Tired of the summer causing my extruder to overheat and jam I decided to find a solution. I did with a peltier, or thermoelectric cooling (TEC), device. Result: mediocre. Could be useful in special circumstances but is easily overcome if the peltier heatsink is not sufficient.
Fed up with inadequate cooling I decided to change things. Here I added a thermoelectric cooler in place of the 40mm fan. It's also completely silent!
I used a PSU from an old 3D printer.
A peltier device AKA thermoelectric cooler. A few dollars on eBay.
Any heat sink that will fit in your machine. It helps maximize the cooling ability of the TEC.
Grease or glue. Depends on your situation.
Make sure you get everything that you need to mod your extruder. Measure everything, check the spacing and clearance of parts, and be ready to get creative.
Order what you need, use what you can
I got most parts from scrap: heat sink from a discarded and very out of date PC graphic card, wiring from old power cables, 12v PSU from an old printer, etc. I had to order the 12V 40x40mm TECs and those took a while, free shipping on e-bay. I also picked up thermal cement (glue). In my case the heat sink was going to be heavy and I was, likely, going to have only one screw to use as anchor. The glue works like thermal grease but adds support I would, and did, need.
Test parts and fit
The heat sink had to be cut to size. Just chopped it up with a hacksaw and Dremel cutting wheel.
I used a broken fan to align the holes to be drilled.
It took a few tries to get the heat sink to clear everything. There was a metal bracket on the print head I hadn't accounted for. I was test fitting on the print head bracket and discovered my mistake.
Do a test run of the peltier to:
1. Make sure which side is hot and which is cold. For me the labeled side was cold.
2. That it worked properly. They're cheap, ceramic, and ship from China in bubble wrap.