Rasperry Pi 4 NAS for 4 HDDs

thingiverse

This is work based on xxdavexx's excellent design for a Raspberry Pi-based NAS. Since that design was specifically targeted toward SSDs, I refactored it to instead support HDDs, which, at this time, still provide a much higher density (size) for lower costs. In my design, the following changes have been made: * The Raspberry Pi enclosure has been extended by about 1/4" to provide better passive airflow for the v4 board. * I scaled up the drive cage to snugly hold 2.5" HDDs, which are two or three millimeters taller than SSDs. * I reworked the original power supply enclosure to instead provide an enclosure for a USB 3.0 Hub (because my electrical skills are not as good as his, and I was terrified of frying components). * The drive enclosure has been split in two so it can be printed without supports. My components are connected together using super glue (Loctite), but I'm thinking of updating the design to use a dowel-based system so parts fit together without adhesive or solvents, allowing for quick and easy tear-downs - e.g., components can be quickly replaced if necessary. I tested the array in a dual 2TB RAID0, and I got 96MB/s throughput on my gigabit network transferring a file to one of the drive arrays. That's pretty respectable, given four USB 3.0 channels from the hub are funneling into the Pi using only one of its USB 3.0 ports. xxdavexx's original system used a Raspberry Pi 3, so it was limited by the lower-throughput USB 2.0 ports. All told, my power measurements show this system uses 10 watts (16 VA) at idle. BOM: * Raspberry Pi 4 2GB Model B[1] * USB 3.0-to-SATA adapter[2] * 4-port USB 3.0 powered hub[3] [1] https://www.amazon.com/Raspberry-Model-2019-Quad-Bluetooth/dp/B07TD42S27/ref=sr_1_3?keywords=raspberry+pi+4+model+b+2gb&qid=1579809714&sr=8-3 [2] https://www.amazon.com/gp/product/B011M8YACM/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 [3] https://www.amazon.com/gp/product/B07VSD52J6/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1