You’ve mastered the basics of 3D printing, and now you’re looking for something more interesting, more challenging. You’ve run the gamut of materials, know exactly how to fine-tune your temperatures, and have your computer-aided drafting game down to an exact science. You’ve even impressed your friends and loved ones with tasty chocolate creations they never thought were possible to get from a machine.
Where do you go from here? Dive deeper into the science of your process by 3D printing with carbon. It may sound intimidating, but guess what – it’s so much like 3D printing with any other materials, you’ll be a genius at it in no time. We’re here to help you find exactly what you need to know to get started, including how to find the perfect equipment to get the best results available from this wonder material.
Carbon itself is the building block of life. Its abundance (as the fourth most common element in the universe) and its unique ability to form polymers at common Earth temperatures makes it super versatile. You see examples of it every day from the graphite in your pencils to the diamonds in your jewelry. Carbon’s isotopes – the different kinds of materials it forms when bonding with other molecules – are all highly resistant to chemical reactions, requiring high temperatures to react even with oxygen.
Uh oh, you’re thinking. My 3D printer doesn’t sound like it’s up to that challenge. But don’t worry – the material you’ll be working with is a mixture of carbon and thermoplastics, designed to perform perfectly in the 3D printing process. Carbon filament is blended with those thermoplastics to make sure it can be melted to just the right consistency for the type of weaving manipulation your printer’s extruder will be doing.
And there are a lot of advantages to printing with carbon filaments. Here’s the rundown:
Carbon 3D Printing Pros and Cons
- Carbon fibers in filaments make the material extremely strong and stiff. That also makes them much lighter and more dimensionally stable, which means they won’t experience the shrinkage that’s typical of many 3D printed materials once they cool off. The carbon fibers in the filament help with that, holding the shape of the form better than PLA or ABS on their own.
- You don’t have to fiddle with your printer settings or memorize any other special settings just for carbon mix filaments. They’ll work with all your standard temperatures – that’s the thermoplastics molding the carbon’s behavior for optimum performance in the specific environment of a 3D printer.
- On the other hand, carbon mix filaments are extremely brittle. That means you have to be careful during the time between when it finishes printing and when it cools down enough for its intended use. It also means you have to be careful getting your finished project off the printing bed; let it cool down completely before you attempt to get it off because otherwise, you risk cracking it. That sounds counterintuitive based on the strength of carbon filaments, but its strong resistance to shrinkage means it doesn’t have much give at all, and give is what makes other filaments easier to manipulate. So be careful when you’re moving your carbon filament creations off the printer and into the real world.
- The same stubborn properties that make carbon great for strength and structure take a toll on the 3D printer you with it. The brunt of that abuse is taken by the part that spends the most time manipulating the filament. Because of its abrasiveness, carbon will tear up your extruder if you don’t take the right precautions. The stiffness in its fibers will scratch the inside of your nozzle as well as clog it pretty heavily, even when mixed with the more pliable thermoplastics that form the basis of those filaments. Make sure your rig is ready for all this before you start experimenting, or your 3D printer will be useless and unresponsive by the time you’re ready to get serious.
- Another danger of using carbon mix filaments in an unprepared 3D printer is the oozing. Because carbon filaments contain a lot of small fibers that won’t melt at the extruder temperatures, they’ll clog the nozzle as we talk about above, and a clogged nozzle means weird patterns of tinier holes for the part of the filament that does melt to leak out of and go anywhere except in the pattern you want. If you’ve ever tried to get frozen yogurt or soft serve ice cream from a pump that’s struggling to deliver your treat, you’ll get the idea of how a 3D printer nozzle clogged with carbon can splutter out an unwanted mess if you don’t take measures to prevent that.
If you’re now thinking that printing with carbon filaments sounds like more trouble than fun, don’t let us discourage you. Carbon is a great material, and fortunately, there are easy, definite, and affordable measures you can take to make sure none of these cons mess up your 3D printing experience with carbon. Here are some tips on what you can look for, what you can add, and what you should make sure is in place before you begin your journey with this fussy but worth its molecule.
The Printing Process
You don’t need any specialty 3D printer to use carbon filaments (although really cool strides have been made using carbon to do the printing itself), you just need to look for these specific traits to make sure they’re available in the equipment you’re looking at. If you’ve already got a 3D printer and don’t want to get a whole new one to accommodate your new filament, you can make modifications to your current rig, too – those are sold as separately as you need them, and a few are just settings you can change without learning or buying anything new.
Whatever your level of expertise, you’ll be able to buy, find, or adjust however you need to work with carbon, and you’ll be reaping the rewards for as long as you need them.
- Make sure the printer you want to use has a heating bed temperature of 45 – 60 degrees Celsius. You don’t have to use an enclosed heating area; an open one will actually help your creations cool down a little faster, so don’t worry about that part. The heating bed temperature is an important detail.
