@Lou N posted:
My experience was the exact opposite. The application was high power IR diode lasers for a medical product. My choices for heat sinks were: copper base with graphite fins, all aluminum heat sink, and aluminum base with copper fins. The aluminum base with copper fins was the best choice [for this application]. Please note that the heat sink grease was silver filled and a high speed ducted fan cooled the fins. Lasers have the nasty habit of thermal runaway when they reach 80~85C. At a grand a copy I had to get it right.
If you have an interest in copper heat sinks just Google: Cool Innovations Thermal Systems.
To circle back to the original intent of the question: yes small heat sinks will help and they can be attached using at least two different ways mentioned in this thread.
Lou, I think your experience leads me to the conclusion that I was not taxing either the copper or the aluminum sink to the point that it mattered. Which may be the case in most of our toy train exploits. I do have some experience using liquid cooling with a copper radiator on a gaming computer I built several years ago. My nephew returned the box when it became obsolete for gaming and I am using it for streaming 4k video now. Think I used Thermal Grizzly compound on the processor. That box always runs cool. "Cool Innovations" Them some really purdy copper sinks. Always amazes me how beautiful technology can be. j