MTB build suggestions, new here

DIY Builds
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Hello, this is my first post, but I’ve been browsing around quite a bit.

I’m 34, grew up skating (flat ground, rails, stairs) and snowboarding. I’m comfortable on a board, but it’s been a while.

I’ve been researching prebuilt boards, but for what I am looking for, I really feel like I can build one myself, and in turn also be able to repair it. I’m an engineer, I should be able to do it myself, right?

That said…I have a basic understanding of eboards, but I don’t fully understand how the whole system operates. Are there any schematics out there that show a general layout of all components on the electrical side? For example, shows the battery, shows the ESC’s, motors, all in one? I don’t know what an esc truly does, I don’t know where the remote signal goes to in order to transmit power to the wheels.

Next, I’m looking to start collecting parts. A couple things to note: I prefer quality and component durability over performance. I prefer range over weight savings. I need to be able to go down trails with gravel, small sticks (think metro park trails), as well as some on road riding. I’m a big dude as well, about 250 lbs (working hard on it). Speed goals are I think reasonable, I would like to reach 30mph and retain as much torque as possible due to my massive gut weight. My budget, is open within reason. I would like to build something that will last. Also, I have a decent 3D printer, solidworks, and access to fabrication equipment (press brakes, cnc mills, lasers) and don’t mind making some of my own parts.

Can someone help suggest a build, or point me in the direction of a similar build? As for batteries, and box…I plan to fabricate my own box, but would like to figure out an ideal battery configuration first. I want all the range I can fit basically, while still being able to fit my feet on the board comfortably. Top mount is the plan. A couple of the things I do think I’m decided on would be straight gear drive, 2wd with ability to be 4wd in the future, and matrix 3 trucks.

Hopefully this isn’t too crazy of an ask for a first post! I’m mainly looking for build suggestions, and realistic guesses on range.

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If you’re hell bent on building a board, awesome and go for it. This is the right place.

If you are open to buying a diy board, there are some good ones for sale here.

The cost will add up and you will likely make a mistake where something isn’t compatible and prebuilts have come a long way. MBS’s new Agent series are awesome, as one example.

Real quick top down view of how everything works while in school pick up line:

You create the “load” on the board (how much energy it takes to move you how fast you want to go). This input starts from your remote and goes to a receiver plugged into your ESC (electronic speed controller). It’s just like a big RC car. The esc takes this signal and relays the command to your motors to start spinning to meet that load. Your motors are dumb and will just take whatever commands they are told by the esc. Meanwhile, your battery has to be providing the power to this esc. Think of the esc as a big power/signal converter. Battery voltage and amps get converted to usable signal via the esc and your motors say “Okey dokey”.

If your load is too much for the esc/battery/motors for some reason (you’re the size of @xsynatic, you’re climbing a hill with @BillGordon’s mom on the back, etc) several things can happen. 1) your esc shits the bed and let’s out the magic smoke 2) your battery just drains too quickly 3) your motors can’t provide any more power and you stop 4) something else bad that randomly happens

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First, thanks for the weight reference with someone’s mom on my back. That really helps put things into perspective :grin:

I really do want to build. I think it will be a good challenge for me. I love designing stuff, and having a deep understanding of my board will possibly inspire me to make custom parts for it in the future where the market lacks.

Actually your space invader build in a nut shell is what I’m going for, but I’m good with a trampa or MBS deck. I’d like to figure out how to route the wires under my feet but in the same space as the deck.

My first purchase actually will be the deck and trucks. From there i will have something physical to measure and go off of.

Motors and drives will be after that, then esc to match. This is where I need the most help, I think, considering my weight and my long range goals (and deciding what would be realistic). Also considering quality and durability over performance.

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Reacher motors are hot right now

Makerx escs have been pretty good (I forget which version has been most reliable)

MBS is rumored to be selling their super sexy top mount enclosures separately soon… I think you may be able to work out a good configuration with Joel to get the trucks, deck with integrated channel, and whatever other bits you’d need to get rolling. If you’re not making the battery, this would be my option. Up to you if you want to go vesc or something more locked down.

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Good call! Building these is a lot of fun and super addictive. Glad to see another person getting into EMTB. The search function here can probably teach you everything you need to know but people are very helpful in the beginner question thread too. Excited to see what you come up with.

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Honestly, the first thing you should do is figure out what you want to do about the battery, IMO. Building one yourself from cells requires quite a few things like a spot welder, fishpaper, nickel strips, fishpaper rings, and probably some other stuff I’m forgetting. There are cheap options for spotwelders, and I’ve gotten away with that route, but a good one is pretty expensive, especially if you don’t have a car battery sitting around and don’t want to pull one from your car for the project.

Buying a battery built by someone else is quite expensive unless you find someone selling something used here.

Lipos are also an option if you want to do something DIY without building a battery from cells, but I don’t think they’re the best for range. I haven’t messed with them at all, though.

It sounds like you want to do a custom battery box, and if that is the case, those are probably your options.

As far as how the electronics are laid out: Beautiful diagrams! NO WORDS (SERIOUS) - #6 by Excess
has a bunch of stuff, but
image
is a good example IMO. That assumes you’re using a loop key, but there are options for ESCs with on/off features or anti-spark switches that don’t use loop keys.

Edit: Actually, I just realized that diagram would require the loop key for charging, which I don’t like, so I’d move it after the split in the charge port. It’s still an alright example, though.