- Extruder nozzle temperature of 200 – 300 degrees Celsius. This is pretty standard for any of the base filaments that you will find mixed with carbon, so you will likely not need to look for anything unusual in this area.
- However, you DO need to make sure you get hardened steel nozzle. A lot of the time, the carbon fibers in the carbon mix filaments is harder than the brass nozzles that are the typical finished surface for most 3D printer nozzles. Trying to print with stock nozzles could, therefore, cause irreparable damage. So upgrading to a hardened steel hot head will prevent that from ever becoming a problem. But hardened steel nozzles are also less heat conductive than brass, so in order to compensate for that AND keep your hot head from getting scratched, you may have to increase your nozzle temperature as much as 40 degrees Celsius. Check the specs for your hardened steel head and that will tell you the adjustments you need to make.
- Alternatively, you could use your part cooling fan. This is another necessity while using carbon filaments because you’re dancing on a fine line between temperature manipulation and keeping your surfaces safe from that abrasiveness so common in carbon fibers. This is also an easy part to add to your machine; some 3D printers even come with instructions on how to print that as your first project. To counteract the lesser heat conduction of your hardened steel nozzle, you can run your part cooling fan slower to help the filament flow easier.
- Yet another adjustment that makes the extruder’s job easier with carbon mix filaments is increasing the nozzle diameter. 0.2 mm – 0.4 mm is the most common size range, but anything between those parameters will encourage more clogging than is practical to deal with in carbon filament printing. Bump up your nozzle diameter to 0.5 mm to drastically reduce the chance you’ll have to deal with this issue. Since the unmelted carbon fibers have a whole extra millimeter to move, they’re much less likely to clog. It doesn’t sound like a lot, but anyone who’s dealt with 3D printing knows it’s the tiny details that count.
- You also need to check your retraction settings. Since the carbon fibers in your filament won’t melt and you need to keep a close eye on any clogs, reducing your retraction distance – or even eliminating it altogether – can reduce the distance in which a clog can build up. Less distance means less tubing for the filament to move through, which means it has less time to slow to a stop and clog everything. And 3D printing companies are already on this issue – the Simplify3D brand has a setting that lets the nozzle stay within the interior area of the extruder so there is little to no retraction. All you have to do to turn this on is go into your advanced settings and turn on the “avoid crossing outline for travel movements,” and many other printers will have the same option somewhere in their settings. Look at the user’s manual online before you buy to make sure the model you want has this critical feature.
- If the nozzle still seems to clog on you immediately (after the first layer or two), try changing your layer height. If it’s too reduced for the first layer, the nozzle may be close enough to the printing bed to cause back pressure that can cause the fibers to build up and clog because they don’t have enough space to get out.
- Additionally, slow your print speed down for more consistent results. A slower print speed puts less pressure on the nozzle, and if small clogs start to form, the extruder will be more likely to be able to push them through before they get big enough to cause issues. Reduce your print speed by anywhere between 25 and 50%, and watch your results to make sure they’re getting better.
- One more way you can ensure your carbon fiber filament has the easiest time possible getting through your printer is to make sure you use a guided filament path. The carbon fibers in your filament rub against every sharp turn and corner you have between your spool and extruder and the element’s brittleness can cause it to snap on these types of edges. If you use gentle curves instead, you’ll keep your carbon filament intact and its flow smooth to where it really needs to go – onto your project. You can find PTFE guiding tubes specially made for this, or you can get a 3D printer that has a short, straight, direct path from its spool area to its extruder.
The Best Products
Now that you know all about what to look for in a 3D printing set up that you can use for printing with carbon filaments, here are the best rigs we’ve found to help you set it up.
- Matter Hackers makes a huge range of 3D printing nozzles that give you a great range of nozzle diameters as well as finishes that are great for working with abrasive materials. Their prices vary and let you experiment without breaking your budget or needing to find space for a whole new machine. They even offer a “pro pack” of six different nozzles, all up to carbon printing standards, and the tools to switch them out.
- Instructables has a great tutorial on how to add a parts cooling fan to your 3D printer. You can find this starting at under $10 on Amazon – just make sure to read the reviews before you buy to ensure you’re getting what you need for your specific types of projects.
- Prusa Research offers a selection of quality 3D printers that either already has larger printer nozzle diameters, or are fitted to accommodate them.
- Fusion3, RoboxPro, and MarkForged all offer 3D printers that are built inside and out to deal with strength printing from tough filaments like carbon. They vary in their specifics and price ranges (although prepare to pay more than what you would for a printer not optimized for special material), so you can find your perfect match when you want to start from scratch.
Looking for a way to easily print with carbon filament is not as difficult as its reputation. If you’re looking to add carbon filament to a 3D printing business or hobby that’s already active, you can modify your current machines to accommodate; if you’re just getting into the game and want to jump right in with carbon filaments, you’ve got lots of choices for printers that give you everything you need in one place. We recommend easing in and seeing what works best with your personal preference – try it, you’ll like it!