Reviving a destroyed Pint

  • Hi all,

    Recently I've become the owner of a Pint that got snapped in half after a hit and run incident here in the UK. Here's some pics the rider took after the incident.
    The owner thankfully wasn't injured however due to legal complications with the OW being used here the police advised not to pursue a case; even though they managed to get the plate before they bailed. For those interested in pics and the post here are the links.
    Reddit post
    More images

    Unfortunately they had binned the destroyed parts and I was sent the wheel, controller and battery with the rail mounts for the axle. I was hoping to keep the rails as a memento to what the poor thing had gone through but I'll focus on bringing it back to working order before working on any tributes.

    Anyway, she arrived the other day and I've been cleaning the oil off her from the van. There is a lot of damage but electronically she looks fine having taken a closer look. Was a little concerned before purchasing and due to the distance between us and Covid it wouldn't have been sensible for me to see it in person. Risky but I trusted them that the info was accurate.

    Damage appears to be the battery communication connector had snapped it's clip off when the whole cable got yanked through the watertight sleeve. When the XT60 got tugged it yanked the power button connector apart and bent the leftover pins to the point they fell off after closer inspection.
    As usual the power button nut is loose and the plastic thread has snapped.
    When the xt60 reached the watertight sleeve it pulled out a thread one side causing the whole thing to become cross threaded making in difficult to undo without that large adjustable spanner. Being plastic it took a bit of careful jiggling before undoing it without demolishing the head.

    Battery appears to be fine though from what I can see. It's off so I assume when the cabled got yanked the battery went into auto shutdown some time after the accident.

    Unfortunately all of the mounting posts on the controller are completely destroyed and missing so even with new rails she won't connect to anything. One corner on the controller housing has snapped off also exposing the gasket.
    On further inspection the lower metal housing on the controller is bent opening up the seal where the LED's are exposing the gasket and an opening.

    The hub also sustained a scrape but for the most part it looks like the hub's structural integrity has been retained. Pressure is still present so we should be good, just needs a bit of paint.

    After all that though, I can confirm when bypassing the busted power switch I can turn her on and off. No errors upon turning on and connecting to the app, motor maintains holding torque too once connected. Both front and rear LEDs glow and I would imagine if I short both left and right pad sensor pins to ground I could get her to spin up. Voltage entering the controller was 60v so looks like this little Pint wasn't far from home when things took a turn for the worst.

    So my question now is.... where can I buy some rails, bolts and maybe even the lower controller housing? Being in the UK shipping might be an issue and I'm not looking to break the bank this early after Christmas D:
    I'm willing to just DIY it and and give this pint a new life as something a little different but that kind of feels wrong.

    I'll keep you all posted on this Pint's recovery. Any suggestions on part availability or if anyone is parting a board out give me a poke.

  • I would look into using JBWeld to re-make the controller housing box. I would think about putting in new threaded inserts in there before you start, so the screws can grip nicely. An alternative would be to put the screws in there before you JBWeld, then take them out before it sets. But, I would think my first approach better.

    Since everything might not fit perfectly snug, I would suggest keeping the gasket, but also using 100% pure silicone around the controller box when you reseal it.

    As for the missing parts, there are a number of people who part out boards on Reddit and FB, try posting there.

  • Intensive caring @Lia, my take is put the controller above the wheel on a box fender after you find some rails, and build a platform for your front footpad. Not as pretty as some solutions, though effective.

  • @Lia lots of ideas on the twowheel thread! You have half the parts already...

  • @biell Sounds like some solid advice. Not on FB but will hit up a few places and see what's available once things have settled down a bit.

    @blkwalnutgrwr Could work, would need to make sure it's perfectly parallel with the boards level so it doesn't think it's too tail or nose heavy at any given time. Will try repair the casing's integrity first though then look at alternative solutions. The area's that are vulnerable don't appear that bad but the dunk test will answer that once I've tried sealing it.

    @stinkyface It is tempting indeed. I'll certainly try putting the motor on something else for sure just to see what it's like.
    Had this planned out in CAD for another project I think I hinted at in that thread.
    Have yet to actually begin fabrication as it's still just 3d printed test pieces. Shouldn't be hard to try putting the Pint motor on the back and ditch the suspension. Could probably even remove the front steering and rely on the pint tyre to keep the board stable instead.

    Many thanks for all the input so far :)

  • Been scouring the web for some rails for a bit and have yet to get a nibble on some rails. Seeing as the longer a project sits the more likely it is to remain that way (past experience lol) I'm going with the option of temporarily modelling the rails so I can at least get it all in one piece to test on the bench without resorting to clamping the hub axle to my bench.

    Looking for some accurate dimensions so I can CAD something up and print off. Thoughts?
    Pint rail dimensions

  • With limited measurements I've started to take what I've got from my own calipers and one redditor that managed to get some. Didn't realise how odd the pint rails were. Must be a pain to mill!
    Haven't modelled the curve on the exterior yet, figured I'd leave that till last since it's purely decorative.

