Add RD6006P 18650 battery holder

README.adoc

@@ -4,6 +4,19 @@ Solvespace models
 This is a collection of my custom-made 3D models intended for 3D printing,
 with some commentary.  Solvespace 3.0 or newer is required.
 
+18650 battery charger
+---------------------
+The RD6006P laboratory power supply can charge li-ion batteries, but you have to
+make your own battery holder.  I've made it so that the thermocouple merely sits
+in a trench underneath, and the battery needs to be pressed down against it.
+
+image::18650-battery-charger.jpg[18650 battery charger]
+
+Antenna connector cover
+-----------------------
+Just a one-off box to prevent cables from getting entangled upon adjusting
+the height of my desk.
+
 Bathtub strainer
 ----------------
 The first thing I've ever modelled for printing, hence the simple geometry.