PoE Hat Compatible Pi Cart/Sled

thingiverse

This is my first Thingiverse upload, so be gentle :) This is a drastically tweaked cart/sled for [the 2U Raspberry Pi Blade Server](https://www.thingiverse.com/thing:1606631) to accommodate PoE hats. Specifically tested models are: --- * [The official Raspberry Pi PoE+ Hat](https://www.raspberrypi.org/products/poe-plus-hat/) (there is a difference between PoE and PoE+ models although both should be fine, only the PoE+ version was tested) * [UCTRONICS PoE Hat](https://www.amazon.com/gp/product/B082ZJYCS3/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) (Amazon link, NOT an affiliate link) Major adjustments include: --- * Widened the sled as it was too narrow and would often fall over in the vanilla "cage" * Reduction in the height of the base * Due to the reduction in height of the base, the front lip (where the label would go) had to be eliminated due to it obstructing Ethernet and USB ports. The original lip wasn't tall enough to fit a standard sized label anyway * Countersunk screw holes so you can come from underneath the board, through the board, and into the standoff that comes with the PoE hats * Hex standoff prevents the solder points from digging in to the sled or possibly damaging either the Pi or the sled with various protrusions underneath the board. This will vary from board to board as the tolerances will vary a bit. In my 15 carts, I'd say 4-5 were warped a bit due to this but they still fit fine in the outer "cage" **One major thing to note that you'll likely notice when you go to slice is that the only material joining the countersunk screwhole with the hex standoff is a filet. That filet is very important as a result. Unfortunately, the PoE hats have fans and those fans add height; one of my fans had screws protruding out the top by as much as 6mm and I really didn't want to grind these down. This is literally the shortest the sled can get and still be held together. Keep in mind, these just hold Raspberry Pis in their cages, they don't need to be beefy, just rigid and as little warp as possible** I would recommend picking up [at least one of these screw kits](https://www.amazon.com/gp/product/B07CLQFQ4C/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1) (Amazon non-affiliate link). You will need 8mm long screws to come in from the bottom to go into the PoE hat standoffs for the official PoE hat; the included screws are not long enough. I was able to repurpose some of the included screws on the UCTRONICS model if that helps, otherwise, it never hurts to have extra M2.5 screws, nuts, standoffs, etc. laying around if you're working with Raspberry Pis Due to these PoE hats having fans that will direct heat from the hat and Pi CPU to the board next to it, I also designed 80mm fan brackets for the 2U rig which I'll post later along with a control box bracket to control the speed of those fans. I'll put a link here when it's posted. Print it oriented with the bottom facing the bed. For some reason, Fusion 360 always exports STLs sideways so make sure you rotate. Something handy to have to punch out the screw holes is a 3/32" hole punch, worked like a champ!