2023-02-11 - EE Hardware Mounting Hole Specification

Owned by Daniel Puratich, created
Last updated: 2023-02-16
2 min read

Change Description

Custom EE Hardware

Mounting Hole Specification

Daniel P

DanielPuratich#7941

Description of Change

For general custom EE flight PCBAs going forward we will follow this mechanical mounting hole specification:

M3 - Any PCBA with area exceeding 2500 mm^2

3.400mm hole diameter (0.1mm tolerance)

6.000mm annular ring diameter

M2 - Any PCBA with area exceeding 750mm^2 and less than 2500mm^2

2.400mm hole diameter (0.1mm tolerance)

4.200mm annular ring diameter

No Mounting Holes - Any PCBA with area less than 750mm^2

No mounting holes will be present on board of this size.

All Mounting Holes will follow:

electrically not connected to the PCBA (frame is ideally floating potential)

Eight vias (plated drills) placed evenly in the annular ring (in whichever drill size is used on the board (so effectively left to EE in charge to decide on via size)) for mechanical stiffness.

Electrical component soldering pads should be at least 1mm away from the annular ring to avoid damaging the PCBA when mechanically bolting the board.

Implementation

So the M3 Specification was agreed on with old Mech (Brielle & Josh primarily) a long time ago and was used for ZP3 & ZP2 (new ZP2, yes there are multiple ZP2s). The M2 specification I’d like finalized for future hardware. If new Mech would like to make changes, now is the time.

Reason for Change

Avoiding weird screw sizes needed for our hardware. Choose something that works for EE and ME!

Priority

Medium

 

Impact of Not Responding to Change

Confusion

What Groups, People, Sub-teams Need to be Notified?

  • @Conall Kingshott

  • @Megan Spee

  • Electrical

  • Mech

  • @Michael Botros

Change Impact

Additional Parts/Resources Required and Costs

None. Saves money long term on wack screws.

Impact on deadlines

Sooner the better. Projects are ongoing.

Alternatives and Recommendations

Alternatives: Confusion.

Recommendations: Acceptance.

Comments

None.

Change Request Sign Off <System Integration>

Status

Approved by Anni and merged

Accepted / On Hold / Rejected / More info Requested

Comments

Signatures/Name