New server front panels

New server front panels

My home server and backup server run in two Inter-Tech 40240 19″ rack-mount cases. In 4U and less then 500mm depth, they fit 11 HDDs and can easily be modified to fit many more. Since the case is relatively cheap, it is ideal for a basic home lab. Without external hot-swappable drive caddies at the front and the three 5.25″ drive slots, it looks a bit boring, though. For a long time, I wanted to try out laser cutting and sheet metal fabrication, so new server front panels are a great project.

The goals for this project were to experiment with laser cutting, sheet metal bending and to achieve a good (enough) design. The I/O panel with USB ports, LEDs and switches should be reused and the design had to allow for good airflow to the intake fans cooling the drives. A further requirement was to clearly label both servers.

Luckily, Fusion 360 has a sheet metal fabrication mode that deals with bending sheet goods. After construction, Fusion 360 allows to unfold the design into a flat shape to be sent to a machine or manufacturer for cutting. After testing various ideas, I came up with a honey comb design and the server name in larger monospaced letters (remember to add tabs to non-contiguous letters). To keep it simple, only the top and bottom edges are bent 90 degrees and screwed to the case. The original front panels also have bent and screwed sides but those seem unnecessary to me.

I did not know how well the bends would work, i.e. how tight a bent I could achieve, so I did not include screw holes in the 3D model and instead drilled them after bending. The I/O panel is attached from the backside with hot glue to forgo visible screw holes in the front.

Today, there are a large number of manufactoring companies that print, route or laser projects in small quantities for relatively cheap. I went with a local provider and sent them the exported flat dxf plan. I went with stainless steel and the same thickness of 1.0mm as the original powder-coated front panels. Despite the large size and expensive materials, each panel was only about 30€. The raw product arrived a short while later like this (further processing by the manufacturer is possible and actually not too expensive). Even the very fine holes were cut nicely and little burned up dirt stuck to the underside.

The new front panels how they arrived by mail, prior to any processing steps.

In case you want to create your own front panels, here are my final files:

After deburring and cleaning, the sheets can be bent with bending jaws in a vice. The flexible sheets gain a surprising amount of stiffness in the process. With the short 100mm bending jaws that I have, the panels warped slightly while bending but this can be remedied by further strategic bends. Special care was taken to bend in the right location as the panel has to fit in the server case later which allows for only 0.5mm deviation. Overall, this went surprisingly smoothly and makes me want to build more sheet metal cases for future projects. The final step is to drill holes to attach the panels to the case. I designed the bent flaps long enough to have the new front panels sit 5mm further out than the old ones. This should increase the efficiency of the intake fans and improve airflow.

The server rack is in a closet under the roof and shares its room with the 3D printer. The old systems on top of the rack found a new home in the 19″ cases with custom front panels.

From top to bottom, the rack houses: FritzBox (DSL modem and router), cable brush, 16-port switch, home server (Inter-Tech 4U 40240), backup server (Inter-Tech 4U 40240), PDU (power distribution unit) with separate fuses for each outlet and 500VA UPS (uninteruptable power supply).

The 3D printer to the right is a modded Ender 3 V2 controlled by OctoPi running on a built-in Raspberry Pi 3. The orange box houses a camera for monitoring and timelapses (Camera Mount on Thingiverse).

Overall, building new front panels was a nice visual imrpovement of my rack and helped me learn a lot in the process. Laser cutting and sheet metal bending will probably become my go-to methods for robust projects and intricate cutouts in the future.