Please critique my ultralight electric "paragliding skateboard"

Hello all,

I’m building a board meant to transport me to a paragliding launch with all my gear. I need this board to be as small and light as possible because I will need to store it in my harness and fly with it.
Total transport weight will be about 250 lbs (body and gear). The road is paved and about 6.5 miles with an average incline grade of 7%.
Do you think a single 7k motor would be better and lighter, than dual 3k motors?
Any advice on how to get the most out of the smallest and lightest package would be appreciated. Budget is unlimited.

Below are the components I’ve come up with for the build.
Motor: Dual 6354 Flipsky 140kv
Motor mount: Radium matrix 3
Trucks: Slant Magnesium trucks (might need to grind to fit motor mount)
Battery: Molicel P45b 12s2p
Deck: Homemade carbon fiber with divinycell core
Wheels: 105mm Hollow wheels or 70mm iwonder cloudwheel or Seismic Tantrum 82a

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You’re going to want two motors. It’ll help the braking as well.

I wouldn’t fuck around with this. You want your mounts square and secure as it sets up your whole drive. Get the right trucks imho.

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Unless you’ve seen foam core decks work reliability elsewhere, or you’re cool with being the guinea pig, I’d worry about the foam failing at point loaded spots, or the core peeling off from the skin due to vibration. Even if it’s divinycell.

A low density wood, or even end grain balsa, would be a safer bet than foam.

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A carbon fiber deck would get you the lightest deck possible but I don’t know if anyone has made them in smaller sizes. I’m sure you can get one made or just cut up a longer deck into a shorter size since you have no budget.

The hollow wheels weigh 299g, the iwonder does not list their weight, then the Seismic are listed at ~162 g. so the hollow wheels might not be the best bet if you want the least amount of weight and the ride/road you use is mostly smooth.

Also the max weight for the hollow wheels is listed at 190 pounds. There are threads about the wheels on here you can look through to see if you’re okay risking them not holding up to the extra 60 pounds.

Boardnamics has some good small width options for trucks if you don’t want to deal with forcing motor mounts to fit trucks no one else uses for esk8. He also sells motor mounts that are shorter and will weigh less than the radium mounts. No idea by how much though since Radium does not list the weight of their mounts on their site.

It gets super annoying to have to realign everything because your motor mount moved slightly. It might not seem that bad at first but after a few weeks you will be tired of fixing the alignment.

Paragliding is something that I want to get into so bad but it costs too much and there is no where near me that would work well for it. Too much restricted air space near the areas that there is space for it then everywhere else has too many buildings

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Would advise against the cloud wheels with that much weight on them or at least do the epoxy fill on the cores. Probably better wheel choices out there

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Good point. I don’t want my belts to be out of alignment. Thanks!

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Yes, the hollow wheels are heavier, and larger diameter. The size would hurt my torque as well. The seismics are probably the way to go.

The hollows have 2 types of wheels. One will go up to 250 lbs. But I’m not going to use them now.

I’ll check out the boardamics. Thanks!

If you have water, you might try kitesurfing. That is my off season sport and it is just as fun, and cheaper.

True. There probably isn’t much of a weight difference. I was going to reinforce the loaded spots with extra layers of carbon fiber.
I’ve build a lot of carbon kite surfing boards, but not a skateboard. If it breaks, I will repair or rebuild.

Thanks for your input!

We need a weightweenies thread :stuck_out_tongue:
I love lightweight builds too. So two motors are better for braking etc but one bigger motor is lighter because you don’t need a second motor mount, pulley and controller. If you go with two 6355 check these trucks Trucks – TyneeBoard
For deck check this Louis Bradier's skateboard ditches plywood for carbon fiber. Will it thrash? - Core77

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Lightweight composite boards are possible :call_me_hand:

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That’s a good point. I was thinking of a conventional layup where the top and bottom plies are separate. The important part of that deck is the composite skin wraps around the rail, taking the shear loads off of the core.

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Honestly, the enertion raptor deck is pretty nice & CF IIRC. Might be worth looking into. Wouldn’t a foam core eventually turn to like. Dust? W/esk8 vibrations that is.

I guess eventually is the key word tho, if it’s just for paraglider launch it’ll probably never see the hours required to do that.

Magnums or Hummies custom wheels may be a good option. Smaller diameter but nice and wide to absorb.

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IMO these are all bad choices for your application. I wouldn’t trust any of the hollow wheels at 250lbs total weight. 70mm wheels are awful for esk8, and I don’t know about any belt drive adapters that would fit the seismic core anyway.

I’d consider the 105mm mad wheels. Not the lightest, but it won’t be a miserable riding experience.

DIY is fun af and you’ll learn a lot, but you might want to spend $500 on a meepo mini or backfire mini, just to pressure test this idea. They will be lighter than anything you’ll build yourself, and would allow you to try out the esk8 facilitated paragliding experience, without commiting thousands of dollars to the project.

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I used Soric on a couple which makes a core that is a bit of a mix of microspheres and resin

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That is a good idea. There is no real winter here so it could be almost year round too :thinking:
There is a river in the heart of Austin but with the bridges I’m not sure it would be a good area for it and they might have restrictions on what you can do on it?

I don’t know any brands off the top of my head, but any 90mm wheels would also work well for most roads and would weigh less than 105mm wheels. Although 95mm is better IMO since less cracks are wide enough to trap 95mm wheels

The weight difference between even just 95mm wheels and 110mm is more significant than you’d think it is. The difference can be even larger if the bigger wheel is also wider

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You are right, there should be a dedication thread to light weight builds. We pool together a list of ultra light products that we could work with.

Thanks for the links. I’ll check them out.

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Great call on the Boardamics trucks. They are the only one I saw with small aluminum trucks. Also, the shorter motor mounts were unique. Thanks!

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Even their smallest hangers - the 145mm - can fit 2x6354 motors if you’re careful, or 2x 5045 if you don’t need as much power. I pitched the idea of 2x5045 and got a few concerned looks a while ago, but prebuilts use em regularly so IMO it can be fine depending on your needs or expectations

I’m doing a single 6485 motor. We’ll see…

Ok, I need some more help.

I’m unclear on how high I can set the amps on my VESC. I got the Flipsky 6.7 which is Continuous 60A, instantaneous current 150A.
My single motor is the Reacher 6485 173kv. It can handle 74 Amps continuous and 105 Amps instantaneous.

Can I set my VESC to 74 motor amps, or will it burn up my 60 amp VESC? Remember, its all uphill, so it going to be full throttle most of the time.

If it matters, my battery pack is 10s1p Molicel P45b. 4.5 ah and 45 amps output.