheap filament ALWAYS ends up in the bin, usually after hours of failed prints and frustration.

4.       Choose the right filament for the right job.  Making a ridged bracket? Flexible or Nylon aren’t a good choice.  Want to make a clip that has some give?  PLA won’t be good for this.  FDM printing does not have a “one for all” filament solution.

Now that that’s out of the way, let’s talk about the different types of FDM filament available.

PLA

Polylactic acid, or PLA to the rest of us, is probably the most popular FDM filament.  It is very easy to print with PLA.  It prints at a lower temperature than other filaments and is more resistant to lifting and warping.  It can be used without a heated build platform, but having one does help. PLA does not produce any offensive smell during printing. It is considered “odourless”, but some people say it smells like popcorn when printing.

PLA is also used as a base material in many other filaments e.g. metal filled, wood filled and glow in the dark filament.

PLA Properties

PLA Applications

PLA is quite brittle, so items that are under bending or twisting loads can fail in a very energetic way.

PLA will destabilise at 60°C and above, remember this if your printed parts are going to be used with hot liquid.

Commonly PLA is used for prototype parts and space models.

ABS

Acrylonitrile butadiene styrene, or ABS as we all know it, may well be the second most popular FDM filament, after PLA.  ABS is actually superior to PLA, despite being slightly more difficult to print.  ABS can be found in many household products, the most famous of all is LEGO bricks, we’ve all stood on those tiny bricks in our time.  It’s strong stuff.

Unlike PLA, ABS prints will withstand high temperatures but it must be printed at a very high temperature.  This can cause the print to warp it gives off very offensive fumes while printing. ABS requires a heated build platform and should be printed in a well-ventilated area. ABS prints better in a fully enclosed FDM printer as this has a higher internal ambient temperature.

ABS Properties

ABS Applications

ABS is tough stuff.  It is able to withstand high stress and temperature.  It is also a little flexible, depending on the size of the printed section.  It does turn white around any high stress areas though.

Commonly ABS is used for tool handles, automotive trim and manufacturing jigs.

PETg

Polyethylene terephthalate, or PET, is THE most commonly used plastic in the world. Well all know it as the material used to make water bottles and food containers.  Raw PET is rarely used in 3d printing but it’s variant, PETg, is a popular FDM filament.

The ‘g’ in PETg stands for “glycol-modified” which makes a filament which is clearer, less brittle and easier to use than base PET.  PETg is considered as “between” between ABS and PLA because it is less brittle than PLA but easier to print than ABS.

PETg is very sticky during the FDM process.  This makes it a bad choice for support material, but it has very good layer adhesion.  Be careful with the first layer height on the build platform, you have been warned.

PETg Properties

Commonly PETg is used to make mechanical parts and protective components.

Nylon

Nylon is often referred to as the “Number one” FDM filament when looking at strength, flexibility, and durability.  Many grades of nylon exist, the most common Nylons in FDM filament are Nylon 618 and Nylon 645.  Nylon does not like to stick to the build platform.

Often an interface layer of PVA glue is required on the build platform. Some FDM printers are unable to reach the required print temperature. For these printers a ‘Bridge’ Nylon product exists.

Nylon Properties

Nylon Applications

Nylon has great strength, flexibility and durability.

Commonly Nylon is used to create jigs or mechanical parts (e.g. hinges or gears).

TPE

Thermoplastic elastomers, or TPE or Flexible filaments, can be described as plastic with rubber qualities.  These filaments are unbelievably flexible. As such, TPE is commonly found in automotive parts and household appliances.  Be warned, TPE is like NO OTHER FDM filament.  Even on the spool it is very soft and flexible.  It is printed VERY VERY slowly and some printer setups can not print TPE at all.

TPE Properties

TPE Applications

TPE can withstand repeated flexing and stretching.

Commonly TPE is used to create grips, shock absorbing mounts and belts.

PC

Polycarbonate, or PC, is possibly the strongest FDM filament listed here.  It has very high durability and is resistant to impact and heat.  It can withstand up to 110°C. Clear PC is used in items such as diving masks and display screens.

PC Properties

PC Applications

PC has great strength and temperature resistance making it ideal for mechanical or automotive components.  It’s optical properties make it a good choice for lighting diffusers etc.

ASA

Acrylonitrile styrene acrylate, or ASA, is a variant of ABS.  The big difference with ASA is that, where ABS “yellows” and becomes brittle with exposure to the elements, ASA does NOT.  When flexed, ASA does not turn white at the point of highest stress.

ASA Properties

ASA Applications

Anything you want to make that’s going outside.

PVA

Polyvinyl alcohol, or PVA, is soluble in water.  That’s it, it melts in water.  That’s exactly what it does, so what’s the FDM use for it?  Dual head FDM printers use PVA as a support material when printing shapes that can’t be printed.  As you can imagine, PVA needs to de stored in a DRY place, or it will melt.

PVA Properties

PVA Applications

PVA filament is often the only choice of support material when printing parts with impossible features and / or shallow overhangs.

Carbon Fibre Filament

This type of FDM filament blends carbon fibres with a base material.  PLA, ABS, PETg and Nylon can all be filled with carbon fibres.  The resulting FDM filament is extremely stiff and ridged.  Sounds great really, BUT……………FDM printer nozzles are usually brass.  Carbon fibre filled filament will wear out these brass nozzle FAST.  Tests show that printing just 500 grams of carbon fibre filament will damage the brass nozzle.  Hard coated nozzles are available, but not for every FDM printer.  Please check with your printer manufacturer before using carbon fibre filament.

Carbon Fibre Filament Properties

Carbon Filled Applications

Having high strength and low weight, carbon fibre filament stands alone for mechanical components.  Be warned, it destroys brass printer nozzles.

I hope this list has given a better understanding of FDM filament and you can now select the correct material for your application.  All these materials are available from SolidPrint3D.  If you require any further information, please get in touch.

This article was originally posted on our sister companies blog: Solid Solutions