Open Source Precision Trucks - Looking for design feedback

Hey guys,

Largely our community uses stock trucks and then modify to accommodate power. Lets think from the ground up. What do WE need.

My Background: I have a machine shop and plan to machine these trucks and do the CAD/CAM in our fab shop.

My main motivation is to solve and make more elegant, the motor mounting, drive wheel side accommodations (if necessary) and what ever.

What features do you wish you had on your trucks. Here are some ideas and questions I have.

  • All aluminum machined parts
  • Hardened/Tempered Steel axle inserts
  • Spherical Bearing Pivot
  • Integrated motor mount for Single/Dual/Inside/Outside
  • Clean Design
  • Designed in Fusion360 - Open Source

Feedback from you guys please:

  • on the above items (of course)
  • Preferred Geometry - widths, heights, baseplate angles
  • hub motor integration?
  • Maybe some kind of heat sink functionality on the motormount/truck combination. Thick aluminum motor mounts already do a good job at this, but could be exploited more by adding surface area with fins, which would look killer too.

  • Wider trucks that accommodate 2x xx64 or even 2x xx74.

  • Getting high speed stability without huge turning radius

  • Integrated suspension

Good luck!


I believe the best hanger shape for a truck would be a square, basically the caliber hanger without the curved part. I’d love to help a bit with the design if needed, I’m a basic user of OnShape and F360. But I guess there are more advanced people here so only if you need someone.

So the features:

Vibration dampening somehow (maybe a special riser?)

Integrated suspension as said above

A mount that comes with the truck (maybe same principle as the Enertion mount?)


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Changeable axles so that you can use different lengths - the Trampa hubs for example are 34mm instead of the 24mm a normal wheel has.

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220mm+ hangar


Definitely a wider hanger, that allows dual xx74 motors, especially for esk8s which could be used off road or for semi-off road purposes.

Caliber profile - only because mounts are widely available. However as long as the design of the mount for the trucks was good enough, I have no preference to profile of the hanger. The motor mount should also be able to secured at multiple angles around the truck to suit user preferences.

Suspension would be nice (as per Seismic G5), but not deal breaker, especially if you’re using pneumatic tyres.

Adjustable baseplate angle - because why not!

Just thinking out loud here:

  • Changeable axles might be possible, by using a channel milled along the centre of the hanger, which is secured by a pair of locking nuts, like nylock nuts, which are partially recessed into each end of the hanger.

  • Also, the extendable axle inserts could be reinforced by the longer axle, securing it in the same way as described above.

  • If you wanted to get all experimental, a flat surface around the kingpin to mount wider and or thicker urethane bushings (not saying I have tried this, or if you could even source these bushings). It might be interesting to consider, at least from a design perspective if bigger urethane bushings might be helpful in addressing speed wobble.

Not sure if these ideas meet the requirement of whats in a precision truck, but I think they would be cool.


That would mondo mega badass awesome. Most of my maintenance time is spend getting the motor mount clamp straight. It just tends to move a little bit every 50-100 km. A decent set of trucks with a solid/welded clamp so you jus screw the motor mount plate down at whatever rise you want would be great!.


mainstreet, RKP is not the way to go they are unstable just like regular TKP.

We need something different than skate world, it doesn’t work.

Where are you located ? I can show you some innovative longboard gear that could change eskate

Just an insight, I have made the word’s first entirely 3d printed skateboard trucks, and ride it everyday for the past 6 months without issues, I will give the design out someday

pics or it didnt happen :slight_smile:


No-one mentioned thicker axles/hangers.

Riding eboards with such powerful motors and batteries i feel the calibers are from the past. We need something really up to the task, i think more and more about the ronis. i would love to have a truck which can hold the turbulences of high speed and agility at lower speeds. Namely ronis btw, with the shape of the hanger like calibers to be compatible with all the mounts already in the market.

