E3D Introduces Tool Changing 3D Printer

E3D has introduced their latest answer to multimaterial printing at the Midwest RepRap Festival this weekend. Their research project into a 3D printer with the ability to change toolheads is the latest advancement in multimaterial printing. It’s a work of engineering brilliance, and they’ve already written up their teardown on how this all came to be.

While milling machines and other fancy industrial CNC have had tool changing for decades, and the subject has been pursued by the RepRap community for a few years now, it really hasn’t caught on. The question then is, what is tool changing on a 3D printer good for? The answer is multimaterial printing, and doing it in a way that doesn’t have the downsides of current methods of printing with multiple materials.

There are three current methods of printing in multiple materials. The first is putting two nozzles on the same extruder, but this has the downside of one nozzle interfering with the other. The second is pushing two different kinds of plastic through the same nozzle, such as in the E3D Cyclops, or Prusa’s multimaterial upgrade. This has the downside of cross-contamination, and you can’t print in materials that require different temperature profiles. The third method is simply using multiple carriages on the same machine, such as the lovely stuff from Autodesk or Project Escher. This last method is horrifically complex.

The answer the problem of multimaterial printing is hot-swapping toolheads, but to do this you need precision and repeatability. The folks at E3D have been working on this for years, and I remember seeing some experiments with electro-permanent magnets a few MRRFs ago, but now they finally have a solution. The answer is simply a cam that’s turned by a cheap hobby servo. This is kinematic coupling that allows the carriage to clamp onto a toolhead with 5 μm precision.

Right now, E3D’s experiments in toolchanging 3D printers have culminated in a single 3D printer featuring their toolchange carriage, four toolheads, some amazing linear rails, and a CoreXY configuration. The prints that are coming off of this printer are spectacular. There are four-color Benchies, and the drivetrain of a remote-controlled car with gears printed in Taulman plastic and a driveshaft printed in ABS. The car was a single print made with multiple hotends, demonstrating most of the problems of multimaterial printing disappear with the E3D swapping toolhead printer.

If you’re interested in purchasing one of these printers, E3D currently has a survey for potential buyers and a deposit queue for any future purchases.

40 thoughts on “E3D Introduces Tool Changing 3D Printer

  1. Nice. I thought of something very similar about 3 years ago; core xy, swapping heads, using magnets and/or servo to capture the heads, but never had time to pursue it. I didn’t like all the mixing/multiple/train track designs. Though I had the extruder motor mounted on the X carriage – I hate long Bowden tubes too!

  2. didn’t Prusa also announce they were going a different route for multi-material ? I vaguely remember getting a mail about it.. havn’t ordered the multimaterial yet because of that announcement..

    1. It produces really nice results but wastes a lot of material. It creates a purge block or tower which has to be kept built up to the same height as the rest of the print, so it’s going up even when you are printing the same color for many layers.

      What it needs is a waste chute and nozzle wiper so for color changes it only has to move the head over the chute and purge when colors are changed instead of wasting huge amounts on the block *all the time*.

      1. The same method is used in Stratasys F123 series. It wastes material but gives nice results with simple design. If Stratasys does it then why not Prusa. F123 even has special place on the build plate for the purge block. It also builds massive raft to deal with bed leveling problems.

  3. I’m not downplaying the E3D achievement but Frank Herrmann has been doing the same thing but without the reliance on the servo. I sent it to the tips line but it didn’t get featured AFAIK. I suggest anyone who is interested in the E3D system should consider Frank’s approach and perhaps offer to collaborate with him on an OSH version. No need to wait or pay for E3D to to make you one.

      1. I did. They said “Toggle locks and permanent magnets
        Alluringly cheap, but had the bad habit of conflicting with precision locationing. They also require a space-consuming sideways movement (resulting in fewer tools per machine).”
        My understanding of Frank’s approach is that repeatable location accuracy is acceptable and the space required for the removal wedge/system is not an unreasonable percentage of that required for a different tool head. You may disagree. Just because E3D weren’t happy with the ways they found to use permanent magnets doesn’t mean the technology should be written off by others. I like E3D and have their gear in my printer but a cynic might observe that it would be harder for E3D to sell you a tool changer system you can make yourself. Just drawing attention to some alternative approaches, related to the topic of the post.

        1. Their system looks like I could make it myself, that lock just needs to be a little bigger. You can achieve the same accuracy with magnet and wedges like theirs, but magnets have one drawback – you need bigger force for separation than for holding so you can’t have too strong magnet. With lock you can use less force and it won’t require you to pull with carriage.

    1. Your wording could be interpreted to mean that E3D’s machine is closed source, which is true though only temporarily. E3D said they will open source it. They tend to open the sources after release.

      1. You could read it that way, true. Some people might like the opportunity to have more influence over the design by offering to collaborate with an individual, rather than a company, and that’s what I was probably getting at. Regardless of OSH, there will be clones in the not too distant future, if it’s a successful approach from E3D. It’s all moving forward though.

  4. So this lets you go from one extruded material to a different material or color? Still point based, still limited by the fundamental materials and the fact still remains that prints are extremely slow and fairly low resolution overall.

    I guess this is a potential improvement for this style of 3D printing provided it blends together well enough but why is everybody still seemingly toying around with this style of 3D printing when there are considerable (patent free now!) numbers of alternatives that are materially better out there?

    1. Imagine for a moment adding a gripper head that can place captive nuts, a laser engraver head, or even a powder coating head, an EDM milling head. Multimaterial is just a easy to demonstrate (and monetize) benefit of a general purpose toolchanger but if you read about what they are actually trying to accomplish with this there is so much more to it. If you want fast, amp up a laser printer scan head so it can cut paper and use full page width print heads to apply colors and glue. Just as fast as a normal printer can pass a ream of paper you have your print.

