My original tinyG is a V7, which had good clearance for drilling holes to which I attached a junkbox AMD CPU heatsink via a locally fabricated interface. I sort of prefer heat sinks over fans, but have found over time that a 80 or 90mm fan blowing directly up onto the bottom of tinyG keeps the drivers quite happy (thermally), is quiet and accommodates different versions.
The driver devices are in heat slug packages that are well connected (thermally) to the bottom ground plane. I believe they dropped the smallish top mount heat sinks as they did not significantly affect dissipation capability.
Many folks have built custom enclosures for electronic and connectors, almost all of which have one or more fans.
The design target for tinyG was initially relatively lite weight NEMA17 machines that did not demand super torque. If I were retrofitting a Bridgeport with honking big NEMA23’s or 32’s, I would probably look seriously at external drivers (after retrofitting my workshop with a 12″ concrete floor 🙂 ). There are of course an infinite set of possibilities in between.
An inexpensive laser guided thermal gun can be your friend here; monitor your board(drivers) while it is running to evaluate the adequacy of your implementation.
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