This article will give several printing tips when using Colorfabb Copperfill and will show you the steps and material needed to give it it's beautiful patina finish.

Table of Contents

Colorfabb Copperfill isn’t new, it was released in 2014 and has been one of the more successful speciality filaments. Over the years, people have shifted more and more to post-processing their 3D printed parts to spice up the prints. This is exactly where this material shines (literally), but it will take some work and know-how. If you want to take your prints to the next level with a patina finish, this Colorfabb Copperfill post processing print guide is perfect for you! to get a patina finish.

Colorfabb Copperfill Filament Post Processing Guide Patina Finish — Source: Colorfabb

What is Colorfabb Copperfill?

ColorFabb CopperFill is a high-quality PLA 3D printing filament, loaded with a high amount (80% weight or ~35% volume) of copper particles, specially developed for aesthetic prints. CopperFill shows a real nice reddish glow, just like one would expect from a copper material. After printing, the objects need to be polished, which will result in shiny copper-like objects (but not what you know from copper pans etc).

Some Typical material properties from the datasheet:

Density: 4 g/cm3
Humidity absorption (23ºC,50%RH): %0,3
Tensile Strength: 25 MPa
Flexural Strength: 40 MPa
Flexural Modulus: 7000 MPa
Tensile [email protected]: %3-10
Impact Strength(Izod-Un23ºC): kJ/m2

Due to the weight of the material, there is only 80M filament on a 1.75mm 750g spool and 32M on a 2.85mm 750g spool, at a €49.95 cost. Luckily there are also 1.5kg spools available for €79.94 that are more suitable when doing larger prints and are more cost efficient. Funny enough, the 1.5KG still fits a regular spool!

Copperfill Filament Print Guide And Settings

When printing with a (metal) filled material like Colorfabb Copperfill, some factors are different from what you know from printing with materials like PLA.

Nozzle

You might think printing with these metal filled materials needs a hardened steel nozzle. It doesn’t seem to be the case, because Colorfabb doesn’t mention it in the technical datasheet, while they do for carbon and glow in the dark filaments.

Something I personally experienced is that 3D printing with a 0.5 or 0.6mm nozzle really reduces the chances of getting a clogged nozzle. Also, bigger layers (like a 0.2mm layer height) works great.

Thermal Factors

Another factor is the heat migration within the filament. With Colorfabb Copperfill, this means that heat will travel through filament more efficiently, because of the metal particles.

This results in two things; the Copperfill filament will heat up easier in your hot-end and it will cool down faster when leaving the nozzle. Cooling down faster when leaving the nozzle means excellent performance on overhanging parts This is a big plus for printing busts that often feature overhanging parts.

The fact the Colorfabb Copperfill heats up easier means you can print it at lower temperatures and print with relatively high speeds. In fact, this means you should not print to slow because it can cause problems at the heat break (especially with hotends that use a PTFE tube near the heat break), ruining the print. Keep the flow going!

Friction

When handling the Colorfabb Copperfill filament, some things immediately are noticeable. The material feels a lot softer than regular PLA and can bend very easily, where PLA would just snap. This means you should have excellent support of the filament after the feeder, just like with flexible materials.

The other things are that the Copperfill filament feels a lot rougher than what you are used to with PLA, etc. Although it doesn’t seem to destroy your nozzle, it does cause a significant amount of friction in the PTFE tubes. If you have a large Bowden setup, it might be useful to use a little bit of oil (non-olive) on a sponge to eliminate the friction (during winter you can even get a nice shock when feeding it thru a large Bowden tube). Also, small radii in a PTFE tube toward the feeder can cause so much friction the feeder will just grind the filament.

Support

Because this Colorfabb Copperfill filament is quite expensive, it makes sense to minimize supports, but be careful not to do too little causing a failed print. A nice middle ground could be adding 45 degrees angled support as described in an article on Fabbaloo.

Bed adhesion

This must be one of the easiest materials regarding bed adhesion. It has even less warping than PLA and can be printed on most bed materials like blue tape, Kapton, PEI and glass. A heated bed at 60 degrees is advised, but I personally reduce the temperature after the first layer to 45 degrees.

Flow

Personally, I think this is the most tricky part when printing with Colorfabb Copperfill and needs some tuning. To prevent under-extrusion it might be needed to increase the flow a little bit. This is because Copperfill has less die swell (expansion) when it leaves the nozzle. But just a little too much flow and the excessive material builds up on the nozzle and will end up as a large blob somewhere on your print. This, of course, would create an ugly artefact, but in the worst case it will end up in a failed print (for instance when your nozzle bumps into it and your print tips over).

General Print Settings

Print settings can differ a lot due to differences in hardware and environmental influences, but some good starting points would be:

3D printing temperature: 195 -220°C
Bed temperature: 50-60°C
Cooling fan: On
3D print speed: 40-100 mm/s

Post-processing and creating a Patina finish

Sanding

Now you have your parts it is time to make something extraordinary out of your 3D print! by post processing it to get a patina finish. The 3d printed parts are at this stage probably not what you had imagined, because of its matte look. The first step is to sand it thoroughly. When you print small parts and have a tumbler, this would be a good alternative for this first step, but remember that details can be very fragile.

Start with some rough sanding paper or even better sanding pads (80-120 grid). This will eliminate most of the printing artefacts and print lines. Slowly work up to grid 800-1000 if you really want smooth surfaces. If you just want it to shine, you can start brushing it with a brass brush or rubbing it down with steel wool. Some people use some copper polisher to finish it, but most of the time they smell terrible.

When you are happy with the surface finish, it is time to start with the chemical oxidation to create the outstanding green/blue patina finish. The post processing is fairly simple but is influenced by a couple of factors.

Colorfabb Copperfill finish Oxidation

You only need to apply 3 ingredients on your part to make it oxidate fast. These are vinegar (just use simple white wine vinegar, but you can experiment to get other colors), salt and water. The amount does not really matter much, just make a delightful mixture and apply it to your part.

If you want your part to be completely covered with a patina finish you, use a water spray bottle. When you want just some parts to have patina, to simulate oxidation by weather, you could brush it on. To get a bit more texture you could add some salt on your part locally. Normally your part has permanent patina after 24 hours, but the longer you let it oxidate, the more intense the color will be.

Now you need to place the part in a semi (put the lid on loosely) closed bucket with some ammonia. The best practice is to place a small bowl of ammonia in a corner of the bucket, so it is reusable. Do this in a well-ventilated room, because ammonia smells really bad!

When the oxidation post processing process is done, rinse the part with some water and let it dry. The parts that need to be shiny probably need some brushing again.

To seal this look you can varnish it or give it a clear coat. With a varnish, it will stay greenish, while a glossy clear coat will give it a darker blueish tint.