Yes i could reproduce this on all 4 units.
Right now i use the newest firmware: 3.57
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@doomy myself and others have had trouble with the newest firmware on the Cheap FOCer. I highly recommend downgrading to 3.4x or possibly even using Ackmaniac’s firmware for 4.12 hardware.
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The issue is the automatic setup wizards?
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Partly. The motor also ran extremely rough in FOC mode with the 3.57 firmware. A beta tester also had issues with a slightly earlier version of 3.5
Yes that was it, resoldered R34 and voltage reading is good now… all 4 of the FOCers working now 
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Wonderful! Keep it up! I want to see spinning motors
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Finally made a new account here since it seems most of the discussion on this Vesc design is here.
My boards and components will be here in a few days 
@doomy So do you know what caused the DRV series resistor to keep blowing initially?
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The GND pad was not properly connected. I just used flux and my TS100 soldering iron from the back of the board. This was not enough on all 4 boards!
I recommend to lightly pretin the chip pad and the board, then apply flux, solder all the pins and then make the GND connection with alot of heat and solder from the back. I used my 100w soldering iron. You can check with a multimeter when the connection is made.
A few tips for the build:
- Start soldering the MCU and DRV, then the crystal, then from smallest to the biggest components
- Use lots of flux and very little solder (most importantly for MCU and DRV, they were surprinsingly easy to solder)
- Be carefull when soldering the silicone wires, at first i did not pretin them and a few single wires were sticking out. This can easily destroy some nearby components
- Build all the boards in parallel or if you are not sure start with one, test and then build the rest together, its alot quicker like this.
- Use good solder wire (i have Felder 1mm Sn60 Pb40 its a bit too thick would prefer <0.5mm)
- Use Non corrosive flux (i made my own with Rosin and alcohol)
- Print the BOM and cross out the soldered components
- Do a good visual inspection before connecting anything, check for shorts on and between power rails (VIN, 5V, 3.3V)
- Test first with a current limited power supply
- Post some pictures and results
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I was thinking of soldering two corners of the drv to hold it in place then going for the ground, that way I could try to lift the drv slightly and if it does not move then I know the ground has been successful soldered, then carry on to the rest.
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Here you go:
@Alpacaslapper
That sound like a good idea. Just be carefull that you dont bend the pins, they are tiny.
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Beautiful! Great job getting those working! I’m glad to see someone successfully put these together the way I had envisioned. Starting with the files on the GitHub repository and ending up with functioning low-cost motor controllers.
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With the vias (holes) the drv gnd will be the easiest part
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As soon as those V1.0 files are uploaded i’ll be ordering some pcb’s, can’t wait
Edit: couldn’t wait and ordered some from JLPCB because there so cheap.
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So we saw that R48 blew out during @doomy’s attempts to power up the FOCer when the ground pad wasn’t properly soldered. This of course means that R48 would have to be replaced or bypassed to get power to the DRV again. There is a device called a PTC fuse that would trip, increase dramatically in resistance, choke current down to safe levels, and reset itself after power is cut off.
A PTC fuse like the one linked below could be a drop-in replacement for R48 of which would be better for protecting the DRV in over-current events. I may even make this an official change for the v1.0 release. It could help mitigate the issue of burning out DRVs because of improper soldering or anything that could cause an over-current event.
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Where do you guys buy your components? I’m in Canada and usually order from AliExpress as it’s cheap and I’m not getting f* on shipping. But sometimes it lacks choice. So I was wondering if there are other good options?
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LCSC. Cheap components and you used to be able to bundle your shipment with PCBs from JLCPCB. Idk if they still do the bundle though.
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No bundles anymore. But you could get a shipping discount if you created your account when they still did the bundles. Anyway you get a first order discount if you use the link from jlcpcb.
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Nice! Thanks guys
Just someting that came to my mind when ordering parts for my A200s build:
Why no use a microUSB instead of a miniUSB on the cheap FOCer?
You get 5 connectors for 0.46$ instead of 1 for 1.23$
Plus microusb is used alot more than mini so you always have a cable.
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