Hey guys, i know a ton of people here use the GT2B, so im wandering if anyone has a spare trigger pot from a dead remote that you’d be willing to part with. Let me know!
Thanks!
If you already have a GT2B that has a dead trigger…you can swap it for the second one which should be the turning wheel used in RC cars…it is the same kind of potentiometer 
The shafts are different lengths, doesn’t work
I’ve tried that… Either bending the leads or soldering too hot ruined the connection between the pins and the carbon tracks on the original… The potentiometer from the steering assembly has a 90° rotation instead of 50°, which gives it the wrong offset. As you may note, the brake travel is shorter than the throttle travel, and the microcontroller is tuned to compensate for this- with the 50° pot, that is.
I’m currently looking for a replacement, too. I have no clue how do fix this and use a normal potentiometer, however you can get pretty close if you add variable resistors to the supply lines and tweak them… But it’s superficial, and barely works half the time.
Im working on a drop in 3d printed replacement with hall sensors, not sure when it will be done tough.
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Interesting!
By drop in, I assume you mean it will output the same analog range as the potentiometer, and fit the GT2B / Modded case housing the same?
The second pot in the GT2B works fine. Depending on whether you’re using a modded enclosure, you might just need to dremel off some of the longer pot so that it fits.
It works alright, but it doesn’t have the right offset. You don’t get the full travel on braking
You have to play around with it in BLDC tool a bit but it’s doable, pretty sure I’m getting the full range on mine. Using the other pot is obviously a little bit easier if you can source one though.
You end up clipping the signal on one of the ends to get 0 to 1 range, which is far from ideal.
That’s exactly what i’m experiencing. 1500 is still the physical center and I get 2000 microseconds on the high end, but I can only get 1300 microseconds on the braking side… Even adding varistors to either side of the pot to supplement the offset doesn’t help… If only BLDC tool could do some mapping to allow for an off-center midpoint…
You can try the Extended BLDC tool, that allows you to set min, max and mid points. It’s a good way to make it work with non symmetrical signals.
That’s my next resort- But for now, adding 5k on one side of the pot (I forget which side) and tweaking the internal potentiometers gives me a range between 2000 and 2400 microseconds. But most importantly, it works out that the center is perfectly at 2200 microseconds.
How many have broken trigger pots? I’m currently talking to the manufacturer of the pots and he can hook us up with spare pots. They are manufactured and shipped from China so shipping will be $35-50 with DHL express so I guess we have to do this as a group buy if we’re doing it.
I’ve broken like two of those trigger pots. When you say spare pots are you talking about the whole assembly like the trigger, pot, and wires with connector?
awesome! I may have broken… like 10 !
Nope, just the pot. I’m just calling it the trigger pot since there are two pots in the gt2b and the pot for the steering wheel is different.
I broke 1, but id like some spares.
Removing the actual trigger from the pot seems difficult have you done it before? Does new pot have wires at least because soldering is how I messed up the ones I had
To get the pot out of the gimbal assembly it’s simple. just unhook the spring with needle nose pliers, then slide off the trigger. The exposes a small bolt. Then the pot just slides off the plastic bits.
As for integrity of the pot, I’ve noticed two things: When desoldering the original PCB from it (to fit it into enclosures, etc.), it’s tempting to bend the leads, but I think this sometimes breaks the connection between the riveted pins and the silver traces on the pot’s PCB. Second, is heat sensitivity. Capacitors, for example, are extremely heat sensitive (electrolytic, especially) and you should be quick. I don’t know how quick is ‘quick’, exactly, but I wouldn’t feel comfortable soldering to the bare pins of the pot when it’s riveted to the board like that for more than say… 1.5 seconds? Any decent Iron with a chisel tip should work.
Also, mind your temperatures. For a sensitive job like this, I would keep it as low as humanly possible (310-330 for lead-free), while still making the joint within the 1.5 second margin. You can either solder hot and quick, or cold and slow, but it’s usually safer to end up soldering too cold and raising your temps, than to solder too hot and realize that it’s burnt up already.
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