Potential new deck build project. Mountainboard/Esk8. Project Regicide

CHAINMAILLEKID · April 28, 2025, 5:32am

Its the end of the snow season, so I’ve wrapped up my snowskate builds, decommissioned the press setup and the molds for that, and I’m ready to start something new.

Spent last night in CAD, taking measurements off of old builds, scrapping together some geometries, this is what I’ve come up with.

At the moment all I’ve got is a bunch of pretty pictures, and a handful of new ideas.
But I’m definitely going to be making something from this.

Radical board with ALL of the shape.

Black wasn’t the best choice to show off the curvature. But you can still make it out.
Got some deep bowls here. Each foot platform is about 11mm deep nose to tail, and ~15mm deep rail to rail. With some little flares at the nose/tail.

Polyurethane fenders to keep your feet from straying off? Yes Please!

I think there’s something missing. I mean, I can see where the trucks mount, but that can’t work can it?

Ah, well.
Its actually a platform deck, designed for Brackets.

Cut-in grooves to retain a simplified bracket is a cool idea, but… That’s going to reduce how strongly the foot platforms attach to the stringer too much I think.

Second simplified bracket concept. Top and bottom of bent sheet metal.

Will this bracket construction be strong enough? Maybe. I’d like to get away with keeping these parts Aluminum. I’d also like to avoid having to weld them together. Would be more ideal just having them tied together from the mounting hardware. But, welding might be inevitable.
Should be simple enough to execute with a plasma cutter and a vice.

That’s as far as I’m at right now.

Specs of this current version:
23" Long Platform.
12" Wide.
37:28 Nose/Tail Angles.
34.5" Axle to Axle Wheelbase.
Anticipated Turning Radius: 1 Dime.

TimR · April 29, 2025, 12:41pm

You’ve lost me at this bit. Is that like 20mm? That’s ultra TaF!

CHAINMAILLEKID · April 30, 2025, 12:22am

I mean, it will turn on a dime.

I didn’t figure out exactly what it would be but I’m thinking it will be able to circle within a single lane.
So 5 foot radius or so.

Flyboy · April 30, 2025, 3:42am

Very pretty! I’m interested to see how the complex curvature is gonna happen.

CHAINMAILLEKID · May 1, 2025, 2:30am

The complex curvature will happen through the art of mechanical persuasion.

Here I have the mold blanks being pressed up.

Should be able so cut out the molds this week, I hope.

glyphiks · May 1, 2025, 8:04am

I was super impressed with how well my 3dp mold worked for my step bro build. It wasn’t an insignificant amount of filament but the mold was definitely capable!

Im assuming you have access to a cnc router? What material will you cut the mold from?

CHAINMAILLEKID · May 2, 2025, 12:39am

On my previous mountain board build, which this is borrowing a lot of geometry from, I used 3D printed molds for the foot platforms, and that worked super well.

This is what that looked like. You can see the stringer mold in the center, and one of the 3D printed mold halves on the right. Held up really well, but it was more of a time/filament investment than I had anticipated.

Yes, I have access to a CNC router, and its practically cheating.

Mold is made from really bad scrap plywood.

One of the benefits I’ve found from CNC over 3D printing molds is I can just re-mill the molds down a bit if I want to change the shape at all. Where as with 3D printing, basically any change is a whole new print. So even though it does work pretty much just as good as a CNC mold would do at getting a particular shape, its a lot less flexible.

Also, being able to glue together scrap for a mold blank makes experimenting feel less costly vs having to use up filament.

CHAINMAILLEKID · May 7, 2025, 3:22am

Pressed a board today, This was the layup.

This is easily the most complicated layup I’ve ever done, and resulted in half an hour of pure chaos. But I think it probably turned out good.

We will know more in two days.

This is quickly moving out of the “Potential project” category.

CHAINMAILLEKID · May 9, 2025, 12:11am

Fresh out of the press, turned out AWESOME.
Bit messy, but should clean up easy enough.
I’ll have to figure out a way to keep things cleaner for next time.

Glue lines all look really good. A bit of misalignment, but not bad.

Now with the foam removed. Just a hollow carbon fiber core.

So the idea here is actually a carbon fiber torsion box. And the fabric I used is biaxial +45/-45.
That, plus having it formed dimensionally should provide tons of torsional strength, while still hopefully allowing some flex of the deck.

When I noticed I could fit this torsion box in between the bolt pattern of the truck, I realized I could make the whole thing hollow.

High Centering? On this deck? I think not!

Making the brackets is next. We’ll see how that goes.

CHAINMAILLEKID · May 10, 2025, 3:36am

There’s the brackets made. The bending was way more straightforward than I was expecting.

Mounted up on the deck.

And there’s the deck again after a little bit of trimming and cleanup.

Brackets are off to be welded. I can’t do any welding myself unfortunately.

Hopefully in a few days we’ll see it all put together with trucks and wheels.

I’m not super confident ATM that the bracket design is going to be strong enough.
I didn’t dare even step on it without them getting welded up first. I could just feel it wasn’t solid.

But if welding them doesn’t work to make them strong enough, I think we’re only minor design changes away from some something super solid.

CHAINMAILLEKID · May 21, 2025, 3:04am

Board full assembled (for now…)

Complete with grip, fenders, my latest trucks, which are incredible in terms of lean, center, and control. And the best/fastest 8" tires that were ever made, Ground Industry Mak’s

Took the resistance off so it would stay leaned over for pictures.
This thing is going to be a beast, just look at it!

And Riley, getting ready to launch off into space with it.

The brackets are weak sauce. We’re going to need to fix that.
We’ll just band-aid fix these ones, and then come up with a new design for version 2.

But everything else is Awesome!

This is on track to be one of the sickest boards of all time.

