Do Expensive Filaments Make 3D Printed Wrenches Better?

January 30, 2026 by Donald Papp 45 Comments

What filament is strongest? The real answer is “it depends”, but sometimes you have a simple question and you just want a simple answer. Like, which material makes the best 3D printed wrench? [My Tech Fun] printed a bunch of options to find out — including some expensive filaments — and got some interesting insights in the process.

His setup is simple: he printed a bunch of 13 mm open-end wrenches, and tested each one to failure by cranking on a clamped digital torque meter until the wrench failed by breaking, or skipping.

[My Tech Fun] tested a total of eighteen filaments, from regular basic PLA, PETG, ABS and ASA, and a variety of carbon fiber-infused filaments including PPA-CF. TPU is included for fun, and there’s also a wrench printed with continuous carbon fiber, which requires a special printer. More on that in a moment. First, let’s get to the results!

Unsurprisingly, TPU fared the worst at 0.8 nM which is roughly “unscrewing the cap of a water bottle” territory. Top performers included the wrench printed with continuous carbon fiber reinforcement (failing at 3.7 nM) and a couple printed in expensive PPA-CF (high-temperature nylon filament with carbon fiber) topped the list at 4.3 nM. Everything else landed somewhere in between, with plain PLA surprisingly outperforming some CF blends.

The continuous carbon fiber wrench was printed on a FibreSeeker printer, which reinforces a print with solid fibers embedded into the plastic instead of chopped particles, and such prints are noticeably more resistant to bending. Check out our earlier coverage for a closer look at what the FibreSeeker does.

This is a good time to mention that the wrench 3D model used is not at all optimized for best results with 3D printing. But that’s okay; this is really about the filaments, not the wrench.

The wrench model is just a way to test things in a familiar and highly visual, relatable way. You can see each one in action in the video below, and seeing [My Tech Fun] turn the wrenches gives a very good idea of just how much force is involved, with a relatable display of just how strong the different filaments are.

Continue reading “Do Expensive Filaments Make 3D Printed Wrenches Better?” →

Does Carbon Fiber PLA Make Sense?

January 26, 2026 by Maya Posch 33 Comments

Carbon fiber (CF) has attained somewhat of a near-mystical appeal in consumer marketing, with it being praised for being stronger than steel while simultaneously being extremely lightweight. This mostly refers to weaved fibers combined with resin into a composite material that is used for everything from car bodies to bike frames. This CF look is so sexy that the typical carbon-fiber composite weave pattern and coloring have been added to products as a purely cosmetic accent.

More recently, chopped carbon fiber (CCF) has been added to the thermoplastics we extrude from our 3D printers. Despite lacking clear evidence of this providing material improvements, the same kind of mysticism persists here as well. Even as evidence emerges of poor integration of these chopped fibers into the thermoplastic matrix, the marketing claims continue unabated.

As with most things, there’s a right way and a wrong way to do it. A recent paper by Sameh Dabees et al. in Composites for example covered the CF surface modifications required for thermoplastic integration with CF.

Continue reading “Does Carbon Fiber PLA Make Sense?” →

FibreSeeker 3: Continuous Carbon Fiber Vs Chopped CF

December 25, 2025 by Maya Posch 8 Comments

Although you can purchase many types of FDM filaments containing ‘carbon fiber’ these days, they are in no way related to the carbon fiber (CF) composite materials used for rocket hulls and light-weight bicycles. This is because the latter use continuous fibers, often in weaved CF mats, whereas the FDM filaments just use small, chopped, fragments of CF. Obviously this will not result in the same outcome, which makes it interesting that a company called Fibre Seek is now running a KickStarter for a very affordable co-extrusion FDM printer that can add continuous CF to any part. They also sent a few test parts to [Dr. Igor Gaspar] for testing against regular FDM CF prints.

It should be noted here that continuous CF with FDM is not new, as Markforged already does something similar, though at a ‘Contact us for a price quote’ level. The advantage of the Fibre Seek solution is then the co-extrusion that would make printing with continuous CF much more flexible and affordable. Based on the (sponsored) [CNC Kitchen] video of a few weeks ago at a tradeshow, the FibreSeeker 3 printer is effectively a standard CoreXY FDM printer, with the special co-extrusion dual print head that allows for CF to be coated with the target thermoplastic before being printed as normal.

Continue reading “FibreSeeker 3: Continuous Carbon Fiber Vs Chopped CF” →

Why Chopped Carbon Fiber In FDM Prints Is A Contaminant

December 21, 2025 by Maya Posch 36 Comments

A lot of claims have been made about the purported benefits of adding chopped carbon fiber to FDM filaments, but how many of these claims are actually true? In the case of PLA at least, the [I built a thing] channel on YouTube makes a convincing case that for PLA filament, the presence of chopped CF can be considered a contaminant that weakens the part.

