4 State QRP Group Dummy Load case

thingiverse

This may still be a work in progress, but I do consider it mostly finished. Case for the Four State QRP Group's new QRP dummy load kit. The four corner spacers should be tapped either 3mm or 4-40 depending on whether or not you use metric or SAE screws. You will need 8 either 3mm by 6mm or 4-40 by 3/8" screws. Mount the Printed circuit board to the case bottom using 4 of the screws and the 4 corner spacers which will hold the PCB down and provide mounting for the top cover using the remaining 4 screws. The 4 "Light pipes" are designed to fit through the holes in the (Lpipe mount) and subsequently through the 4 labeled LED holes in the top cover (Lid). You could also mount the LED's above the PDB far enough for them to protrude slightly through the holes in the lid and thus avoid printing the light pipes & their mount. In my opinion though, this could, over time, cause the LED's leads to get bent or damaged and that's the reason I designed the light pipes. Due to the tight tolerances on the holes, the light pipes should be printed with the larger diameter part (that fits over the LED's) down to the printing bed as it's almost impossible to eliminate all ("Elephant's Foot) and the smaller diameter part of the Light Pipe would not fit through the hole as it should. The "LID" or top cover should be printed with the text & 4SQRP Logo up and if you like, the lettering/Logo can be printed in another color from the base of the lid. The lid itself is 2 mm thick and if, like I do, print with 2mm per layer, change filament color at the beginning of "Layer 11" or at the equivalent beginning of the 3mm layer. The "Light Pipes" MUST be printed in either "Natural" or "Transparent" filament. It was suggested to make the cover white as the light from the LED's would show through. This doesn't work as the LED's do not glow bright enough to penetrate the White PLA well and also the lettering on the PC board indication the power output for each LED would not be visible. That's why the holes in the lid and the text labels for each one. Since I used Autodesk's Fusion360 to design this, I have included my .f3d files as well so you can edit the design to suit yourself, but if you do I would appreciate it if you would at least acknowledge my original work and I am licensing it as NON COMMERCIAL so you may NOT print this case for sale without my express permission. You may, however charge for your time and materials if you print one for another individual who doesn't have a 3D printer.