Arc clone - finished.

  • Hey,

    you probably watched that "arcduino" thread, where I wrote about my progress with an arc clone.
    The clone is finished now and in a working condition, although its firmware could need some polishing. I'm not aware of any bugs so far.
    It uses the original push-button encoders of the first arc batches and is perfectly recognized by serialosc.

    You can find all my sources and some images + general info here:

    Oh and please only attempt to build one, if you know what you're doing. Buying one isn't much more expensive at all and saves you a lot of headache.
    Cheers and let me know, what you think!


  • Wow! Nice work.

  • Do you have anything like an eagle file to work with?

  • Good work!

  • Definitely. I've been tracking you since you started. I must say this is remarkable. I was going through all of the files... and pardon my ignorance, but is there a parts list somewhere as well?

  • Ah, there is no parts list, but I have a (partly incorrect) order sheet from mouser (where I got the components from). I could upload it, but I don't have the time to go through all of them and check the mounting sizes. I know that some of the resistors of my order where in a far too tiny package (0402 or even smaller)...

    Eagle can output part lists, can't it? I'll put that on my to-do list for the next days...

    @tanais, I didn't upload the eagle files to stop someone from using them to go into a mass production. I know - you could still extract the gerber data from the pdf files... But in the end you might be faster doing a complete redesign...

    PM me with a mail address and I'll send them to you.

  • Well, I think I won't offer detailed instructions or "how to flash the firmware" guides. For someone, who just wants an arc a bit cheaper but who has never even used a soldering iron, this project won't be much fun at all. Offering too many instructions might push people to start something they can't finish without massive help.

    Don't get me wrong here: I would encourage anyone to try it but only if there is a resonable willingness to get into the details and to work out some of the problems that will appear along the way.
    I will always help if I can! So feel free to contact me!

    I actually hope to see people messing around with this and creating some unconventional control surfaces that follow the arc protocol. That would be great to see! My solution is working well but there is still room for improvement.

  • Hello, correct me if I am wrong: are you planning to sell the clones?
    or is it just your personal excercise to have built one?

    I cannot see on your website any reference to this so it is why I am asking.


    Anyway great job!!!

  • No, this is just for fun. Better buy real arc from tehn.

    To be honest: I wanted a cheap arc for myself in the first place, this is how it started. But as it soon turned out, building one is not much cheaper at all.
    In addition I wanted to create an open source realization of the arc to enable people to modify it and create their own interesting stuff.
    So if you want a custom arc then my stuff could be helpful for you.

  • great thanks for the answer.
    I agree that buying is best for the original but the customisation is intriguing.

    THanks for sharing

  • I am thinking of making an ARC in a 2 x 2 matrix rather than as a 1 x 4 strip/slab, if that makes sense... or perhaps start small and have a single or two ARCs built into my Stribe 16 I am presently rebuilding, resurrecting from an accident, hence my interest

    @TheSlowGrowth I'll drop you an email I'd love to have a go at customising

    I agree the eagle data would be an invite from someone to mass produce...

    850 x 1280 - 196K
  • Hi tanais,

    Wow, that looks like a massive stribe :-D
    Good luck with the project! Keep me/us updated!

    I'll try to mail the eagle files around soon, but I'm so busy I can't guarantee I find the time before Sunday. Sorry!

  • 2*2 arc in a 64 style case would be quite neat I think...

  • Eagle format would be fab as that can more readily facilitate/change the size of the device a little... I can think of all sorts of different ways to present an arc as well as in grid form it could be mounted on all manner of shapes like a cube positioned such that it can be collaboratively interfered with or held in the hand like a Rubik's cube... Needs more thought but I sense massive fun could be had with changing the form factor and embedding it in other control surfaces...

    Yes the eagle software produces a BOM/parts list... It also massively simplifies drill hole issues when making gerber files for most normal pcb companies - even one offs (though this is mostly SMD which is something I prefer working with on account of generally making thinner profile boards)

  • I just sent you the eagle files. I hope that I didn't forget anyone... If you didn't get anything, please let me know!

  • Many thanks will have a long read and decide how to take this next project :)

  • @slowgrowth: wow! nice work reconstructing this. i imagine that was pretty educational?

    @tanais: we probably have some spare parts around if you're interested!

