[sdiy] Eurorack panels DIY

[David G Dixon]

> > I didn't see any responses for suggestions for the hole punch and 
> > whether or not the Harbor-Freight shear is sufficient for our 
> > purposes.
> 
> Shear area in mm² multiplied by shear strength in MPa gets 
> you a force in N. For example, for a 10 mm round hole in 3 mm 
> thick 2017A aluminium in T42 state,
> 
>   10 * 3.14 * 3 * 390 = 36_738
> 
> I.e. you would need a 3.7-ton punch.
> 
> 390 MPa is towards the high end for aluminium alloys. Some 
> alloys/states are less than half of that.

First, production eurorack panels are typically 2 mm thick.

Second, shear strength for Al is way less than 390 MPa.  5052 is about 130
MPa, and 6061 is about 210 MPa.

Third, you will almost never be punching a 10-mm hole in a eurorack panel.

Conclusion: you shouldn't have any problem punching Al eurorack panels with
a benchtop 3-ton press (like the Baileigh BP-3).

The only drawback: the press will set you back about $700, so you'd better
want to be punching a whole hell of a lot of panels.