      1. This feels like a machine that *can* technically do a lot but is regrettably poor at doing most of them. I remain skeptical that the machine can eventually actually achieve all of these things, do a great job of all of them and still be reasonable price wise. It’s like scissors that doubles as a tape measure, lighter, paring knife and knife sharpener. You are usually better served with dedicated, purpose built tools unless there is a compelling reason or advantage to not doing so.

        1. After thinking about this for a bit, I realized that when framed a little differently your example may argue for, rather than against, a toolchanger. Each head can represent a specialized tool that excels at one job. So now the hypothetical machine has an actual set of scissors, tape measure, lighter, etc… that it can apply to the task rather than a “master of none” widget. More concretely, the availability of commercial off the shelf automatic toolchangers provides evidence that they enhance CNC operations in a tangible way.

        2. This effectively is a technology demonstrator, and this is what E3D is about to sell, they are not selling you a finished printer, but a way to play with this head changing technology.

    2. “Materially better” how? The results may be better, but how much time/effort/money do I need to invest to go that way? It doesn’t help if a result looks better but costs 10-100x the time or money to produce. If current consumer FDM systems give you ‘good enough’ results, then the extra costs of the alternatives are wasteful.

    3. Slow and low resolution compared to what? Not to mention the price point. I have used several other methods of 3D printing via the Shapeways service bureau. The equipment that they use costs upwards of 10s of thousands of dollars, over 250k for sintered nylon. All three of my printers (two Anycubic Kossel Deltas and a Prusa i3 MK2S) together cost about $1300. I use them on an ongoing basis to produce same or next day engineering prototypes, fixtures and other useful tools that simply wouldn’t be available to me in the same time frame or price point with other methods. This tool changer design from e3d is one of several incremental improvements to entry level 3D printers that make them a valuable tool in my shop.

    4. Specifically which other printing technologies are you talking about?

      Powders and resins cost more per unit volume and I think it’s arguable that powder and resin materials are less home-safe.

      I don’t think there’s a panacea type off 3d printing, and the E3D guys are playing to and expanding on what they know.

  5. It’s great to see work being done on this, multi-material is the future obviously, and this project looks really interesting. The multi-colour prints look amazing. However, when I look at prints like the tugboat with it’s portholes and door arches, I can’t imagine how long they take to print.
    I think we still need advancements in tool-path generation algorithms, and another axis or two. For example, imagine printing the whole cabin of the tug, rotating the object so the porthole is flat to the printer’s Z-axis, and printing the orange porthole in one go.

      1. It’s hard to say where the problem is but I don’t think they’re misrepresenting the slides and belts. The photos in the presentation clearly read HiWin.

        I don’t recall noticing the markings on the belts but they did say it’s the Gates low dust type belt and those do look a little bit different than their standard PowerGrip GT. I think it’s the “Carbon” line.

        They aren’t running the toothed side of the belts over toothed idlers and I think that’s part of the problem. Whether they haven’t really tuned out the motion or if there’s resonance, I couldn’t say. It looked pretty good in person.

    1. As a master of poor print quality, I recognise some of those patterns on the print walls as similar to what happens if I really go for thin walls, especially if the filament temperature is at the higher end of its range. When the infill periodically meets the walls I get the vertical ribbing. Thinner walls with fewer perimeters = faster prints though, so it’s sometimes an acceptable trade-off.

    1. It almost made me laugh – they basically describe multiple tool head 3D printers in a very general way (which I thought would be the preamble to a specific invention) and then stop! They may have well started at the other end and said it’s a cnc router tool head changer. As long as it has three axis motion and at some point you do filament extrusion, it looks like you’d breach it. They seem to have potentially limited the definition of the controller as using CAN bus. Not sure if this can be a general term or if it’s a potential loophole for non-CAN bus controlled machines.
      They are trying to patent a concept, rather than an invention in my ignorant opinion. Doesn’t look like they’ve applied in Europe though. Perhaps we have our own hilarious application pending. Perhaps E3D are fully aware of the patent situation and that’s why this is all being talked about as R&D at the moment.
      Would *love* to see HaD get one of the Supplyframe contacts in the patent world help them do an article on how to read patents with a view to continuing your own work without breaching them. This would be an excellent case study.

      1. While I’m not endorsing it in any way (as a matter of fact, I hate patents), but I think that everyone who develops these kinds of things should be aware that it exists.
        And yes, that patent is extremely broad, but those are the really scary ones. Such broad patents have been approved in the past, and those are generally very dangerous territory. Should your company invest in develop a technology and hope you don’t infringe on any patent due to a broad interpretation of it or should you go for a another, worse solution and have a safer way? It’s a huge challenge, that I deal with very often at work.

        But yes, I would really love a HaD article (or maybe article series) on patents. Like how to read them, what to do if you might infringe, what your options might be.

          1. There are multi-tool head patents going back to 1999 and further but people need to start filing challenges so that we don’t end up with more retarded patents. You have people applying for patents for stuff that has prior art in the 90s.

  6. Another alternative for multi-materials/colors is that taken by Mosaic with the Palette, which splices filaments and uses a single hotend. Also dual hotends can be fixed (leading to problems) or you can raise one of them when not in use. The BCN and Leapfrog Bolt also have independent toolheads which park at the side (or move in tandem), which is another alternative. FDM may not have the highest precision, but you cannot make multi-color/material objects with DLP or SLA.

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