Using the facilities of the University of Basel for its advanced imaging gear, the PLA-CF parts were subjected to both scanning electron microscope (SEM) and Micro CT imaging. The SEM images were performed on the fracture surfaces of parts that were snapped to see what this revealed about the internal structure. From this, it becomes apparent that the chopped fibers distribute themselves both inside and between the layers, with no significant adherence between the PLA polymer and the CF. There is also evidence for voids created by the presence of the CF.

To confirm this, an intact PLA-CF print was scanned using a Micro CT scanner over 13 hours. This confirmed the SEM findings, in that the voids were clearly visible, as was the lack of integration of the CF into the polymer. This latter point shouldn’t be surprising, as the thermal coefficient of PLA is much higher than that of the roughly zero-to-negative of CF. This translates into a cooling PLA part shrinking around the CF, thus creating the voids.

Continue reading “Why Chopped Carbon Fiber In FDM Prints Is A Contaminant” →

Full Scale Styrofoam DeLorean Finally Takes Flight

September 22, 2025 by Tyler August 13 Comments

It’s 2025 and we still don’t have flying cars — but we’ve got this full-scale flying DeLorean prop from [Brian Brocken], and that’s almost as good. It’s airborne and on camera in the video embedded below.

We’ve written about this project before; first about the mega-sized CNC router [Brian] used to carve the DeLorean body out of Styrofoam panels, and an update last year that showed the aluminum frame and motorized louvers and doors.

Well, the iconic gull-wing doors are still there, and still motorized, and they’ve been joined by a tire-tilting mechanism for a Back To The Future film-accurate flight mode. With the wheels down, the prop can use them to steer and drive, looking for all the world like an all-white DMC-12.

The aluminum frame we covered before is no longer in the picture, though. It’s been replaced by a lighter, stiffer version made from carbon fibre. It’s still a ladder frame, but now with carbon fiber tubes and “forged” carbon fiber corners made of tow and resin packed in 3D printed molds. There’s been a tonne of work documented on the build log since we last covered this project, so be sure to check it out for all the details.

Even in unpainted white Styrofoam, it’s surreal to see this thing take off; it’s the ultimate in practical effects, and totally worth the wait. Honestly, with talent like [Brian] out there its a wonder anyone still bothers with CGI, economics aside.

Thanks to [Brian] for the tip! If you have a project you’ve hit a milestone with, we’d love to see it, even if it doesn’t trigger the 80s nostalgia gland we apparently all have embedded in our brains these days. Send us a tip!

Continue reading “Full Scale Styrofoam DeLorean Finally Takes Flight” →

I Gotta Print More Cowbell

July 3, 2025 by Bryan Cockfield 5 Comments

Since the earliest days of affordable, home 3D printers, the technology behind them has been continuously improving. From lowering costs, improving print quality, increasing size and detail, and diversifying the types of materials, it’s possible to get just about anything from a 3D printer today with a minimum of cost. Some of the things that printers can do now might even be surprising, like this upgrade that makes [Startup Chuck]’s 3D printer capable of printing realistic-sounding cowbells out of plastic.

The key to these metal-like prints is a filament called PPS-CF which is a carbon fiber-reinforced polyphenylene sulfide, or PPS. PPS-CF has a number of advantages over other plastics including high temperature tolerance and high dimensional stability, meaning its less likely to warp or deform even in harsh environments. But like anything with amazing upsides, there are some caveats to using this material. Not only does the carbon fiber require more durable extruder nozzles but PPS-CF also needs an extremely hot print head to extrude properly in addition to needing a heated bed. In [Startup Chuck]’s specific case he modified his print head to handle temperatures of 500°C and his print bed to around 100°C. This took a good bit of work just to supply it with enough energy to get to these temperatures and caused some other problems as well, like the magnet on the printer bed demagnetizing above around 75°C.

To get to a working cowbell took more than just printer upgrades, though. He had to go through a number of calibrations and test prints to dial in not only the ideal temperature settings of the printer but the best thicknesses for the cowbell itself so it would have that distinct metallic ring. But cowbells aren’t the only reason someone might want to print with carbon-reinforced materials. They have plenty of uses for automotive, chemical processing, high voltage, and aerospace applications and are attainable for home 3D printers. Just make sure to take some basic safety precautions first.

Continue reading “I Gotta Print More Cowbell” →

Random Wire Antenna Uses No Wire

November 5, 2024 by Al Williams 40 Comments

Ideally, if you are going to transmit, you want a properly-tuned resonant antenna. But, sometimes, it isn’t practical. [Ham Radio Rookie] knew about random wire antennas but didn’t want a wire antenna. So, he took carbon fiber extension poles and Faraday tape and made a “random stick” antenna. You can check it out in the video below.

We aren’t sure what normal people are doing with 7-meter-long telescoping poles, but — as you might expect — the carbon fiber is not particularly conductive. That’s where the tape comes in. Each section gets some tape, and when you stretch it out, the tape lines up.

Continue reading “Random Wire Antenna Uses No Wire” →