Youmile LM2596S DC-DC Buck Converter case for 1, 2, 3 or 4 converters

thingiverse

# Youmile LM2596S buck convert(s) case Case that can hold between one and four Youmile LM2596S DC-DC Buck Converters, using standard 3 pin PC fan power connectors for power pass through and v-slot rail on the bottom for universal mounting options. The button allows you to verify the input and output power. On the inside of the top cap there is a sketch of where the adjustment screw is located, if you want to have direct access to this screw you can use this as drill guide. The side has holders for a male and female 3 pin fan connectors. I used Noctua cables for my reference models, but since it appears to be a standard 3 pin fan connector, it might also work with other brands. No glueing is required as the connectors will stay in place using friction, although they might slide out when you try to unplug them. The included mounting bracked was designed for an Ender 3 V2 printer, which uses 4040 double slot v slot extrusion profile and should be compatible with printers using similar profile. The only thing I did not model myself was the “T-nut M3 drop-in rotating V-Slot”, which you need to screw the bracket on the 3D printer and the buck case on the bracket, so you need to find a model for this yourself. I created a model in which the amount of buck converters is a parameter, this allows me to change the buck converter count with minimal effort. Do note however, that I only printed and tested the 4 converter housing. Please let me know if I overlooked anything and you run into any problems using the 1, 2 or 3 model variants! The nut and bolts required are M3. The nut that I used are 2.2mm thick. The bolts have a hex head that is 3mm thick and 5.3mm in diameter. I just bought an assortment box with all M3 bolt sizes and picked whatever worked, but here are the lengths of the bolts, based on the 3D model measurements: For each buck converter: - 4x M3 15mm bolt - 4x M3 nut For the case: - 4x M3 anything between 22 and 26 mm should work - 4x M3 nut For two mounting brackets: - 8x M3 bolts (not sure about this length) - 8x M3 nut - 8x 3D print of T-nut M3 drop-in rotating V-Slot (Not included, I just downloaded this elsewhere) On the side of the case legs there is an opening in which you can insert a nut. Because this opening is big, the nut will rotate freely when you try to screw the bolt in. To fix this, I inserted the nut in the leg, then screwed a bolt in the nut (pushing something against the nut to prevent it from rotating) and when the bolt was entirely through the nut I hot glued the nut in place. Then unscrewed the bolt again, attached the bottom and finally screwed it back in. ## Ender 3V 2 printing settings: I used the cura standard quality profile and used a 0.4mm nozzle. I did reduce retraction count from 100 to 20, because the tiny honeycomb cooling on the top case made the extruder retract so often that it flattened the filament to the point where it started to get stuck in the bowden tube, the filament started grinding and broke. It could be that this was only a problem on my 3D printer, because the extruder tension is too tight. But the screw for pre-tentioning the spring is already entirely unscrewed so I cannot reduce it any further on my printer. ## Reference models You should not print any of the reference models, I only included them for when you want to make modifications to the case model or if you want to use them for your own constructions. ### The reference models Buck converer, contains the most important compent shapes that were required as reference in the case 3D model Noctua connectors. Basically 3 pin male and female power connectors as referenced for creating the holders. Noctua connectors outline. As the connector, but then outline (without pin/cutout) which you can use in boolean operations when creating your own on holder. In my model I post applied an extra 0.2mm offset, since an exact cutout would be too tight. Noctua connector holders. These are ready to use holders that you can attach to your 3D models. They already have the 0.2mm free play applied and printing them should allow you to insert your connectors. Double slot v slot extrusion profile shape reference model as used on my Ender 3 V2