Surf Rodz Axles with integrated mounting plate

So, you may have seen this link earlier.

Early in September I was having a discussion that sparked an idea which led to this:

A semi-permanent axle for Surf Rodz that is compatible with the @LR-designs and @moon mounting pattern (46mm diameter)

I had a pair of prototypes produced.

Looking back, I should have had 4 or 5 sets made.

I tried a few setups out (haggies, 107’s/BKB, Popocas/BKB) and the axle was a consistent 10mm long.



Not the end of the world - it’s a prototype. The final axle will be 10mm shorter.

This is a SR TKP 127mm hanger with the axles and an additional 5mm spacer.

Dual 6355

Dual 6374

To be fair, the dual 6374 needs an extra 1mm shim between the axle and hanger to get some clearance. The axles can accommodate this extra spacing. I haven’t tested it yet, but I may be able to go past 6mm of spacing on the inner axle.

Here is where the grub screw caught the flat at 5mm spacing.

There’s another mm there at least, and we can remove another 1.5 - 2.0mm

Here’s a pic of the axle threaded completely into the hanger.

So where are we now?

@mmaner is testing the axles out now.

He rode them and experienced some loosening on one of the axles. He’s applied loctite and is feeling confident about the axle not moving.

Once I get some feedback from Mike and others the design will be finalized and sent to fab. The current iteration of the design looks like this:

Hanger axle on the left, matched front axles on the right.

I know - these are 10mm across the entire length of the axle. If there is enough preference a stepped axle version could be made. Something like this for 608’s.

22mm of axle with 13mm of thread.


Thanks for reading this far!

If you have any constructive criticism I’d like to hear it. This is an alpha design. Once we get some real-world feedback we’ll proceed to the beta.

/edit The black TKP hanger pictured above is 127mm, not 149mm.

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This is so Innovative, doesn’t this make the length of the truck like 300mm though?

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The mayor strikes again!!

Awesome idea man!! I would definitely grab a set of these when they are available

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Brilliant idea incorporating the mount into the axle. I want 2 of 'em now lol.

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Excellent Matt, as always!

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This is good

My pattern is still 46mm :hugs:

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This has got to be esk8 invention of the year! This idea, if it works in practice, would allow people to use any truck (with removable axles) with any drive chain :open_mouth:

The one thing I’m scared of is this being a somewhat permanent solution. If with a wrench and a sudden rotational impact the axle can come loose (think, secured with blue loctite), then I think a sudden bump while riding or impact could do the same. Or, if you use red loctite, then removing the axles for different ones requires heating them up.

Then again, can’t imagine most people often changing from 1 axle size to another, so let it be permanent :slight_smile: So fucking cool!

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A good wrench with a strong arm, green loctite on the grub and blue on axle…it ain’t coming loose.

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Just an idea: if you use mounts that have cross bars, these bars will eliminate loose axles because they prevent the axle from turning ( each axle is tightened on opposite direction to each other). Am I onto something?

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For that extra security, yeah, but I put loctite on the grub and axle last night, and jumped up and down on it today. I promise you it won’t move.

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So the axle mount adds 168mm to the hanger width.

A 200mm RKP would bet 368mm thread-to-thread with 212mm of space available for motors.

These would allow for smaller hangers to be used.

150mm RKP could accommodate dual 6374.

Gotta run out for a minute.

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Jesus Christ this is beautiful. I made my own and they were ugly AF.

Edit: want want want.

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And guess what uses 10mm axles… Kaly wheels. Mmmm hmmm.

Great work Matt!

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Dude… this is so rad. Why you no tell me about this sooner :star_struck:
Do you think dual 6355 would fit on the 127 tkp hanger with these?

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Nvm lol. I know they will.

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This is a great idea!!! Neeeed this

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I have a feeling that your prototype axles that are slightly too long might be perfect for venom magnum wheels @akhlut

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So, yes. Example! I’m running haggys on 177TKP with 90mm axles. My OAL is ~ 320mm. With this setup the OAL goes up by 25mm to 345mm. So not a huge difference in width.

What these do is expand the solution set for hangers + motors.

If you stick with the original hanger the OAL will be wider by a minimum of 12mm. What you gain is space for motors.

If you’re going to use smaller motors your hanger requirements go way down. Like @Skunk asked about 127mm hangers. With 6mm of spacers between the hanger and the mounts gives you 151mm for motors - big enough for dual 74’s. That’s actually what’s on my daughters’ board above (I had to go measure to make sure - will edit OP).

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I have concerns about loosening as well.

Loctite is a solution, but I’d really like to have a purely mechanical solution as well.

The prototype has six faces for the grubscrew to grab, I feel like this is too many. I’ve gone and reduced the number of faces to five.

Two reasons for this.

First, if the grub slips even slightly the axle can begin to rotate out. If there are fewer faces the axle cannot rotate as much with the same amount of grub screw slip.

Second, the threads that engage the hanger are M8x1.25 For every 1/5 rotation the axle will back off the hanger by 0.25mm (1.25/5=0.25) So if we have to back the axle off the hanger by a maximum of 0.25mm to make sure the grub screw engages a flat instead of corner I’m willing to take that trade.

When the TKP hanger and the engagement surface are parallel the distance between the planes is 5.536mm. An M5x6 screw should almost touch the hanger when properly aligned. Loctiting this screw should lock the axle into place.

I’m not married to this pattern though. A more constraining one looks good as well.

I need to do the math on this a little more to optimize the grub screw length. Thanks for making me think about this some more!

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Yes, crossbars should help so long as they are stiff enough. I’m thinking that the ideal pattern here would be a triangle - one crossbar between the motors and hanger and two outside the motors forming an isosceles triangle. That should reduce or prevent the torque you’re describing.

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