  • @tehn If you have any bits I would be interested as I have been doing rather well on the build recently. About to order the parts but the one thing I lack is, well, knobs and was about to machine some. Have some leftover Iroko that I am having machined to fit but if you have any bits sure let's talk.


    640 x 360 - 56K
  • @awaiting.deletion: please note that my clone most likely has the wrong sizes. I didn't have a real arc at hand so I simply guessed it until it looked right in the CAD model.

    Last weekend I finally managed to get my knobs done. They are milled from walnut wood. I can give you some hints if you have a lathe.

  • I think ally knobs for me. Though I might see about keeping the light shapers black.

  • Here we go.
    Progress. Slow progress. Made from the cutouts of my Iroko work table. Guy I know made me a couple and some square ones for when I play with the form factor.

    2688 x 1520 - 952K
    2688 x 1520 - 1M
    2272 x 1704 - 902K
  • I'm currently doing the soldering for @[awaiting.deletion]
    In the process, I noticed a really stupid error in the pcbs.
    Also I found that the setup process was a bit hard to understand if you're not into that kind of stuff so I wrote a little help file to guide you through it.

    All of that (including the eagle files) is now in my repository:

    And please: If you decide to build one, ask me for help and don't ask tehn or any other person involved at monome. I don't want my clone to be work and trouble for them.

  • Much gratefulness to Johannes,

    BTW I found some nice machined aluminium knobs
    Not the same as Monome's but nice and heavy.
    Yeah my hands are not up to SMD work.

    2448 x 3264 - 2M
  • Where did you find the knobs - they look wonderful?

  • Curious if anyone wants to go in on boards. I'd love to do an arc 4, by using OSHPARK means having 2 extra of everything. Guess I could make another arcclone2 but really just want one.

  • Also, a giant thanks for sharing this awesome project!

  • WHOOOOOAAA! I love the project.

    Side note: your eBay link is amazing. He sells some great looking kits for cheap. Interesting.

  • Wow, those knobs look really good! They seem to fit very nicely.
    There's not much gap between the knobs and the acrylic. Does it grind, when you push the button off-center? My encoders have a little wobble, hence the question.

  • if they do when the arcs return I shall just make the acrylic holes just that tiny bit bigger but not when I tested them out with the pots in place. We shall see. Worst case scenario is I make the rings slightly bigger and redraft the svgs to support it, but so far. No.

  • Incidentally I have two extra cases for this project. I had four made, just in case someone wanted to have a go. Thay are made from responsibly farmed Iroko offcuts from my mixing desk table and hand made by a local woodworker to a very high standard, they fit the PCBs perfectly and are designed for this project.

    I paid something in the region of £80 each. So that is what I am asking.

    1280 x 720 - 306K
    720 x 1280 - 214K
    1280 x 720 - 188K
  • still wondering if anyone would be interested in splitting/sharing an oshpark order for pcbs?

  • it really depends on cost shimoda!

  • before you start an order, let me please make some minor changes to the pcbs (component spacing, etc.)

  • definitely will wait.

  • @awaiting.deletion

    these look amazing

    Do you mind me asking where you get your PCB printed for these?


  • I'm also interested in the pcb/building an arc...

  • I went to OSHpark and 2 x 3 boards of each, conveniently makes two arcs with a leftover board and USB board for mess-ups/spares (or even a cute single encoder arc).

    This is BTW NOT a cheap way to make a Monome Arc but every time an Arc 4 came up for sale I was pipped at the post. In a scale of difficulty I would put this quite high because of the tolerances and the multiple source points plus the woodworker made several cases to make it worth his while. if you are monome, this scales, otherwise its a great insight into the precision of what Brian & Kelli does for a living.

    I use OSHpark for loads of small jobs now I am in DIY Eurorack land. They are slow at getting boards to the UK and I am sure there are faster services, but I like their simplicity. You do have surplus boards and that is no bad thing and it helps in group buys, but the BOM, the cases, time, the ponoko parts, the Front Panel Express top plates and knobs and so on all add up to more-expensive-than used.

  • @awaiting. deletion - thank's for the info.

    I'm considering internally splitting the 512 into 4 128's as using with the WW and MP more.

    Hence the boards printing query.

    Won't be modding the beautiful enclosure though :)

    I looked at OSHpark and the simplicity did attract me too.

    The arc is a bit above me though and the new mk kit is my current gear desire hehe