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https://www.mcmaster.com/94180A363/
Tips
I forget which page I read this on, but there’s a
Installation Video
Follow this video for installing the heat set inserts into 3D printed plastic parts.
Do not use any force when installing it, just let the weight of the soldering iron push it in.
Also, be sure to use the soldering iron vertical rail jig in the bay with the special tip to install the heat set inserts (https://www.adafruit.com/product/4239), there is one in the bay.
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