@shaman thank you for all your help in getting yhe the pcbs and components right (hopefully).
Just got these in the mail. The fets have been delayed due to…you know what…but looking absolutely gorgeous.
Heres some pics and size comparison with the vesc 4 aka expensive focer.
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The repo has been getting reviewed and adjusted this past weekend by a few volunteers from this community of who I’ll give credit to after release and after I have their permission.
It’s really starting to look good btw…
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Question space-wise.
Is that kind of standard from JLCPCB, because it looks like you could shrink it down a lot and safe some space?
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The PCB is 2-layer w/ all the SMD components on one side. This ultimately causes the PCB to be the size it is. The VESC 4 is 4-layer and double sided which allows for the size to shrink but this is much more expensive. The absolute smallest I could get the CFOC2 PCB is about 50mm x 100mm. Of course you’re more than welcome to try and shrink it down yourself after I release the design files.
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Ahhhhlright, i see 
I´m not an PCB expert, so others should see what they can get out of it, but i think you did an awesome job sofar!
I´ll see if i can build a few for some cheaper builds later on.
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Yeah the whole 2-layer and mostly single sided design decision is to facilitate low-cost and to maximize assembly from JLCPCB.
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My corrected part placement looks ok, but it looked ok to me before it was corrected too lol! The only incorrect thing i noticed was the DRV lol!
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Cool. Yeah JLCPCB is good about correcting part placement in their “DFM review”.
FYI @NuRxG is one of those reviewing and improving the GitHub repo and documentation. Going through the ordering process is part of the review
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whops, posted it in the wrong place 
I feel like such a boomer now.
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If you start feeling sick with flu like symptoms, then you can start feeling like a boomer. Otherwise you’re fine.
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I’ve been slowly teaching myself to assemble electronics. I don’t have time or reason to add building one of these to my project list. but I keep being drawn to this project.
@shaman this is so cool what you’ve done for the community.
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Alrighty, I’m gonna ask maybe the dumbest question I’ve asked yet…
As I understand, the VESC design is sort of notorious for self-destructing when running in FOC mode. Given that these new designs have FOC in their name, is it fair to assume they’ll be more reliable in FOC mode? And I might as well ask - why is FOC harder on the controller?
Very sorry if this has been covered in the thread. I have in fact read every word of the thread, but it’s been a while, and I’m old and doddery. 
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FOC is harder than BLDC because you have to switch your MOSFETs ON/OFF a lot more in FOC to achieve / emulate a sinusoïdal signal through your motor (smoother, silent and more efficient and supposedly more torque but less top end).
In BLDC you send a “blocks” on/off like signal to your motor so FETs switch a lot less. That’s brutal so you have noise and less smoothness but feel a bigger torque somehow and have more top end too.
Recent VESC don’t have problem with FOC as long as you keep amperage and voltage reasonably down. It’s overcurrent and voltage spikes which kill them, not FOC per se.
Hope this helps.
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totally forgot that…so i can reach 56km/h in foc with a bit play left…how much could i achieve with bldc then 
edit: with top end you mean speed or “power output” the force you can feel?
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Yes top speed 
maybe you can top 60km/h in bldc
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The VESC uses space vector modulation when in FOC mode. This does indeed have a more complicated switching pattern for the MOSFETs like @Vanarian mentioned. This complicated switching pattern combined with high currents, running the VESC close to its abs max, and hard braking can put a lot of stress on that little DRV.
What I’ve done with the CFOC2 is designed in some more traditional gate drive tricks such as snubbers that help squash voltage spikes during all of that MOSFET switching in FOC mode.
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I’m confused. I thought just above you were saying FOC provided more torque but less RPM(?)
Key words are “supposedly” and “feel”, you feel more punch in BLDC because control is less granular and at top end the extra vibrations of coil somehow act like a hammer at top speed giving a extra Oomph.
In theory however FOC is more efficient and should give you the optimal torque from your motor. At the same time you don’t have the extra Oomph from the coils vibrating at high speed.
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Now I’m even more eager to build one (or more) of these bad boys so I can try FOC mode!
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@ziploc What voltage do you plan to run at?
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