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I Hopefully will have my truck hanger done by next month. Caliber profile (205mm width), allows dual 6364 motors to be used with 60mm axle bolt and dual 6374 motors with 70mm axle bolt and spacers. I made them fit on caliber base plates and they use axle bolts like on Surf rod trucks. Once I finally get them done, and know they work, I will be sure to share my model with anyone who is interested.

3D printed



Looks great!

Hahahah we are rough bunch lol


I drew these up a couple weeks ago, no machine shop yet. they won’t be cheap.

250mm hanger. hex for mounting. rounded end for pulley bearings. ronin style dual pivot because why not!


OK guys, great feedback.

Here are some of the goals/issues:


  • The design will be able to be machined on a 3 axis milling machine with minimum setups and simple work holding and fixturing. This will keep costs reasonable. For instance this would make square profiles simpler vs round or hex like @saul added (real perdy though Saul). I want to make it relatively easy for a basic CNC shop to execute. Maybe even on a CNC router.

  • Patent infringement is a risk. For instance, Ronin’s pivot pin was patented quite recently.

  • Longer hangers to accommodate larger motors. In fact it would be super easy to change the hanger width in CAD or even offset a side for a wheel gear with in integrated bearing.

Exploring - thoughts guys?

  • I like the idea of a spring return with no bushings; like the Seismic G5. My understanding is that their patent expired in 2013. The intent will be to improve this approach and not rip off the design :slight_smile: We will try to use commonly available die springs.

  • I am exploring using a solid axle or axle inserts

  • 3 part baseplate? Like this? [from here].( This design and ones like it (its not the only one) allow for pretty simple milling yet a nice feature with the adjustable angle.


I only have a few requirements.

  1. 215mm wide hanger or more.
  2. Not too expensive
  3. Stable at 45kph/28mph but still able to make sharp turns.

I really like the idea of adjustable angle if does not add a huge amount of cost. But if its a fixed angle I would want 50 deg.

If I didnt have a budget I would say integrated motor mount and heat sink fins but that seems like it could add a lot of machining time.

@saul’s design is super cool

Thanks. I know the patent could be an issue, I was planning to contact Ronin about this since they’re local.

And I was thinking to keep cost down it could just be a custom hanger compatible with the cast Ronin baseplates. This means you could upgrade to the CNC baseplates for adjustable angles.

The regular base plates and pivot ball is about $30 each. Vs the CNC hangers like $300+

As for the hangar shape, square would probably be the easiest, but hex is just a large chamfer on that. And gives more surface area for the clamps.

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Been geeking out on CNC trucks for almost a decade now… Here are my thoughts

  • RKP design with a standard geometry. You can really cut costs for the end-user if your CNC hangar fits on a cast baseplate. Randal has 50, 42, and 35 deg plates for cheap. Sell it as full CNC hangar/BP or CNC hangar only.

  • Motor mount. If you’re making a truck specifically for e-skate, an integrated motor mount would be ideal. Gets rid of the clamp entirely. If you made a hangar that supported two motors, you could create a strong yet lightweight design by creating a torsional box

  • Directional setup. Use a higher angled baseplate front (45-50°), and lower in the back (20-35°). Then the rear tracks the front, resulting in a more stable setup. Adjustable baseplates would take care of this. Maybe just focus on a rear low-angle truck at first

  • Inline axles increase grip (axle is inline with kingpin, not offset like a Randal or Caliber)

  • Screw-in axles get you a range of widths with a single hangar. Many CNC trucks on the market use this same approach to great success

  • Avoid spherical bearings. They get twitchy at speed. A ball pivot with high quality urethane pivot cups feels much better in my opinion. At the hangar/kingping interface, I prefer a urethane plug (like Rogues) to a spherical bearing.

  • Springs are gimmicky. Seismics were always a pain to setup and never felt right to me. Urethane bushings are much more readily available for any duro you’d want

  • Adjustable pivots. If you make the length of the pivot adjusable, you can make the hangar fit on (almost) any baseplate {see Zealous trucks for inspiration, but probably not necessary}