I think I’m going to go ahead and press up some more.

fujio001 · May 21, 2025, 7:15pm

Here is an idea. Make a one piece aluminum spine. I believe some type of aluminum can be bent while still retaining the majority of it’s stiffness.

Mount the deck to it.

A spine could probably be made of carbon fiber too.

fujio001 · May 21, 2025, 7:16pm

CHAINMAILLEKID · May 22, 2025, 2:57am

A one piece spine is what I’ve been using in the past.

The main problem I had with it was, getting the foot platforms attached to the spine in a really robust way that didn’t have any wiggle, squeak, or flex was a real pain.
And those foot platforms are your control interface, their connection to the spine needs to be just rock solid.

There’s a lot of good things about doing it that way. But I’m a little bit spent on it.

I think the reasons why I’m wanting to go with brackets is:

-I’m into the way it looks right now.

-I’m enjoying messing around in the sheet metal workspace in fusion 360.

-Once I have a method that works, I can try different designs and different steering geometries relatively easily without having to do another board layup each time. And could even have them made at a local sheet metal shop if I want.

CHAINMAILLEKID · May 23, 2025, 6:55pm

We’ve decided to jump right into the electrification.

And along with that, I’ve come up with a name.
Project Regicide

Here’s what I’ve cobbled together so far for my parts list.

Motors (X2):
Flipsky 6374 140KV

Drive Train & Stuff:
-Boardnamics MBS Matrix III Motor Mount Set (with idler)

-80T Wheel Pulley (3D Printed)

-12T Motor Pulley

-Rockstar Hubs

-MBS 8" T3 or 9" T2 ( undecided )

Trucks:
Other Planet M1
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Deck:
This deck dummy. The one this thread is about.

ESC:
MakerX DV6 100A Cont, 180A Max Per Motor

Telemetry:
Voyage Minnie

BMS:
DALY Smart BMS LiFePo4 15S 100A

Parts I still don’t know what I’m doing:

Battery.
LiFePo4
Targeting 400+ Wh Probably no more than 600 Wh
Will depend on enclosure and cramming and cell size.

Remote.
I just know I want to have a dead mans switch.

Considerations

First of all, I’ve got a Lipo board for the first time after having a boosted forever.
And I very quickly came to a realization. Voltage Sag makes me very sad.

It also really cuts into the effective range when doing aggressive uphill. I’ve got like pretty significant battery left when my current board, The Empress starts struggling to get to the top of the runs.

So, LiFePo4 or bust.

Which brings me to the first problem.

I have a voltage mismatch going on. a 15S LiFePo4 BMS, and a 12S Lipo rated ESC.
It doesn’t seem like DALY has a 14S LiFePo4 BMS.

12s Lipo peak voltage is 50.4V (what esc is designed for)
15s LiFePo4 Peak Voltage is 55V
And ESC absolute maximum it can handle with voltage spikes, I’m surmising is a Hard limit of 60v. And I’m guessing that 10V buffer is important.

Is a 5V buffer still safe enough for spikes? Can I resolve this by limiting the peak charge voltage on my BMS? Or can I resolve this by configuring my BMS as a 14S?

Second Problem.
I still haven’t figured out what I’m going to do for my cells. I’m looking at options for used cells.
Most discussions I’m finding on sources have dead hyperlinks.

I’ve decided to go with a Matrix 3 motor mount. And I’ll just adapt the trucks to be Matrix 3 mount compatible. If there’s hardware that’s likely to be supported for a long time and not just disappear in a few years, I think Matrix 3 hardware is on that list.

Why such a high gear ratio?
Because telemetry on my current board suggests my average speed when hitting the trails is only 10mph. And it seems like I get much better traction and power consumption hill climbing slower than 15mph. My top speeds down the trails aren’t using power at all.

tech.shit · May 23, 2025, 6:56pm

Which king do you intend to kill?

Has the design updated at all? I haven’t seen you post a video about the OP1 trucks recently

CHAINMAILLEKID · May 23, 2025, 7:14pm

The plan is, each of the decks I make are going to get a face card to distinguish them.
The King, The Queen, the Jack, Etc.

So its not just the king, its referring to royalty as a whole.
The royalty being referred to will actually be the decks themselves.

Bonus: The Empress board I bought is a reference to tarot cards, and fits into this scheme out of pure coincidence.

I’ve just been playing around with the expansion rate of the resistance bands is all.
Which is just moving around the locations of pins.

Really need to get more ride time on them, which should be helped a lot by this project.

Dinnye · May 23, 2025, 9:35pm

My experience with MakerX stuff is they are reliable only until you keep within it’s limits. I’d say 55V is no go. Also probably it throws faults at 57V not even 60. Even just the sag from braking close to full charge could hit that, and then we didn’t leave any space for actual voltage spikes yet. I also wouldn’t recommend charging above 3.6/ cell, there’s not much point anyways. Conveniently that at 14S is exactly the same voltage as 12S lipo/liion so you can just use the charger from your other board.

What you are talking about actually is not sag, but just the curve being flatter. Sag itself is actually worse on LiFePo4 due to the higher internal resistance of the cells.

I recommend LLT / JBD BMS if the Daly doesn’t work out. The one which is configurable from 10S-17S. I am not familiar with the smart Daly.

SirVesa · May 23, 2025, 11:35pm

I’ll second what Dinnye said about using a different BMS. I used to use Daly, but they changed the design. The newer smart BMS model had a parasitic drain that completely killed my brand new pack before I could even use it. Then again, this was li ion, not lifepo. Have built two packs recently with JBD and zero issues. The app is a lot more intuitive than Daly too.

tech.shit · May 24, 2025, 12:42am

On this note, people should be using Overkill Solar for their JBD/LLT BMSes as it’s superior in every way.