Portable 3D Printer Gets Even Smaller, Faster, Better

How do you improve on a fast, capable 3D printer that sports an innovative design and is portable enough to fit in a printer spool box? Judging by what went into the Positron V3 portable printer, (video, embedded below) it takes a lot of hard work and an unwillingness to settle for compromise designs. Plus a few lucky breaks and some design wizardry.

When we first reported on [Kralyn]’s innovative “Positron” printer, its chief selling points were its portability and unique layout. With a fold-down Z-axis and a CoreXY-style drive in the base, plus an interesting 90° hot end and transparent heated build plate, the Positron managed to hit most of its design goals. But there’s always room for improvement, and Positron V3, shown in the video below, has made some pretty substantial leaps over that original concept.

The V3 design keeps the basic layout of the original, but greatly improves the usability and portability, while increasing performance and build volume. The heated borosilicate build plate is now held to the Z-axis drive with a much sturdier strut, and gets its juice through a high-temperature MagSafe connector. The X- and Y-axes are now driven by pancake steppers, which along with adding idler pulleys that are coaxial to the drive pulleys, make the CoreXY drive, and hence the printer’s base, much more compact. The printer is still much, much faster than most traditional gantry design, and print quality is on par with anything available commercially. And yes, it still fits into a standard 1-kg filament spool box when folded up.

We love this design, and the story of how the V3 came about and the intermediate V2 that didn’t make the cut is a fascinating case study in design. And as a bonus, [Kralyn] will open-source the V3 design, so you can build your own as soon as he releases the files.

[Andrew] tipped us off to this one. Thanks!

35 thoughts on “Portable 3D Printer Gets Even Smaller, Faster, Better

    1. The author said he cant sell kits or assembled units so he’s open sourced the entire design so you can build one yourself. The biggest problem though is a number of parts require cnc/milled metal parts which wont be cheap to get manufactured in small quantity (especially if you just wanna build one for yourself).

        1. The ones I am particularly talking about are the bed support arms and the hot end heater block so they specifically need to either be thermally conductive or very sturdy under heat in order to reliably and accurately work.

      1. There are some parts, such as the hot end and the PCBs, which would be a lot of work to DIY one-off. I think that he’s hoping that one or more 3D printer companies start mass producing and selling these printers, a bit like how Ender took open source designs and started cranking them out. That being said, it won’t be cheap – synchromesh costs much more than standard belts, etc., but people are willing to pay more for better… and this design gives the advantages of CoreXY in a really tiny printer with a decent print volume, which is a nice combination. I’d buy one.

    2. Yeah, my € too! I live in a small appartment where I basically can not leave anything unboxed, and large set-up and repacking time has been my main blockade for getting a 3D Printer

      1. Have you looked into the Voron V0.1? It’s pretty compact, and a fun (if challenging) build. The Prusa Mini is probably more practical, and cheaper, but not nearly as fast.

    1. If LDO can make a buck doing it, they will. I hope they do.

      This a great new take on 3DP, portability 8s a novelty but open it up for more people to use it in more places. Kudos on the design concept.

    1. Though can you imagine geeks trying to get engaged, one of them gets down on one knee, pulls out a small velvety looking box, flips it open, “Wait a minute, it’s gonna print it” bzzzzt bzzzzt “heh, just take a liiiittle while” bzzzzt bzzzzt …. 2 hours later “Mawwiage?”

  1. Depending on how much the off the shelf portion of the BOM is, I might have another project for myself. It’s a pretty slick concept, and while I don’t need the portability aspect of it, the speed and novelty factor are definite interests.

    (I’ve been wanting to dink around with Klipper, but don’t want to nuke the firmware on my existing (and only) 3d printer quite yet- I’ve already gone out on a limb with the community edition firmware, which is head and shoulders above the stock firmware.)

  2. I think this is a really great idea. Not so much because of the portability, but because it’s easy to stow away when you don’t use it. I don’t have enough space in my lab to have a 3D printer, and my wife was clear that she would not allow anything to ‘spill over’ into the rest of the house. ;) So having one that can be folded and stowed away would be a super solution for me.

    1. Maybe someone did their Homework and looked Around The World and hoped they would Get Lucky and find something suitably Technologic to be sure they were Doin’ It Right.

    1. @ MW said: “Hopefully the files will be released soon.”

      For all the design files go to the GitHub page, not GRABCAD:


      The GRABCAD page is really useful for quickly looking at the parts in their 3D viewer, but you cannot download files from GRABCAD without signing up for an account. Use the GitHub page instead for downloads.


    1. Love it. I can’t have “normal” 3D printer sitting around taking up a lot of space. I would buy one today, if I could. I hope Hackaday will followup on this story when someone (hopefully) signs up to build these commercially.

      1. Bit out of nowhere and a long time later. But supposedly LDO is working on a commercial Positron V3 kit nowadays. Considering LDO motors already makes pretty good Voron kits. a LDO Positron would thrust the printer into widespread availability for any wanting to build it.

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