Is there anything you can’t do?
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Anything very quickly…
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All in good time my wizard.
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FOCer sammich. Shows the way I mounted the FOCer to the heatsink. M3 screws, 4.5mm 3D printed spacers, and 0.5mm silicone thermal pad.
Auxiliary 5V for fan goodness. Yes the connectors on the PCB are burnt/melted (don’t ask). You can also see the springy thing I made and soldered to the PCB for low-inductance measurements of the switching waveforms I posted earlier.
50mm 5V fan and aluminum heatsink from AliExpress. Fan mounts with M3 screws with screws self-threading between heatsink fins just right.
Ok so now I finally mounted a heatsink to this thing and collected some thermal data. It was a crude test but the numbers seem decent
20A FOC with fan
Start 20C. Leveled off at 28C
20A FOC without fan
Start 25C. Increased to and leveled off at 38C in 10 minutes. Stopped cause I got bored
50A FOC without fan
25C to 50C 2 minutes. Stopped cause motor was getting hot
50A FOC with fan
25 to 49C in 3 minutes. Creeping at 0.1C per 5s. stopped cause motor got hot
Ambient temp was about 20C. This isn’t professional data but its something for now. I’d say the heatsink and fan do a decent job.
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That’s some good numbers!
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Looking forward to these, I suspect that maybe using thermal epoxy vs a silicon pad may provide better results. Then again its been ages since i looked at the thermal coefficient of really anything so that just might be some old anecdotal theory creeping up.
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The silicone thermal pad is necessary to also electrically insulate the MOSFET tabs from the heat sink.
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Any thoughts on moving or having the capacity to utilize SMD FETS? I’m genuinely curious if it would make much difference in the grand scheme of things.
Also - these are already looking solid enough that I may use them on my DWII board until the Serious FOCer is out 
I would say the only bummer I can think of here is that 13s may still be out of reach on this design.
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I’ve thought about it 
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Probably where I got the idea to be honest 
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Shaman your are my hero 
! Really admire al the effort you are putting into this.
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YESSSSSSSS!
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You know my opinion
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Cool. 
It would be good to have a silk screen boarder around these components so its easy to identify if you have IMU functionality or not.
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Yes. 
Although I would put the IMU txt inside the box just above R70r69 txt in the same vertical orientation.
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Fab shop:
Did he design this for fucken weetards?
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I think u miss a red arrow man
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