Aurum Bro Build | Haero Deck | Molicel p42 12s8p | MBS Matrix 2 12s8p DS + 7inch lacroix tires
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Limiting RPM is easy in vesc tool. Say you have a 170kv motor and don’t want to spin it at more than 50V. ERPM = motor pole pairs * RPM = (motor poles / 2) * kv * voltage = 7 * 170 * 50 = 59500
So just set that in vesc tool for each ESC, and save:
As for voltage spikes, I don’t think motors experience that. And if you have a conservative setting like this, no voltage spike is going to kill your motor anyway.
And if your motors do die (which they eventually will regardless I think), wouldn’t it be great to already have your board set up for 16s so that you have more motor choices to choose from? 
Edit: It has been brought to my attention that limiting ERPM can limit brakes if you were to cross that limit. So limiting max duty cycle instead is the recommended approach.
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Lacroix wheels are 7.5 inches and just look at the clearance on that thing
And it’s already on the inner holes
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Yes. Though its not fair to see with that angle. With the other one, it aligns with the middle of the hub, so approx. 3.5 inch of clearance? My stock budget board with 90mm wheels had less clearance so if that was fine on my roads for clearance this should be too. It was also one of the flexiest decks ever with some bamboo.
Just because you can does not mean you should, if you ride exclusively on smooth flat ground then /maybe/ you’ll be fine, but the absolutely insane amount of stress from vibrations and the mass of a triple stack will absolutely destroy the mounting points on your enclosure. In addition the moment you shift your weight you will bend the enclosure and it will not take kindly to that, and if you go over anything you’ll shatter the ends of the enclosure
Like you do you, but when you fuck up you’re going to destroy your work, probably seriously hurt yourself, and give the entire hobby a bad rap
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I understand the risks. Thank you for your input.
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If there was a lot of experience with people running 16s on 12s motors, I would because you’ve given compelling reasons. I feel better if its hard-fixed to limit the voltage by the bms too. Yes they will all die eventually. I can’t tell you how much of a difference it will make because theres no data on that but I feel like it will with the experience I heard.
Watch the gifs. That is the stiff deck. You will see at least half of that flex just by going down a curb
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Gotcha, I just figured the love of the build might bring more like this.
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Maybe I could make boards for others but people already don’t trust what I am doing for enclosures. Hopefully it turns out well and I can do all the tests imaginable to show that it works flawlessly.
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Its cool to get advice, i know I’ve asked for a ton but in the end its your build, your way!
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I run a doublestack 32650 pack on Tb110s with absolute dog roads, you’ll be fine for clearance.
edit: just gotta watch for speedbumps.
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It’s not that we don’t trust you, but we, as a community, already tried and abused the living hell out of every single part we got our hands on for years.
It will look cool for sure, but everyone knows already exactly what will fail first and unfortunately it’s a critical issue. Abs is only used as a mould for the actual fibreglass shell, and even that remains questionable under 12s16p…
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Maybe the not the best choice of word but nonetheless I appreciate it and it will help me to design the enclosure.
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I think the best way is to print a negative mould and make the enclosure fibreglass.
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I’ll echo @ShutterShock by saying you don’t want each enclosure mounted to each other. Think about long-term ruggedness and failure modes. If one screw backs out, you could have a double failure on two of your enclosure segments. That a single point of failure with high consequences. Yes, it requires more holes in your deck, but that’s a better trade-off than having more weight loading up less anchor points. If you epoxy your threaded inserts in, there should be no appreciable change to the deck.
Additionally, if you go 3D printed, you need to reduce those sharp corner stress concentrations as much as possible. Add huge fillets everywhere, and ideally use a material with low stiffness / some flexibility like Nylon. PETG is a good budget choice if you can’t / don’t want to use Nylon.
i.e.:
If you’re really worried about flex, you can get creative with your mounting points - the closer they are together for each enclosure segment, the better (along the long axis of the board). You could actually place the mounting points inside the enclosure, but you’ll need an access hole through the outside, which you could seal later. You do not want any flex in your mounting tabs. Those need to hold strong. Design for flex elsewhere.
You should also figure out the resting curve of the deck, with you standing, and all equipment weight. Take a photo, load it into CAD, and design that curvature into the bottom of each enclosure. Better to have a small amount of tension and compression, than a large amount of tension only, pulling on your fasteners.
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Yes! I love those mounting points. I see your point and I agree with you and shutter. Ill go with more holes (16 in total) but m4 instead of m5 is okay? Do you have a 3df of those mounting flaps?
M4 should be fine. M5 are huge and probably overkill. I would use zinc plated steel alloy, with washers. Check the fasteners thread for threaded insert recommendations.
I designed those mounting tabs in 5 minutes in Fusion - nothing is to scale or size. Not to be rude, but it should be straightforward to add fillets to a basic design like this, especially if you intend to design full enclosures.
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I do basic fillets like following circles (rolling ball) but those are some unique curves. I need to look up how to do different types of fillets
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I highly recommend watching some youtube videos and doing some exercises before printing your designs. It will save you time. Also, there should be pretty much zero sharp corners in your design, so you should be using this button frequently.
My design was just the combination of 4-5 fillets. It’s nothing custom
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