If small stones get suck in you definitely can damage the magnets non the less, not to forget about the bearings as well.
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Long time no update here….
Need to write the latest news from my workshop up when I’m back home from vacation.
Gonna build the first board for a friend soon as well. A light weight jump board for sure, how could it be different 
Most parts already ordered. It’s now the big waiting time till all gets delivered.
I would also like to take some old lipos out of operation. @Battery_Mooch do you have any recommendations on how to best fully drain old lipo packs to trash them?
So far I never had to do that, so some input on that would be much appreciated.
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Forgive my tardy reply…
Automotive light bulbs, surplus power resistors, fans (right voltage though), anything except that preposterous saltwater method of creating toxic sludge while failing to actually fully discharge the pack.
LOL…even an LED with the correct series resistor. Just put the pack aside for however many days it takes to drain down to approx 1.8V (the LED’s voltage drop).
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I did a bit of research in RC forums and on YouTube, just… everybody is expert there and everybody tells something different which is for sure the only good way to drain your pack…
The resistor method is what I was looking for.
Things I‘m not sure about is the right load and how high is the risk that the lipo catches on fire when getting deep discharged.
The packs I have are 6s 5Ah 60c packs.
As resistor I was looking for something like this between 4-8 Ohm. Is that about right?
100W Watt 1ohm 2ohm /4 ohm
Draining Li-ion cells all the way down shouldn’t cause a fire hazard (you’re removing the energy needed to cause problems) but it’s always best to assume that it could. Do this on a non-flammable surface, away from anything that could ignite, hopefully in something that won’t let the packs fly around if they ignite (but not a sealed box that could burst!).
I think anything bad happening is a million-to-one event but since the consequences could be bad if something did happen it’s best to take precautions.
With your packs at 25V max and 4 Ω resistors you are dissipating 155W or so at the start. You will need at least 300W worth of 4 Ω resistance to not overheat the resistors unless you put a fan on them. Then you can probably run them at 100%.
This is assuming the resistors are actually rated 100W…which I can practically guarantee they are not. To make things worse that type of aluminum cased resistor can only handle its rated power (if the rating is genuine) when mounted to a huge heat sink. This is how they are designed. They can only handle a few watts if no mounted to a heat sink.
“Tubular” power resistors can handle their full rating and the tube shape lets some air down the center, helping to cool them when using a fan. I can typically run at 200% of their genuine power rating if I use a fan.
Your pack voltages will drop though and that will ease the heat load on the resistors though. So maybe just set up something rated to about the full power they will see and use a fan to keep them cool. That would mean about 150W if using 4 Ω resistors. Two 2 Ω 100W resistors in series would handle 200W and could be used.
This assumes genuine 100W ratings!
For those resistors linked to I would assume about 25W genuine power handling if mounted to a big hunk of metal using thermal paste. Be sure to remove the drill hole burrs on the bottom that you can see in the photos as that will prevent good contact with the metal plate/block.
12V light bulbs can often be the easier way to set up high power handling. They are crazy bright when running though…blazing. Two 12V bulbs in series will handle 6S packs and just parallel as many sets of those two as you want (or can deal with light wise) to increase the current.
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I have some of those lipo safe boxes I would do it in for sure.
4 Ohm still too low?
I was thinking about discharging at around 1C, that’s why I said 4-8 Ohm, but any recommendations are very welcome.
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See my edits above
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That’s about 6A start (using 4 ohm).
That sounds like a nice slow discharge. It should be okay but I don’t know the internal condition of your packs or what your setup will be so I’m not able to guarantee anything. Assume something can go wrong at any time.
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Thx Mooch for the numbers.
That already helped me a lot.
The packs still charge and discharge pretty equally over the individual cells. The capacity is slowly dropping and they are slightly buffy aand 4 years old. So thought it’s time to swap them for some new ones.
With tubular resistors you mean something in the style of that one right?
1PC RX20 High Power Glaskörper Rohr Typ Enamalled Draht-wound Widerstand 75W 100W 150W 200W
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Yes, those resistors should work. A single 5R 100W one will probably do the job if you have a good 90mm or 120mm fan you can have at one end blowing down the length of the tube. Rest the resistor on a kitchen/bathroom tile or something very heat resistant.
The resistor will still be VERY hot but probably not over 200°C.
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Just a quick warning…those resistors snap VERY easily. I recommend getting a spare or two.
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I will check our local electronics shop. They should have them and would make it easy to replace if one broke.
Thx for the warning thou.
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To my shame I need to say I did not ride the Lunas by my own yet.
So I can just give a bench test opinion which is based on static tests
Airs are proper MTB trucks, Lunas are carver trucks. For light persons the Lunas will probably work off-road till some point as well, but I don’t see a reason for doing so.
Airs I wouldn’t want to ride without bindings, Lunas should be perfect without bindings.
I think Lunas are a good choice for people who already used to ride RKP trucks on regular longboards and moving to MTB style carver.
I personally wouldn’t recommend them for heavier riders as they turn super easy even with hard bushings, but that’s just me as I don’t like too nimble trucks.
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What’s with the censored motors? Ya tease
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They are Flipsky motors. I covered them just that you will not curse me 
Nothing spectacular going on right now. Sadly close to no free time. Haven’t been riding a board for weeks… 
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You’ve got a crazy good hand with the paint jobs. What’s your technique?
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Thx! I‘m not doing anything special really. Probably just lucky with the last parts I painted.
For printed parts a bit extra time for sanding and a good primer does work wonders.
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Too long time no update here. Don’t even know what I already posted, but well… new project at work really took of most of my free time for building.
Still some big things planned for this year.
I got a set of V1 or V2 etoxx hubs I tried to install the last week on my 9“ build.
They do look so sweet, but fuck they are a pain to install really. Not sure how the design with the latest version, but I’m not really a big fan of how they are working.
The bearing seats have a slight tolerance which makes them wobble and some of the „new“ bearings they came with have been already fucked. I could eliminate that a bit by loctitingthe bearings in… we will see how that goes on the long.
Also got some idea mounts which came in raw.
They are going on my light weight build.
I‘m more or less already happy with how it is now, but here and there some new stuff is always good.
As I wanted them in black I found some guy locally who anodized them for me.
Was really surprised how quick that was.
5h and about 10€ later they looked like that.
With all parts together I can start rebuilding soon, so should be back on track till season opening.
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