    Managed to get the fit right first time but haven't knocked out the bolt holes yet. Really this is me just faffing about till I get rails but figured knowing the exact dimensions might be useful if not for me but others once I've got them 100% sussed.

    Biggest issue is currently is Imperial vs Metric. I'm a metric person but if FM designed this around Imperial then the nice metric numbers I'm guesstimating might not match what would be a nice imperial number that they may use. In other words whilst I might use a thickness of 3mm they might use 1/8" which would be 3.5mm.

  • @Lia take more measurements imo. The answer will probably reside in the data. I'm guessing that it's much less likely to be mixed units on individual parts. Outside of 3dp and barometry, I only use metric when necessary.

  • "I love it when a Pint comes together"

    Lots of trial and error, only have 4 bolt holes to put on the front end of the rails and I'll have a fully CAD'd model of the Onewheel Pint rails. Tolerances are pretty good so far but will get them tighter once I actually have some real rails to compare too.

    Last 4 bolt holes are the ones for the controller. Technically I only need 2 from one side to do the others but I have neither since... all 4 are missing so it's not easy to guess and confirm I'm right.

    Nonetheless.... nearly done so I can test her working in one piece. The temptation to stand on it is quite high... bad idea.... it's 3D printed PLA.

  • @Lia if you are thinking about getting some rails milled, you could design in the rear to increase the concave effect, and the front as well now I think about it.

    More or less length given you know your stance?

  • @stinkyface I was tempted too, don't own my own mill so the cost of getting someone else to make these would be nuts. I am slowly constructing a CNC router though so some time down the line I could.

    That said I'll be releasing the files so anyone that wants to do it can. Would be cool if we can get some custom rails for the Pint much like the XR has custom rails.

  • Starting to look like a Onewheel again.

    Decided to have a swing at getting the board to spin the motor up but need to engage the footpads. Since I don't have any and don't really want to buy pads right now I assumed I could use the same shorting technique I've used on my XR. Alas, I don't have a pinout.
    After doing a bit of measuring I've found ground and 3.3v but cannot confirm what the other 3 are.

    I assume lower left and lower right are pad left and pad right with centre being the led data pin... but connecting the other 3 to ground doesn't actually trigger the app to say a pad is engaged. It's possible the pads actually engage when connected to 3.3v but I don't fancy sending voltage to something unknown unless anyone can confirm my suspicions.

  • Nobody able to tell me what the pinout is for the Pint...

    Figured out what pins trigger the Pint's footpad and decided to take a swing at the motor too. In turning it on to test the motor spins I.... forgot my rails were PLA and that the Onewheel doesn't just... gently rotate. Nope it torques it's way into oblivion, not only snapping all 4 rail sections but in doing so ripping the connector out BMS side. OOPS!

    Anyway... this looks to be correct from what I'm able to measure and trace. Please note the lettering is for this reference and doesn't reflect any component identifying scheme FM use.
    Onewheel Pint Motor and Footpad Pinout.jpg
    No idea what J is for. It's sitting at 3.3v when the board is on much like Pad L(L) and Pad R(K). Oddly enough you can connect Pads L(L) and R(K) to either pin I or ground and they trigger the board.

    If anyone finds out more on this or has a better explanation I'd love to hear. Will update my graphic if I get more data.

  • @Lia You illustrate a degree of patience and attentiveness I can only muster in very short sprints and even then, only if motivated by significant personal gain. It's very impressive.

  • @NotSure Thanks :) I like to tinker, that and getting the pinout should save me money if I can make my own footpad.

    3D model already exists which is what I was using as a placeholder so if I can get a decent set of force sensing pads I’ll be laughing.

  • Can't get ahold of any rails through the usual channels, making my own.

    Since I've made replica rails in CAD and 3D printed to verify my measurements the next step would be to just make my own.

    Milling is tedious and expensive so I've dismissed that idea. Pre-made box section exists though and after a bit of looking I found some that's almost ideal for making rails from.
    ALUMINIUM CHANNEL U - SKU: length: 600mm, size: 1.1/2 x 3/4 x 1/8 (38.1mm x 19mm x 3.2mm)

    The rails need an inner spacing of 32.5mm from what I've found with these come to 31.8mm. All I have to do is rout out 0.35mm either side and they'll slot on. Then I can trim the depth of the U bracket down to spec. After I'll drill out the holes, countersinking a few, tapping others and then cutting the ends at the appropriate angle to meet flush with the bumpers.

    Easier said than done?

    I don't have any bits capable of chewing through aluminium with a flat tip so waiting on those to show up. Then I can make a jig to slide the rails into the router to shave off enough material on the inside of the U profile, the rest will be a cakewalk. I'll keep you all posted!

  • @Lia cool! Make sure that jig is sturdy! May wish to consider using incremental jigs if the material proves particularly difficult to rout considering the tight tolerances.

  • @NotSure Good idea, if I'm not careful I might send the extrusion into the wall if I go too deep. Will consider doing minor cuts :)

  • @Lia Lol! Literally my exact concern. Good luck!

  • @Lia this is fun. 😁

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