well, few days later
idk if you’ve seen last video by Martin on wintergatan channel - I feel somewhat similar way. I prioritized looks (re44) before functionality. If I did this again (which I might do, something similar), I’d do it a bit differently, full bent aluminium, minimum of complexity. something like the cybertruck
I have a question that i was wondering regarding ur build so ik ur using the huge custom metal sheet to hold the pack and pretty much everything but how will all that weight affect the ends of the deck where ur trucks are mounted? I dont think itd be a bad idea to maybe fiberglass the deck top and bottom to add extra strength to it to counter the weight and pressure from the massive pack underneath it. @michondr
This scares the fuck out of me…
Have you run any simulations on the flex dynamic of your deck/chassis combo?
Even the slightest bit of flex could be catastrophic for this pack given the way it is built with the nickel running the whole length…
@dani this seems to be right up your alley, what do you think about the strength of this chassis and it’s likelihood of flexing?
This board is a power wall with wheels that you can ride
I think the whole idea is a bet dynamics wise. Me thinking the chassis w/ batteries will have a life of its own, it’s way flexier than the deck.
You can run some calcs to see how it will handle
week 8 of semester (out of 13)
finally got some time. my depression from not having this finished is going throught the roof. my trampa has problems with battery and one sprocket, so I guess my stress anxiety is going to rise and I’ll be forced to make something work, so I might aswell pour the time to the painkiller
I also had to file down the 3dprint, that took some time. I need to source longer bolts, I’m short on M6x100, so I’ll try to get some nice torx M6x110.
I need to install battery stops, propper mount motor cables (filed and sanded holes) with MT60, heatshrink through the hole, chisel routes for the cable to underside of the deck, attach cables, solder jacks.
then the rest of electrical - flexibms (need to chain power from somewhere, forgot one cable from battery), metrpro can, remote, davega (shit now I realised I need to route the cable 
), charging ports, power switch
then all the software, calibration and tweaking, making the CAN work, bla bla bla
probably will do the LEDS later, same as the USB-C for the helmet camera&lights
good question - thought of that, the enclosure rides directly on the trucks and the deck is only for the lateral force
what my brain thinks is that because the enclosure is strongly bolted to the deck, it might be more in tension and the deck in compression. naturally there will be some bending becuse as a rider I stand between two fixed axiles, and some movement might occur. but nonetheless the whole build will be a different universe of flexi comapred to my boosted or trampa.
individual suspension would be very nice with this much momentum on road.
you can run calculations for this? 
I’d guess that’s possible, but I’ve never seen anybody do that
guys what kind of duo are you? 
I like you
I’m quite optimistic when the two parts will be one rigid body. the alu alone would be bad, it seems to give after some time under load. I had it laying on the bench for a few weeks with the battery in, and it seems to have permanenetly flexed a bit.
you’re right, that very optimistic. we’ll see how rigit it will actually be. I’ll be doing some jump tests without and with the battery, with all bolted together, to see if it flexes, and if so, by how much. better to test it in a controlled environment than experience it on road
good insight guys!
I think your chances of success would be much higher if you could introduce proper stiff walls between the chassis and the deck 
the fbi wondering why you bought 350 battery cells
Sure
How interested are you?
Dude this build is getting more and more scary for each time you post it, just the size of that enclosure and your ground clearance, I would stick to 9" tires minimum, one pot hole and you will have 10s28p suddenly 
.
I hope your build gets a test ride soon 
Yea i think some wide offset 8 to 9" would really do this build some justice especially since u have over 6kw using 8 or 9" tires not gonna put any damper on ur mega range.
the 3dprint wall seems not stiff enough?
I’m on the same side, I’ll be definitelly switching to 8" after a first ride, but larger wheels are not easy atm, as the 3ds rims I have top at 8". I’d have to get bigger ones
If there’s enough force to flex the deck and that crazy aluminum sled, it will shatter a 3d print in short order.
How about metal standoffs between the aluminum and the deck? Then you can use 3 printed parts but have the rigidity of the standoffs
If the goal is to make the structure really stiff in bending, standoffs won’t work because they have high compressive stiffness only, and the connection between the deck and aluminum needs high shear stiffness.
A continuous sheet of material connecting the upper and lower pieces would suffice, or a truss type structure with lots of diagonal rods.
With @michondr we agreed to put forward some colorful pictures of the dynamics of this one, especially after my remark several posts up.
The first thing to consider with dynamics is (well) the dynamic properties, i.e. natural modes and frequencies. So after approximate modeling of this scary tray and putting in 23kg of batteries these are the results:
We’re getting two distinct modes of the tray below the actual deck (the deck is around 90Hz), what it means that with bumps in the road the tray will get excited by itself. Not healthy.
Normally you’ll want the whole structure moving together so no relative motion will happen. I would consider tying the two parts together, standoffs might help, solid walls are better.
Dani
