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View attachment 673246
Those are 2 90mm 1k rpm fans (practically cant hear em) wired in parallel in a push/pull configuration of this old server cpu heatsink (7bucks a pop). I already soldered the cobs, tinned the wires and closed the series with the driver for testing, now I'm soldering the fans together (sans the rpm cable). Tomorrow the milled bottom plates should come in then I can mount the cobs(green) on the copper plate (the star looking one) and sandwich them from the front with the steel plate (red)(which has a hole in it for the light)
Building 4 of these for my tent which will more than double the light my lovelies get. That should give Jack a good kick in the pants for the flowering