A dehumidifier for your 3D printing dry box to keep your filament dry without the need for desiccant.

Overview
After building this project you should have a fully functioning dehumidifier for your 3D printer dry box to keep your filament dry and ready to use. The dehumidifier works using a Peltier device which transfers heat from one side of the device to the other producing a hot and cold side. The cold side of the device produces condensation thereby removing moisture from the air within the dry box. The Peltier is sandwiched between two heat sinks in which a fan blows across. The fan provides cooling for the hot side of the Peltier while also blowing off built up condensation on the fins of the cold heat sink. The dehumidifier is controlled by two Particle Photons. One Photon controls the Peltier device while the other reads the humidity and temperature inside the dry box. The two photons communicate with one another to determine whether the Peltier should be on or off and whether the power level should be set to one or two (low or high). The high power mode kicks in when the humidity level has reached approximately 30%. At this point further moisture can only be removed from the air by going below freezing. The desired target humidity and other parameters can be set at the top of the code using the predefined variables.

Assembly
First, cut the original barrel plug off of the power supply and solder on the new high current barrel plug.

Assemble the two heat sinks and the Peltier module using thermal paste and the clamp bracket. Attach the clamp bracket using the fasteners included with the large heat sink. Make sure to orient the large heatsink with the fins running in the long direction of the clamp as shown in the picture. Otherwise the heatsink will not fit into the enclosure correctly. Note: The springs included with the heatsink will not be used for this project.”

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