A Hummie Hubs & Deck build

DavidC · June 17, 2023, 9:09pm

So I participated in Hummie’s Kickstarter campaign in 2019.

At the time I also bought the ESC (Flipsky FSESC 6.6 dual mini), battery (eskating.eu 12S3P 15Ah Li-Ion with 80A BMS) and fiberglass enclosure from @BigBen.

I stored them until a few weeks ago when finally I received the parts.

Everything seems of excellent quality. I am very satisfied.

I started by drilling the holes to attach the enclosure to the deck. I used hot glue to poke the two together.

My Li-Ion pack is a little wider than the compartment dug in the deck, so I bought a router which I used here for the first time… I had to put some wood filler back in on one side…

I coated the inside of the enclosure with Shoe Goo.

Once the wiring was done, when the smart BMS was first switched on, an ESC capacitor exploded. The ESC still worked. I removed the capacitor, which wasn’t easy as it was cast in epoxy resin.

I ordered new ones from AliExpress, but I won’t receive them until August…
https://fr.aliexpress.com/item/4000746324994.html?spm=a2g0o.order_list.order_list_main.33.21ef5e5bt5OxhF&gatewayAdapt=glo2fra

So I finally bought new Flipsky ESCs, two FSESC 6.7 mini Pro. I had already used two pairs on other builds without any particular concern. These are equipped with 100V capacitors instead of 63V for the FESC 6.6 dual mini.

I replaced the smart BMS switch with an XT60BE-F port, and added an XT90E-M on the circuit to avoid new problems.
https://uk.aliexpress.com/item/1005004166086908.html?spm=a2g0o.order_list.order_list_main.57.21ef5e5bt5OxhF&gatewayAdapt=glo2eng
https://fr.aliexpress.com/item/1005005435104056.html?spm=a2g0o.order_list.order_list_main.63.21ef5e5bt5OxhF&gatewayAdapt=glo2eng

I machined holes on an aluminum plate to attach the ESCs together.

I added a fuse to the charging port.

I added rubber washers to the fixing screws of the enclosure (https://www.amazon.fr/dp/B06XQMSLQN?psc=1&ref=ppx_yo2ov_dt_b_product_details), and a gasket all around with black Sugru. It was not the best choice for the joint, because it is not liquid enough and it was therefore a hassle to spread it.

Grip is DopeGrip Pro :

Here is the final rendering:

I updated the firmware to 6.02 following Flipsky’s recommendations (especially the disabling of phase filters), in particular to benefit from the new HFI.

I set each ESC’s Battery Max to 40A, Battery Min to -20A, Motor Max to around 35-40A and Motor Min to -35-40A. The Absolute Max must be increased to around 100A otherwise the HFI triggers ABS Over Current faults.

It starts without cogging, including when climbing.

As @Hummieee advised me, I use it as a front wheel drive.

It’s flawless. Free rolling downhill, while retaining the ability to brake, is what I like the most with hub motors.

I use this remote control from HotRC: RC DS-4A.
https://fr.aliexpress.com/item/1005004963118061.html?spm=a2g0o.order_list.order_list_main.158.21ef5e5bt5OxhF&gatewayAdapt=glo2eng

Cheap, solid, reliable. It’s also prettier than the GT2b I’ve been using so far.

In short, I really don’t regret having trusted @Hummieee. Many would have kept the money and disappeared in the face of all the problems he encountered (COVID pandemic, etc.)

rusins · June 17, 2023, 9:47pm

Man actually patiently waited 4 years for his esk8 parts to arrive

The final board looks amazing!

You have the double stack enclosure, correct?

ShutterShock · June 18, 2023, 1:33am

Very slick! Great little build, fwd is super interesting. I’ve never tried that before, I feel like it would feel kinda odd

JeffyJ · June 18, 2023, 2:11am

Great build. Very clean!

Arzamenable · June 18, 2023, 4:38am

Your build looks great! I was going to say FWD would really put those fins to use… I see, how does it feel? I would guess breaking traction is easy , but they are wide bois.

Me: I feel attacked.
Also me: googles: filetype: step, joystick

BigBen · June 18, 2023, 6:04am

Double stack for 4x4!

DavidC · June 18, 2023, 9:39am

Thanks!

Link to rubber washers added :
https://www.amazon.fr/dp/B06XQMSLQN?psc=1&ref=ppx_yo2ov_dt_b_product_details

Yeah “double stack for 4x4!”

I wanted to go AWD at the beginning to prevent the hubs for heating but @Hummieee told me it was heavier and not necessary.

So I have another build with RWD and lipos :

FWD doesn’t feel odd comparing to RWD. It makes me feel safer when going on bumps. Turning also feels easier and more natural.

walnuts · June 18, 2023, 2:56pm

im wet.

Shadowfax · June 20, 2023, 5:26pm

Congrats - this build is gorgeous. I’d love to hop on it for a ride!

DavidC · June 28, 2023, 2:01pm

Motors were 65-70°C at the end of the ride. It was a hot day : 34°C.

This build weighs 12.2 kg with Li-ion 12S 15Ah. My lightest mountainboard is 13.5 kg with Lipo 12S 6Ah.

DavidF · June 28, 2023, 2:23pm

This damn HFi sound, you must have killed some dolphins on your way

DavidC · August 16, 2024, 10:30pm

Today, after a few very brief unexpected bursts of acceleration but which should have made me stop everything, my build based on Hubs from Hummie (the one with big aluminum box on rear) suddenly went to full throttle.

I was ejected almost before I feared hitting my helmeted head on the ground.

Fortunately, the remote control from HotRC RC DS-4A automatically ejects its batteries when hitting the ground because the small hatch opens…

While dismantling the mess, I discovered this:

The coaxial cable was crushed between the carbon fiber plate (sandwiched between the ESC and the Lipos) and the interior of the aluminum box. The central conductor was therefore in contact with the braid.

However, I was not able to reproduce the malfunction once I arrived home. I tried to rub this damaged coaxial cable everywhere, but nothing happened.

Does anyone know if this can explain what happened?