Taper-lock motor mounts for MBS Matrix 3

After 5 years of designing motor mounts I’ve boiled it down to perhaps the simplest and most effective design possible for a fixed angle motor mount.

Our newest Matrix 3 mounts utilise a single insert taper-lock system thats built upon our pro motor mount design that debuted the concept (pictured below) and proved its effectiveness.

We combined this system with the DNA from the beefier and lighter single piece motor mounts on the Radium board, reducing the number of parts from 8 down to just 2 for these new mounts.

This new system features an insert wedge with tapered walls that slide against equally tapered walls on the motor mount. A single bolt tightens the wedge into the tapered seat, causing it to slide inwards toward the truck hangar. This exerts pressure on the hangar over a large surface area, which prevents things from coming loose over time after aluminium compresses as is the case with grub screw clamps.

This system also locks to the hangar from all 4 sides, unlike mounts that bolt to the screw thread thats present in matrix trucks, which pulls the mount into the hangar causing contact on only 2 faces.

The taper-lock system also gives the bolt a mechanical advantage to push the wedge into the hangar, meaning most of the force thats pushing back is pressing sideways into the bolt instead of along its length, reducing the chance of loosening under cyclic vibration. But to be certain, we use both a spring washer and nyloc nut. This ensures the mounts can not come loose, even with no Loctite.

Reducing the number of parts, complexity and reliance on expensive 7075 alloy has also allowed us to reduce the cost of these mounts by about 50% compared to the pro mounts that came before it, which is a cost saving that we pass onto you guys.

Another huge thing about these mounts is the time to install them. With only 1 bolt and no Loctite, it literally takes 30 seconds to install each mount onto the truck permanently, which is something I really wanted to achieve after realising how much time on a custom build is spent just installing mounts.





These also have 4x M6 idler mounting holes so you can get the best tension for different pulley setups as I found idlers to often be either too close to the wheel pulley or not provide enough tension on previous designs.

In addition there are 2x M4 accessory holes that can be used for mounting stuff like 3D printed board stand guards or a motor cage if there is enough demand for those.

So yeah thats basically it. There’s more info in regards to specs on the website. And the price is currently $168AUD / 113USD for two mounts. For vendors we can do a better price. These mounts and trucks should be a great low-cost setup for a production board.

Happy to answer any and all questions and can’t wait to see what you guys build! :call_me_hand:

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@Tony_Stark these look incredible! Amazing work!

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Hawt

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Very cool stuff guys, nice design!

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Man once again ingenious
ClappingLeonardoDicaprioGIF

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Agree with all above!

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Is there a reason for this hole?
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Or I guess maybe a better question is if there is a reason for these little hangover pieces other than design/aesthetics?

Not trying to bash them at all. I’m just curious.

I know they were made for the matrix 3 trucks, but any idea if these would fit with the shape used by the board dynamics hangers? Even if they require some user end modifications to make it work I might still be interested. :thinking: Assuming that the angle they’d up at was usable with RKP trucks of course. I just really like the idea of being able to move the motors around or off without removing the motor pulley from it for faster swaps. It is a pain in the ass to get my motor pulleys off because they’re such a tight fit.

really mate how long u been on here and u don’t know how to spell boardnamics /nooooooob

And no, they would not fit BN trucks haha

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so many mount options for BN hangers, we dont really need more. I have a feeling they just wouldnt sell. For the general purposes of the BN trucks, BN motor mounts are sufficient

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Thanks everyone!

Room for motor cables and weight reduction.

Also weight reduction/aesthetics. These mounts are 16mm thick and pocketed out to achieve a lighter more rigid structure than if they were thin.

The wedge only has a small amount of travel before the bolt hole restricts it, so at the moment I am not even sure if they will fit a 20 x 20mm hangar (Matrix 3 are 22.5 x 22.5). In theory they should so I’d love someone to test it. But they won’t fit anything smaller for sure (I think boardnamics are 18mm in smallest dimension from memory and not equal distances).

We can however make a bigger / different shaped wedge to fit some other trucks. The main limiting factor is the corner radius on the motor mount side which theoretically could fit a hangar with 1.5mm radius but in practice it most likely wouldn’t sit flat unless the hangar had at least a 2mm radius.

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I don’t have calipers but I believe you are right. looks to be 20mm x 18mm Where the height is 20 mm when looking at it in a t position (no idea of a better way to explain it).

I have found that adding a layer of epoxy on the inside of a motor mount clamp works well to help make up for any issues in size although I did that for a mount that was used and was worn unevenly. Before adding a mixture of epoxy and aluminum dust, it would fit on and tighten but would wobble a tiny bit in a certain direction.

However, I don’t see why the same method couldn’t work on a mount that was just a bit too big overall. It just might involve some more careful sanding by hand to make sure the wedge piece would still properly slide in. The top not being square on them could also cause issues/ limit the position options on the hanger too due to the wedge shape. (I don’t think adding epoxy on that piece to change its size would be a good idea)

I doubt anyone else would bother with or want to have to change the shape, and I’m not 100% sure the epoxy wouldn’t wear down with time. If you do make a wedge that could make it work then I’d at least be willing to try it.

I was also thinking that it may be possible to just use a separate hanger clamp and then just drill and tap holes in these motor mounts but that sound more annoying to do tbh.

I just like the look and features of these ones. :person_shrugging:

I did not realize that he decided to improperly spell a word for no good reason in his brand name.

It’s a brand name… it doesn’t need to be spelled like anything

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It’s not misspelled if that’s the company name

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