Oooo that’s sweet, is there a build thread?
Do you have enough space for your feet?
So, I’ve accumulated lots of GT evolve electrics and I’ve been thinking about building a mini board. I don’t like how they drop into eco mode prematurely though and despite having spare vescs, I’m still a tight arse.
I’ve found the voltage divider network on the GT ESC, and proven that the sag detection eco mode thing they do is determined off this, not the BMS reading. Also, the BMS interconnects don’t need to be used. As long as 0 and 10 are connected, the UART works, GT mode can be enabled.
Prepared to alter the voltage detection circuitry, I could stick with 10S, or try to go with 12S and if it shits itself I just stick a better ESC in.
Anybody been down this rabbit hole before? Or should I be asking for help in the mental health column?
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Sounds like fun as long as you’re willing to chase any gremlins that also pop up. I haven’t seen anything about doing this same mod but that doesn’t mean much as Ive not looked into it really.
Does it just drop out of gt mode when the battery sags to a certain level? I wonder if it is more to donwith the cells than to do with the thresholds of the protection circuit. Maybe it kills the battery as it has no low voltage protection when you scrape those components. Should start a thread for this - interesting stuff
I would keep it at 10S and always wear a helmet.
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Yeah,
Might do that. A quick bit of testing on the bench last night suggested the BMS detection voltages werent used. I soldered a couple small wires off the potential divider and powered the esc with the bench supply, gaining access to the data on a phaze remote that come with yet another $100 GT I bought last week.
Manipulating the detected voltage of the ESC was easy enough to do, so if I get so far to try this I will probably remove both resistors and run three wires out to a piece of veroboard. I’m considering using zeners to clamp voltage limits, and changing the divider circuit so they run at about 10mA. I’d need to do some ohms law between beers, but I don’t see why this should be too difficult.
The BMS cell voltages were literally floating all over the show, and that didn’t affect eco mode. I was surprised. Given the wanky marketing videos of the era, they’re really not that thoroughly developed. What did affect eco mode was changing the voltage measured on the esc, and it had a time constant type of filter that simulated having capacitors across the divider circuit.
If I make much more progress, I’ll start a thread and commit to it. I don’t want to bother building a mini board at 10S, and if I can 12S in a stoke using a GT ESC I would feel a greater sense of satisfaction. Either way, I’ve still got to make a mould and then make the enclosure before much else. Probably 12S6P 18650, and flexible segmented design like all my other enclosures have been.
The hardest part of this idea might be, that after three months of injury, I’m back at work next week travelling around fixing and installing CNC’s, saws, and edgebanders. On top of this, I’ve got to wire my new garage, get storm water in, and then still chuck another $25k at getting a driveway which makes saving $300 on an ESC seem negligible. Such is being an adult I guess.
Today, being Wednesday, is skate to the pub for lunch day. That’s a 40km round trip usually and my mate there’s an electronics design engineer. He designed and built the full radio network at Scott base in Antarctica during his six years on the ice, and specializes in drinking beer and repairing Amiga computers from all over the world. It makes the few ESC’s and audio amps I’ve repaired seem like nothing.
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Very cool, feeling the adulting pinch this month too as my laundry died and in order to put in the washing machine the wife bought i have to fix a cascade of plumbing and electrical issues in the south wall of my house. This has initiated the “walls already open, best fix it now” doctrine of scope creep and im getting all the little annoying things like uphill undersized drains and 14 awg connected to 12awg wires on a 20a circuit (didn’t know this until i opened the wall) and the absolute lack of insulation on an exterior wall and vents used as sanitary sewer homeowner special corrected.
Spent every extra minute after work just getting the laundry done and functional and now i need to finish all the rest of the crap i found and have 80% sorted out. Plumbing is a pita and im glad im done with that part at least. Gonna go drop another $500 on wire to redo the sketchy home runs and i should be only about $4k in materials all in. I call that a win
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Ugh i know that feeling so well I’m getting ptsd just reading this 
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Sounds like a mission. Renovations seem to never end like a bottomless pit. Especially if your house is entirely wooden and 98 years old like mine is.
My remote went flat coming back from a 50km skate after pub linch. I didn’t have a spare. Had to finish the ride with vesctool “controls” page with 40A on or off via touch screen.
Found all this free insulation foam, so might look at getting a trailer and bringing it back for the new garage. It’s also what I use to make enclosure mould shapes from.
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Damn thats a score! That XPS isn’t cheap!!
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Yeah, apparently it’s always available and they have to pay to dump it if they can’t give it away.
The hard parts gonna be dragging my monstrosity of a bandsaw into the garage somehow to slice and and rip them to 90mm sections.
Cheap / free insulation, but a lot of work. Results seem promising. The panels come from the local kingspan factory where they make all the roof panels, there is a limitless supply of defect sheets so plenty more to do the roof and garage door.
I have to cut all the sheets to 310mm or less to be able to rip them in the bandsaw to 88mm.
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Your workshop is gonna be microplastic massive 
You ain’t kidding! I had a hard time tonight getting that bandsaw in by myself. Had to take the table off, and the upper wheel so I could bully it in. But, I really can’t be cutting all that stuff up outside!
I work with edgebanders anyway, so I’m used to swimming in plastic swarf.
All these panels would go to landfill otherwise anyway, so at least I’m diverting most of the material and recycling. I think that’s being good.
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For sure! I’m not throwing shade! Just a fellow dust lover over here 
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I feel like this is actually better than recycling. The phrase as I know it is reduce, reuse, recycle. In that order for good reason. Looks like reducing reuse are doing some heavy lifting for those panels and your project 
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It is unbelievably dusty though, and I’m trying my best to follow the safety instructions on my bandsaw.
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A couple dirt bikers rolled up on us at a refreshment break spot today. These guys were stoked and actually took us up on our offer to try out the boards! Rare when someone says yes but that smile someone gets when hitting the throttle for the first time is always the same. They were talking about getting some MBS Agents after the demo but we’ll see.
Dirtbiker down!
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I almost never let random people try my board bc I know they’ll fall on their ass 
closest I’ve gotten is someone who used to skate but I told them they had to keep my at their side and they didn’t want to after that
I was just going to stay there so they could use me as a safety rail if needed. My board is the most unstable when sitting still or at low speeds. Surf adapters are weird like that
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I’m looking for some insight on solar power things and I know a few people who have recent experience so I’ll yell at them first @SternWake @glyphiks
I’m looking at a single 50w-200w solar panel and I’m a bit out of my depth here. I’ve tried skimming through Will Prowse’ YouTube channel and haven’t found much in regards to very low budget low output solar stuff.
Is there another (preferably unsponsored) place to be looking for recommendations on smaller scale stuff?
Do any of y’all have recommendations for small panels focusing on cheap and portable?
Is there any context I’m leaving out that would make the previous questions easier to answer?
I always put it in L or M on the remote and tell them to take it easy. Most people listen. He didn’t eat it too hard lol. Got back up and kept riding. We just never see other mountain boarders so trying to let as many people get a chance to try it out as possible. These guys were geared up pretty well too.
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