No lateral force. There’s a picture in pictures only thread with a motor going to fuck, having a circlip eaten .
Other than that, the sound. You do want to bring some awareness to others around you of your presence, plus, i at least, like how straight cuts sound
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You can make smaller spur gears for the same tooth size and count. They’re also very cheap to make, and don’t produce an axial load unlike helicals.
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They are already in a series connected by xt 90 connectors.
I’m not quite understanding what you mean with the balance leads. I’ve rearranged pins and whatnot before, but I can’t visualize what you are explaining .
I also have to consider the space for the BMS and figure out what charger I would need.
Honestly if I could just figure out a way to charge my lipos without having to open the enclosure id be happy. I think a BMS is the only way to accomplish this though.
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Yes, a BMS is what you need.
Ok I’m gonna take another run at explaining this with words before I have to bust out pictures 
You have two LiPos. Both are 6s. Both have a balance lead coming off them, with 7 wires. The first wire on each balance lead connects to pack negative. The last wire on each balance lead connects to pack positive. The wires in between connect to each cell. If you measure the voltage between two adjacent balance leads, it will tell you the voltage of just one of the cells in your 6s pack.
The problem is, a 12s BMS (usually) has 13 balance pins. On a normal 12s pack, this would connect to pack negative, and then the positive of each cell, for a total of 13. Here’s a picture:
So you need to turn your two 7 pin balance leads into one 13 pin BMS connector. The first step in this endeavor is going to be buying a BMS. I suggest this one:
Once you have your BMS, you need to wire up your BMS connector, turning your two 7 pin connectors from the LiPos into one 13 pin connector.
The way you are going to do this is by assigning each balance lead to one of the leads on the BMS connector. I am going to describe which pin goes to which below.
L1 is your first lipo in series.
L2 is your second lipo in series.
BMS is your BMS
P# is which pin I am referring to.
L1 P1 -> BMS P1
L1 P2 -> BMS P2
L1 P3 -> BMS P3
L1 P4 -> BMS P4
L1 P5 -> BMS P5
L1 P6 -> BMS P6
L1 P7 -> nothing, clip it off, isolate it.
L2 P1 -> BMS P7
L2 P2 -> BMS P8
L2 P3 -> BMS P9
L2 P4 -> BMS P10
L2 P5 -> BMS P11
L2 P6 -> BMS P12
L2 P7 -> BMS P13
The reason you are going to clip L1 P7 is because it is connected directly to the negative of L2, so it will have continuity with L2 P1. That means it has the same voltage. As far as the BMS is concerned, L1 P7 and L2 P1 are the same wire. So one of them has to go.
Before you plug your new 13 pin BMS connector into your BMS, take your multimeter and place your negative probe on the first pin, then measure each pin going up the connector with your positive probe. If you have made your BMS connector correctly, you should see the voltage count up on each pin by the amount of voltage per cell (4.2v per cell if it’s fully charged)
Does that make sense?
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Could I unfuck this by filling in the hole with jb weld and re drilling? Or do I absolutely need to do another layup of fiberglass?
I taped and marked the holes to line everything up but clearly I suck at this
I have two chargers. One is 4A and the other is 7A. I have a freshly made 12s3p 40T pack with a bypassed 13s daly BMS with the last pins shorted. The BMS is rated at 8A.
The 4A charger will charge my board every time no problem. idk the brand,I borrowed it from @Brently
The 7A charger will not charge my board. This one I have 4 of them and all of them behave the same. See the video below.
Also, I remade the xt60 to barrel adapter I had; just to be sure it wasn’t something I fucked up.
This is the BMS I used.
TIA for the help guys
Anybody know the thread/pitch for the trampa spring adjusters?
M7-1
Have you confirmed that the 7A charger in question works on a different battery? Im thinking its either your charger or your BMS. If your charger is known to work, and your BMS works with the 4A charger, then i think what’s happening here is that you are running up against the BMS’s current limit.
“But Duck, this BMS is rated for 8A, it says so right on the side there.”
Yeah, well, china. Your charger might be putting out more than 7A, or your BMS might not actually be capable of its rating. Either way, the specs are misleading.
I feel this is most likely bc I have 4 of these brand new and they all behave the same.
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Yeah seems likely to me. Anyway, looking to sell some 12s 7A chargers? 
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JB weld (Or any epoxy/resin/adhesive) has very little strength on its own. You need some kind of reinforcement, be it fibers or a backing plate to support the forces you will be applying by drilling a new hole.
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Yes that makes a lot more sense. The extent of my experience with battery alteration has been changing the connectors to xt90’s, and making a series harness.
Essentially, I’m just trying to make sure I don’t blow myself or my house up haha.
I also meant to ask if this method bypasses the discharge management.
“bypassing discharge” refers to how you wire up your BMS, not to the balance leads. There are several diagrams floating around on this forum that you can find that describe how to bypass a BMS, but what it basically boils down to is that your main pack leads to your ESC’s are just wires running from the positive and negative of your battery straight to your ESC’s, without stopping off at your BMS first.
Thanks. Yeah, I watched a bunch of videos right after I had posted that question to educate myself haha.
Appreciate the input. I’ll definitely by bypassing it for this build.
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I’m trying to find a bms with a 12A charge rate so I can charge at 1C
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so straight cuts don’t produce an axial load…what is exactly is an axial load? I have an abstract notion that it’s just some sort of force acting upon the gears…
I wish I could help you here. Im on that #FuckBMS life, so I dont know a whole lot of good BMS options. Perhaps you could pose this question in the Battery Builder’s thread?
In this context, it means load perpendicular to the rotation of the gear. So your motor shaft wants to slide in or out, rather than just rotating in place.
@Venom121212 learned ALL about this recently haha. He posted a good GIF in the pictures thread showing what was happening.
Edit: Keep scrolling. As usual, Ryan explained it better than me, in fewer words
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