Modular ITX/DTX/mATX/ATX/EATX/SSI-EEB/SSI-CEB/XL-ATX mainboard frame/tray

A simple modular PC mainboard frame/tray system intended for open-air or custom enclosure PC builds.

Version log:

• v1.1 initial design concept
• v1.2 SSI mounting holes, recessed landing pads for frame mounting screws, legible part name inscriptions
• v1.3 matx updated to be 4 pieces to print on smaller printers
• v2 all standoff holes same size, added missing standoff hole on atx2, add 0.25mm filets to all edges
• v3 re-uploaded files with “medium” detail level to be <1MB each; matx1 piece adds a protrusion for an optional standoff location; itx and atx pieces add optional standoff locations for SSI style mainboards

Required parts:

• mini-ITX/mini-DTX
  • 1 print (itx.stl)
  • 4 motherboard standoffs
  • 4 screws to secure the frame
• DTX
  • 2 prints (itx.stl & dtx.stl)
  • 2 nuts/bolts + 4 washers to fasten parts together
  • 4-6 motherboard standoffs
  • 4 screws
• micro-ATX
  • 4 prints (itx.stl, dtx.stl, matx1.stl, matx2.stl)
  • 4 nuts/bolts + 8 washers to fasten parts together
  • 5-8 motherboard standoffs
  • 4 screws
• ATX
  • 4 prints (itx.stl & dtx.stl, atx1.stl, atx2.stl)
  • 5 nuts/bolts + 10 washers to fasten parts together
  • 6-10 motherboard standoffs
  • 4 screws
• EATX (SSI-CEB/SSI-EEB/XL-ATX)
  • 6 prints (itx.stl & dtx.stl, atx1.stl, atx2.stl, eatx1.stl, eatx2.stl)
  • 7 nuts/bolts + 14 washers to fasten parts together
  • 8-15 motherboard standoffs
  • 4 screws

Exterior measurements of the parts:

• itx: 170.330mm x 171.600mm
• dtx: 170.330 x 72.240
• matx1: 171.6 x 45.720
• matx2: 72.240 x 45.720
• atx1: 134.470 x 171.600
• atx2: 134.470 x 45.720
• eatx1: 134.470 x 86.360
• eatx2: 170.330 x 86.360

Notes:

• Accepts 6-32 and M3 motherboard standoffs. Holes are 3.25mm in diameter gradually tapering to ~2.3mm to grip the standoffs. This may be adjusted in future revisions.
• Extra holes are added to accommodate SSI-style boards in addition to ATX style boards
• 10mm z-height - combined with ~6.4mm motherboard standoffs provides ample clearance for PCI card tabs
• Can use a variety of fasteners to attach the frame parts together for ATX/EATX and/or secure the frame to a surface or custom chassis. Fasteners can be up to ~4mm in diameter. Washers should be used to spread the load against the plastic.
• PETG recommended for durability/flexibility, but PLA is OK. For environments where air temperature exceeds 60°C, ABS/ASA is probably a better long-term material.
• Most 3D-printed materials are non-conductive and can build-up static charge. I doubt its necessary, but to mitigate static, insulated ~28awg wires terminated with spade connectors can be run between a few motherboard standoffs and then grounded to the power supply. 

References for motherboard sizes and standoff locations:

• https://web.archive.org/web/20160817033942/http://www.formfactors.org/developer/specs/atx2_1.pdf
• https://www.snia.org/sites/default/files/SSIF/2018-05-31/SSI%20EEB%202011%201.0.1.pdf
• https://digitallibrary.intel.com/content/dam/ccl/public/600565-btx-specification-update-rev1p1.pdf
• https://linustechtips.com/main/topic/812415-ee-atx-standoff-locations/ 
• https://www.gamersnexus.net/guides/3566-e-atx-is-a-lie-vs-xl-atx-eeb-ceb
• https://en.wikipedia.org/wiki/ATX#Variants
• https://hardwarecanucks.com/forum/threads/lets-go-team.12383/page-432#post-527475
• https://www.silverstonetek.com/it/tech-talk/wh11_008 

To-do:

• Check standoff spacings for SuperMicro EE-ATX/SWTX, and SSI-MEB
• Design add-on parts to hold a clip-on I/O shield and PCIe cards in place.