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Curious, has anyone built one with a tig welder?

Thanks for sharing the diagram. What is a loop key?

I’m not dead set on building the battery myself, but it would be great experience. I was thinking of a large box with large chamfers on the top for extra shin/leg clearance. Maybe a trapezoid shape.

Good call, I will brainstorm/research a battery config and maybe share it here if someone wants to check, that would be cool.

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Thank you. I will look those up. If I understand correctly, VESC is more capable than regular ESC’s? What do you mean by “something more locked down”? Like something more tried and true?

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You can’t build a battery with a standard welder. It would heat things up far too much. You aren’t even supposed to solder them because it gets them too hot. The only correct way to build packs, AFAIK, is spot welding the cells to nickel or copper strips. You can solder wires to the strips, which you ideally want to do before welding, or at least tin the strips before welding so you’re not putting as much heat into the cells, and then spot weld the strips to the cells. There are a lot of examples in https://forum.esk8.news/t/the-battery-builders-club/

A loop key is a connector that is used to break the circuit to turn things off. You use an XT90-S, which is a connector that has a resistor that makes contact first to allow capacitors to charge up without arcing before the connector is fully inserted. There are also electrical anti-spark switches, but because skateboards use high current, they cost a bit, and they are also another thing that can fail. Some ESCs also have integrated power switches, in which case you don’t necessarily need to have a loop key or a separate anti-spark switch.

The battery is arguably the most important, and usually the most expensive part of a build, especially if you want a lot of range. It’s usually good to figure out what you want to do for the battery first and then go from there. If you build your own battery, that will be by far the most difficult and time-consuming part of building a DIY skateboard. If you’re going to use something premade, there are battery builders on here, or more commercial options like just buying the MBS Agent pack.

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I would not recommend building your first battery for your DIY. Maybe try building one for a power bank or something similar.

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An intro on esk8 batteries and notations:

VESC is a Variable (changeable) ESC. Instead of your esc being a mysterious black box that makes your motors turn, you can connect to a vesc with your phone or pc and tweak all sorts of values. Throttle curve, motor amps, brake levels and curves, etc to really let you dial in your own settings to your liking. The downside is that 90% of the vesc settings aren’t meant to be messed with, so you can easily fuck things up when programming it. Lots of tutorials here on how to set them up. You shouldn’t have a problem with a decent engineering background but everyone makes mistakes.

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You give vesc too much credit.

There are a myriad of downsides to vesc. Vesc will become the bane of your life. You will love it, hate it, swear the most vile profanities you’ve ever sworn at it.

But it’s somewhat of a necessary evil as a configurable motor controller because there really aren’t any other options out there.

That said, there is plenty of inspiration to be found on these forums, don’t be shy about using the search button and dragging up old build threads!

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I learned the hard way not to keep updating to new versions and fucking with stuff :joy:

Once I got it happy, I stopped poking the bear.

(dude should just build an agent disassembled)

Maybe mbs should sell a diy kit for people who want to learn how to build and save a few bucks.

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If you’ve got access to a CNC machine and are a competent ME I would consider the possibility of building a suspension board. The biggest problem I’ve had with my truck-based mountainboard is doubletrack with big gravel - it just beats the crap out of me.

I had plans to build my own full suspension board but then I ended up with a Propel Endeavor and while it needs some TLC it’s already better (though not great).

In your case it might be good to have a 2-phase project, the first one just regular MTB trucks and a basic deck to prove out the drive, battery and electronics, then Phase II.

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If there were an option to buy the Agent without the ESC box, I think that would be an easy and great option even for people who want to go VESC. As it is, I feel like it might not be a bad recommendation to just tell people to buy that and change the ESC if/when they want.

On the other hand, I’m a cheapskate and have done well buying other people’s stuff. That is probably the best way to get in to DIY IMO. Buy someone else’s stuff for probably half what the parts are worth, take it entirely apart, put it back together, and then start changing things.

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:100:
This is what I did, probably around 75% of my board is from people on the forum, it saved me around 600 USD.

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Man, you read my mind. I don’t want to delay being able to ride, so I’ll just do a channel truck build. But then having the board there, I had planned to look into suspension. I was going to buy the horizon or the nyx but I just feel strange relying on all proprietary components for something that may wear out.

I really need to learn vehicle dynamics, specifically suspension types and techniques.

Plus, how will I know if it’s any better than non suspension if I don’t go with channel trucks first!

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This definitely tripped me up. I really had a hard time trying to figure out how to get the tilt of the deck to translate into the turning of the wheels while allowing the suspension to move up and down without toeing in and out each wheel. I never did figure it out except that short A arms don’t work very well.

That’s actually one reason I grabbed the Propel and another suspension board when I had the chance, I wanted to see in person how they did it.

So I’ll be keen to follow your build log. Please generate a build log for this project :slight_smile:

I still love my old mountain board, won’t retire it. I predict you’ll end up with 2 maybe even 3 boards before it’s all over…

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Unfortunately esk8 is quite fickle in terms of vendor longevity.

There’s a good chance that ANYTHING you buy this year may not be around next year.

Ideally you need to be comfortable with the fact that if something breaks, you may not be able to 1:1 replace it

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In curious if rotational dampeners can be used, I was going to look at that route first to see if it’s even feasible, but picture something like those Boston dynamics 4 legged robots… maybe?

I suspect the suspension will be much later, but I will definitely keep you posted dude!!