Mellow Micro4 DIN Rail Mount with 50mm Fan Mount

Mellow Micro4 DIN Rail Mount (LOW PROFILE!!)

I needed a DIN rail mount for the Mellow Micro4 board, and wanted it as low profile as possible to safely mount a fan over the top.

While there are a couple of models available online, they aren't a complete package, and there are no contingencies for mounting a fan.

Sadly, they weren't suitable for my needs, so queue a cup of coffee and 30 minutes in CAD!

ABOUT THE DESIGN...

Mounting clips are inspired by "DIN Rail Bracket" by Fabian (model no longer on printables), included in the Voron 2.4 stl pack.

"DIN_Mount_BASE"

• Mounting holes are 4.5mm dia with a chamfer on the side meeting the build plate - suitable for M3 heat inserts.

"Standoff"

• Gives approximately 3mm of clearance between the mount and PCB for solder joints.

"50mm_Fan_Mount"

• Mounting posts are apprx. 22mm in length

• Fan mounting holes are 4.8mm dia

• After printing, the fan mounting base is a little flimsy - please handle with caution until your fan is bolted into place. FIXED IN v2.

BOM

With Fan:

• 4x M3x35mm screws (button head for a clean finish)

• 4x M3 heat insert (3x5x4mm) / 4x M3 nuts

• 4x M4x15mm screws

• 4x M4 nuts

• 50x50x10mm fan (voltage matched to your printer)

Without Fan:

• 4x M3x12mm screws

• 4x M3 heat insert (3x5x4mm) / 4x M3 nuts

PRINT SETTINGS

• Filament: ABS

• Temp: 265c

• Perimeters: 4

• Infill: 0%

• Supports: No

• Raft: No

• Brim: No

• Layer Height: 0.2mm

• Nozzle: 0.4mm

Print time: 30 minutes apprx.

All .stl files are print ready, just drop them into your slicer, pick your filament profile and send it to your printer.

If printing in ABS I suggest to scale this between 100.69-102.5% depending on your printers tolerances, accounting for shrinkage.

As seems to be the standard these days, I will suggest 40% infill, 4 perimeters as per Voron build specs, but honestly to save a bit of time on prototyping - I went with 0% infill and they're fine - the parts are so small that the perimeters give all the strength.

SUMMARY

Although I'm happy with this model, and it more than fits the purpose, it could do with having the fan mount thickened, and possibly the base to make the heat inserts sit flush with the plastic - I may look to do these over the next few days once I've caught up on my current build. v2 uploaded 18th April 2026.

Happy printing, don't forget to post a make if you use it!! 

v2 ADDED 18th APRIL 2026!!

• Increased thickness of 50mm fan mount base to 2mm

• Increased thickness of Micro4 Mount Base to 4mm

• Removed redundant files