Have you tried flexing the motor mount by hand? Timing belt require a really rigid setup to work, and 3D printed parts, specially thin as this one looks won’t be nowhere near rigid enough
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It’s solid, I can not flex it by hand. It’s 12mm thick.
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Ok, check also everything you can, if the pulley doesn’t flex on the wheel, even if it’s minor it can cause problems, specially in single drive boards
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Okay, I’ve been thinking about it, and I have a strong hypothesis.
I think that even if the braking power and/or current is lower during braking, it tends to skip more because it’s a big pulley attempting to spin a small pulley instead of a small pulley trying to spin a big pulley.
So if you apply the rotational force to the big pulley, it’s more likely to skip than if you apply the rotational force to the small pulley.
That’s my hypothesis on why belt drives highest stress moments are always during braking.
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If you mount is 3d printed I assume your wheel pulley is too? Have you checked it recently for wear? If your belt is skipping often I bet that pulley is getting fucked.
Are we just looking past that’s it’s a single drive and unless you’re a light rider, brakes are always lacking?
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Broke a belt at the highest point in my ride once. Scary as fuck to get back down.
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This happened on a Liftboard single drive I had. Broke going up the backside of a hill I HAD to go down going back home. If it hadn’t of been that it was a Liftboard, I’d have rode it down lol. Walked the whole way
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I expect not the best brakes for sure, and I’m 200lbs. But currently it’s dangerous. I’ve ridden the board twice now one mile each way, I slow down way ahead to keep control, but if a car were to pull out in front of me I’d have to make evasive maneuvers, I have only been riding at a speed I feel comfortable running it out in the areas where a car suddenly comes around the corner on a blind turn between my house and work. We’re talking 15mph maybe, where as on my previous build I could ride full throttle the whole way at 30mph
The pulley is printed, I had it off last night, no signs of wear after 4 miles.
Pretty sure your right on this.
I dicked around with it last night attempting to tighten the belt a bit, but with the belt tighter, I had trouble with alignment and it was late and I was two…
maybe three whiskeys into it. I’m going to try to mount the idler on the other side and not tighten it so much as I was last night. Maybe idler on both sides idk.
The motors were barely warm after the mile to work/home, and this board is definitely not for riding hard, it’s a completely different animal then my longboard, I’ll need to tweak the bushings etc to make it more stable, but as of now it will be for leisurely rides around the park with my some while he rides his hoverboard and the short trip to work or gas station etc. I’m pretty confident in my printed parts for this use. Just need to nail down these brakes/belt issue.
@b264 while we were discussing the orientation of the idler regarding forward or rear mounting, and I referenced the other forum thread, now I think about it I don’t recall if those people were using this to combat slipping during hard acceleration or braking, depending on which case would dictate the idler position.
Confirmed belt slip on hard brakes, tried flipping the idler to the other side, still slipping. Slipping on the motor pulley for sure, printed wheel pulley seems fine. Next step wider belt or dual idlers or both.
On the other side I still have not played with the esc settings. I can basically roll down the driveway while holding the brake, so something is not right. I can slow down pretty good but that last 5% brake is just not there. I’ll mess with the settings this afternoon.
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Could you check if your grub screw is fully inserted on the motor pulley?
Did twice. It’s locked in.
I’ll fix the slipping for sure, just puzzled by not having super low speed brakes. I’ll try to post a video. If I was on a hill, I’d roll right down for sure. And it’s not slippage for this part.
This is bugging me. Can you post another pic on your setup. Including the printed wheel pulley?
I’m almost sure you will only solve that by getting rid of the 3D printed mount, or going with a way larger motor pulley
I had even 6 mm 6061 mount bend when using in a single drive
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I’ll keep it in mind, this mount seems to fit just right so I’ll progress towards having my friend make me one on his cnc router. But I think with the wider belt and two idlers, it would work just fine.
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Super low speed brakes don’t work, it’s the nature of how BLDC motors work. You’d have to apply power to slow down further instead of charging the battery.
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