Reviving a destroyed Pint

  • @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. 😁

  • @Lia , what you are doing is amazing! Thanks for bringing us all along with your photos and careful documentation. {{Applause!!}}

    I do wish you could simply order replacement rails, etc.

  • @HorsePlay Love the name!
    Thanks for the compliments and taking an interest :)

    I'd love to be able to buy the spare parts direct from them. I'm at least thankful they do sell replacement parts for the bits that do get damaged with use like the bumpers, pads and fenders to name a few.

  • While waiting on some materials to properly build up a table suitable to rout my rails (tried a jig, was messy) I'm working on making my own footpads. First bit to do was the connector itself. It seems Amphenol LTW make these but from some back and forth on reddit is seems you can't buy them :(

    Thankfully it's not too hard to just make my own

    Fit is nice and snug with it able to lock in place like the stock one. Got some thin brass tubing coming next week so I can make the contacts inside.

  • Can't catch a break, seems these Pint parts are extremely hard to come by. Tried reaching out to some 3rd party repair but been ghosted so I can only assume they don't have any.

    The controller housing is bent beyond repair let alone the mounting fins completely torn off. With the little detail I can pull I'm currently just making my own. Unsure how watertight it'll be but I can find solutions.

    Currently on the 5th test model and managed to lock in the general shape, bolt spacing, light bar position, power button, cable coupling and motor/pad holes. Need to make a top half and put in some holes for the bolts.

    Contemplating if I should make my own top half. Would be easier in some ways and a nightmare in getting that curve between the front and back to line up. Transparent filament kinda sucks so might end up making it compatible and use my current lid.

    In regards to making it compatible with stock rails really depends on if I'm just that much of a CAD legend and guess it or if someone could swoop in and get me some crucial measurements since I have a hunch the spacing left and right isn't the same.

  • @Lia what filament you using? I would use either abs or petg and brush on some solvent then some plastic slurry. Would have to use mek for the petg tho.

    I've got a buddy that has one of those cheap $200 cnc contraptions and he used it to mill out a custom aluminum oil pan (i think?) for an old tractor. About the same size. It took a while tho. Those things are meant for wood art, jewelry and other really light duty stuff.

    I've used to bootleg a few Evinrude parts before. They were fairly small tho. Expensive but very effective.

  • @NotSure Curretly PLA, mostly for ease of prototyping and my printer isn't setup for any other filaments. I avoid ABS since it's not as dimensioanlly accurate as I would like without putting in the adjusted tolerances in my models. PETG might be a safe bet but will see how my PLA holds up since I get some pretty tough prints with it.

    Was in the process of making a CNC mill but it got stuck on the back burner due to other projects taking up time and money.

    Tempting to use those other services for alternative filaments. Definitely expensive though, I had a guy on Thingiverse tell me they wanted to print one of my modified OW stand designs and were quoted $700 through one of the printing services!

  • @Lia Yeah shapeways can be pricey. Aluminum SLM is pretty neat tho. Might wanna try uploading a model just to get a quote. I got a decent sized nylon part for $75 a few years back. Works well.

  • Had my sis ask me why I didn't just 3D scan the broken controller housing. 3 reasons that I'll share in case anyone else is curious.

    1. Most scanning apps either don't know how big the actual object is or isn't precise enough which will require extra fiddling in CAD after.
    2. Anyone that has ever tried modifying a 3D scan will tell you how painful it is. No flat surfaces or geometrically accurate angles make for a nightmare. Tried modifying a GoPro mount once that was 3D scanned and uploaded to Thingiverse. Spent hours just fixing errors.
    3. The housing is bent, so even if I pull the geometry I'd have to unbend it in CAD which isn't particularly easy as mentioned above.

    So I've been painstakingly making a variety of test prints along the way, slowly getting each new addition to the model dialled in. I'll of course be making some adjustments to make it more suitable for 3D printing and just a few extra bits for my own purposes.

    Anyone got any requests to add to the design?
    Tempted to make a version that will accept alternative power buttons since the existing one is simply a dome switch under a silicone cover.
    In case anyone wanted to know what the Pint button looked like taken apart.

  • Home stretch on the controller housing!

    All the internal components fit nice and snug. Even managed to get that pesky o-ring to fit.

    Stock top shell fits perfectly. Waiting on some bolts to come as I ran out of 25mm M4 bolts. Won't be using the stock bolts which to some might be a bonus.

    The mounting fins are guestimated as to their spacing but with all the info I've managed to pull I'd be shocked if I was maybe 1-2mm off width or lengthways.

    While designing I realised the stock lower shell has a thermal pad to help transfer heat from the ESC. So in order to at least try dissipate the heat I've built in spacing for a 50x25x5mm heat sink. Not sure if it will be enough but considering the shell acts as thermal mass rather than a heat sink then I might be safe...

    This is version 10 of the prototypes. V11 will be the final (assuming nothing else crops up down the line).

    Any additional things you'd think might be good to add?

  • @Lia outstanding work! Very impressive. Only thing i could even think of is maybe a 60V port for adding a vnr mod, and I honestly have no idea if that's even possible or effective. Maybe a USB charging port for a GPS tracker? Again, i have absolutely no idea if it's even possible. Just tossing stuff at the wall. Get that cnc up and running next! Just a billet and some reliable gcode away from ur own Etsy store lol. Great job so far.

  • @NotSure Not a bad idea, there is a 5v line which looks to be for the hall sensors in the hub and LEDs. Assuming it's not limited to a super low current I'd imagine I could piggy back off it and add a usb port. Worst case you install buck converter off the XT60 and step it down to 5v.

    For VnR I'm not sure there would be room to fit a port. FM did a good job squeezing in the connectors on there with little room for anything else. With some imagination I could maybe think of something.

    Next step is for sure the rails and then while I do that will attempt my own footpads.

  • @Lia what material have you printed with? Any concerns with temps on or around the heatsink?

  • @stinkyface PLA currently still, was considering PETG for the final one but will see if I can get away with PLA at a higher wall thickness and infill density. I'm not sure what sort of heat the ESC is going to put out yet but will be able to bench it once it's put together and let it run under load.

    Hopefully that puny 50x25mm heat sink is enough to pull whatever heat FM figured they needed to get rid of. Since the XR puts it's heat into a bit of sheet metal with no airflow I imagine it's not doing a whole lot and might be similar for the Pint.

  • @Lia
    Truly amazing work on this 3D build out. I will guess that others likely have some interest in what you have done with this.... Bravo. Looking forward to the final assembly.

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