Sounds like a terrible idea lol
If you put them in series you’re effectively creating a 2s battery, which would double the required voltage.
You could charge them in parallel but they need to be exactly the same voltage before connecting, and that would half the charging current across the two batteries
anyone to troubleshoot a bad bms?
The answer to the question precisely as asked is “yes”. However, you will mostly only ever have two identical batteries in theory and thought experiments and not so much in real life.
You really need to charge them in parallel.
Also connecting batteries in parallel has certain dangers so make sure you understand them. Once you connect them together, leave them connected. Make sure they are both at the same voltage when you first connect them together.
You could probably charge them in series once or twice, but they will probably need to be balanced going beyond that. The more visibility you have into the individual series element voltages, the less bad it is. If they are smart BMSs and you can see all the pack voltages then it may not be a big deal. It could present some safety risks and you NEED to charge through the BMSs to ensure if one battery charges slower, the other one isn’t overvolted… and if it is, that its BMS will shut down charging (of both packs, since it’s a series connection)
Wondering the same thing. Does anybody have an answer?
First things first, I want to clarify that to get the extra stiffness you want, you have to put the carbon fiber on the bottom of the deck, not the top. Carbon fiber is incredibly strong and stiff, but mostly in tension, not compression. If it’s only on the top of the deck, that incredible tensile strength is completely wasted, because the top of a skateboard deck is always in compression.
You will need to do some prep work, sanding the surface to be skinned and making sure it’s clean and free of dust and oils, or anything else that could cause the epoxy to not stick well.
Then you would mix up some epoxy according to the required mix ratio of whatever epoxy you’re using. A good practice is to mix the two components together until you think they’re totally mixed, then dump it into a second mixing cup (disposable plastic party cups, E.G. Solo work great), and mix it for another thirty seconds. This ensures that A: there are no unmixed components stuck to the sides or bottom of the cup, and B: the epoxy is very, very well mixed.
There are lots of tutorials on the skinning process itself, so I’ll let you seek out those rather than try to condense one of them down into a short paragraph, and potentially lose some critical details.
Yea I found out I need to do the top and bottom. I’m going with the west systems 105/207 epoxy and hardener also using UD carbon fiber. I been also told that screwing the enclosure is like adding a extra layer on the board and can stiffen it as well. So might as well test that first before doing the carbon fiber, I’m hoping the enclosure test does work, but we’ll see what the outcome is
That’s true to some extent, but I personally would try to avoid that as much as possible. Treating the enclosure as structural will add a bunch of extra strain and forces to both it and the fasteners used to hold it to the deck, which neither are designed for that.
Better to let the enclosure float as much as possible (oversized mounting holes and large flat (“fender”) washers to allow the enclosure to shift slightly with the flex while still being clamped to the deck.
What kind of those should I get. Would it stiffen the board or would I have to add carbon fiber still
What are you referring to?
The enclosure should ideally add zero stiffness or structure to the board. If you want it stiffer, you will need to add carbon.
alright. And I was asking what kind of bolts I should get for the enclosure, also I was told that carbon fiber interrupts radio frequencies and can short electronics
My general recommendation for any fasteners on an esk8 is that unless there’s a good reason not to, they should be
I used M4 socket cap head screws, quite a few of them.
You’ll need some way for the screws to attach to the deck. Threaded inserts are the usual way to go. Lots of discussion already about those on here.
Yes, it can. You should be ok with regards to radio interference, since the signals can get out through the enclosure. You should definitely be cognizant of the chance of a short between any exposed electronics and the carbon on the deck though. Foam, fishpaper, or other barriers can be used to ensure that doesn’t happen.
Alright. For my enclosure I’ll have foam over the opening so I think the shorting shouldn’t be a problem, can you paint in carbon? Was wanting to add my graphic back on there and I think the carbon would be a good background for it
Yes, you can paint on the epoxy. You won’t actually be painting on the carbon itself, because you want the carbon fibers to be totally encapsulated in the epoxy resin (this also helps protect against shorts).
Just treat it like you’re painting plastic, or a fiberglass boat hull, and you should get decent results.
Alright. Thank you, as a beginner of doing carbon. How easy you think it is to do it? And how fast could a person get it done?
Like most DIY projects, they’re usually harder than they initially look. I’ve never done carbon fiber, but I have dabbled in fiberglass a bit, and I will tell you, that it is really easy to do bad, ugly fiberglass. It’s definitely harder to do it well and make it pretty.
Between all the prep work, the multiple layers and coats, the drying times in between, and the cleanup/finishing at the end, I would expect this to take a solid couple days to do right. A weekend or two, I’d say.
Follow whatever instructions you decide to follow closely, and don’t rush things. If they say to wait 6-8 hours, wait 6-8 hours.
I’ve been watching lots of tutorials, reading articles as well. Also the type of carbon I’m getting isn’t fragile like traditional carbon. Think it’s more stronger as well. Seems like you basically put a base coat on the board, like adhesive. Lay the carbon straight on there. Gonna have to read it again, but how I’m gonna do it. I’ll be putting it in the vacuum bag. Add three coats of resin and hardener, well I think the day I pull it out of the vacuum I trim it out, then add the three coats. I know I’m missing some details but it seems pretty doable
One more thing I should emphasize:
Composite dust is NASTY. Seriously, don’t screw yourself. Work wet whenever possible, and wear respiratory, eye, and skin protection. Carbon fiber splinters are awful, and carbon fiber splinters in your lungs is even worse.
Wym work wet? And yea I wear protective gear in general, even when I was adding loctite to my motor mount I was wearing gloves and a mask. I love doing this kind of shit. Learning new things also but health is safety number 1 for me. I take that very seriously, even if I didn’t know that, I would still wear a mask, goggles and gloves when working with carbon
When cutting, sanding, filing, etc, you want to keep the dust down however possible. Dust extraction (shop vac) is a great idea, but an even better idea is to not make airborne dust in the first place, if possible. Use wet/dry sandpaper, and keep the paper and the work wet while you’re sanding. That kind of thing.
A good example is people making carbon fiber drone frames. A lot of folks will run their CNC routers flooded so the carbon fiber sheet is under a layer of water while cutting.
Obviously it’s a terrible idea to use water with regular power tools that aren’t designed to be safe around water, but hand tools don’t really care, and cordless stuff is usually fine as well as long as you make sure they’re fully dry again inside and out before putting them away.
Wouldn’t the wet sanding ruin the deck. I know that from experience from skating in wet conditions that it messes up the board