Thats really nice dude 
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My fancy kick to start smart switch acted funny with Serineh on the board. Also the fail safe behavior for loss of connection changed to mild break out of no where.
Back to the basics. Loopkey and mini.
Is this print a @mmaner or @Venom121212 design? Regardless, thank you for sharing.
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Are these safe? Every spec I see online for this is 30A cont, 60A instant. Not 90A like the XT90/S. Sorry if this is the wrong spot to ask. Seemed relevant in this location.
They use the exact same bullet connectors as the standard male XT90 connector, so they should be able to handle the same current.
Amass (the company that makes the genuine XT90 connectors) only rates the XT90 and XT90S at 40A continuous. However, they have been tested and proven at much higher currents for short periods of time (minutes). It’s a general misconception that the XT90 is officially rated for 90A. Find an official Amass datasheet and you’ll see what I mean (though you’ll have to be able to read Chinese).
When Amass says “40A continuous” they mean truly continuous, as in “indefinitely.” For electric vehicles, we never pull a “continuous” amount of current. The load on our PEV’s is constantly changing, so pretty much everything we do falls under an “instantaneous” rating. That means using an XT90 for 90A peaks is totally fine. Same with these XT90E-M connectors.
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I think this is mostly true, but be careful with generalisations duck man. Other EVs like bikes and scooters are much easier to produce sustained current on.
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True, though I think I can still make a pretty good arguement that those “sustained” currents do not meet the muster of “continuous” in electrical engineering terms.
I’m no EE, but from my understanding “continuous current” means “indefinitely” AKA “forever.” It’s used to discuss the electrical losses in a conductor at a given load, based on that conductor’s resistance (where the losses come from) and it’s thermal environment (where those losses go, i.e. shedding heat to the environment).
A conductor in a thermal envelope at a continuous load will reach a temperature, and then rise no further.
How long that takes, and how hot it gets, depends on each of those factors. An 18AWG wire can handle 40A for a couple of seconds without even getting warm. But if you put 40A through it for an hour or two, it’s going to get extremely hot and possibly even burn up.
The best way I have come up with to think about this is comparing phase wires to charge wires. We all know that we can push huge amounts of amps through our phase wires. I have 12AWG phase wires (that are quite long) and I dont bat an eye at pushing 120 amps through them, because they will only ever see that much current for, at most, a minute or two while powering up a steep hill. But if I wanted to charge my board at 120A, I would probably use 4AWG wire or bigger, because the length of time is so much longer and the current is sustained.
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A continuous load is usually one that is constant and uninterrupted for 3hr or more
According to the NEC anything under 3hr is non continuous
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Well said. I see the confusion around this a lot. Your explanation here is perfect 
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Watch this video.
In open air, they desolder themselves at a whopping 300A. Even at 270A they weren’t failing. Of course we don’t typically use them in open air, but this can give you an idea.
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Nice !
Just use epoxy, it makes your life easy 
I still have to cut a hole in my enclosure which is made of ABS primarily. Only limited areas have been replaced by epoxy and fiberglass. It just kicks up a ton of plastic chunks which is annoying.
I do plan to epoxy in the male side and then use some other connectors to be able to easily remove the battery from that male side. To make it easy to completely remove the battery from the enclosure.
Normally, I don’t epoxy in the connectors and use a tight friction fit + custom made gaskets to hold the connectors and then some hot glue on top for good measure. Makes them easily removable after the hot glue is removed but still water tight. However the xt90 connectors I have are stupidly hard to insert and remove so the epoxy is needed.
You can cut ABS with a pocket knife, it’s ridiculously soft.
And actually, epoxy is a bit too hard, it will pop off the flexible ABS, although I still do it. If the epoxy is on both sides of the ABS it will lock itself in. But put some water sealant on the inside in case it separates slightly from the soft ABS as the ABS flexes.
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Weird that you’ve had that issue before because so far I’ve added onto two different ABS enclosures with epoxy and I haven’t had any sort of issues. Maybe you were just using a super soft version of ABS? 
It isn’t an issue with the harder stuff at least so long as you rough up the abs surface to ensure a nice bond between it and the epoxy. My only issue so far has been at my bolt holes where I end up accidentally tightening the nuts too far and it can crack the abs, but it only happens in some areas. Others are fine even if I tighten them down until it can’t go anymore.
I could use an exacto knife and cut the same spot over and over until it finally cuts all the way through but that destroys blades very quickly and hurts me to do.(it physically causes me pain and my ring finger gets cut up by how I hold the knife) Way easier to use a metal cutting disk on my dremel or a carving bit if I need a smaller hole. Just makes an awful mess.
Maybe there are different kinds of ABS then
I am pretty sure there is since my snake’s enclosure is also ABS and it is softer and easy to cut on the lid like what you described. Although plastic specific epoxy does have zero issues bonding with it, but I have only found that version available in the little syringes.