Making rectangular holes in Hammond boxes

[mat]

Hi,

Easy and quick and cheap:

1. Draw the hole
2. Drill small holes on corners
3. Saw with fret-saw and use blade for metal working
4. Finish with decent size files

cheers,
mat

Anyone have any tips for making rectangular holes in hammond boxes for things like slide or lever switches?  Is there a good dremel bit that I should look for?

[bioroids]

I don't like PCB mount power jacks, because people have a bad habit of forcing wrong plugs in & breaking the jacks off the board (sounds impossible, until you have seen it happen a few times!). So I prefer chassis mount.

Yeas, I suppose it's safer to design for worst case, rather than assuming people will be nice with the pedal! Hopefully they don't hook it to 220v with an AC power prong :lol:

Miguel

[Paul Perry (Frostwave)]

Yeas, I suppose it's safer to design for worst case, rather than assuming people will be nice with the pedal! Hopefully they don't hook it to 220v with an AC power prong :lol: Miguel

It's suprising how 'worst' the 'worst case' can be. One of my rack mount quad midi-cv converters came back under warranty.. opend it up & some PCB track was blackened & lifted off the PCB & coiled like a watchspring. Turned out, someone thought the gate voltage (0 to 10V dc, as the note goes on & off) would do somethng useful if it was plugged into an organ(!) where someone else must have  thought a mains outlet 230v AC (on a 1/4 jack!!) would be useful.

Strangely, nobody was killed, and a 50c  op amp acted as a fuse so replacing the IC & running a wire where the trace had been had the unit going perfectly again.

There is a moral to the story, though. I SHOULD have had a 1K resistor in series with teh gate & the outside world. There are no legitimate circumstances where that would compromise operation, and it would mean you could plug it into anything you wanted. Sometimes when you look at gear & think "that resistor isn't doing anything", well sometimes "they also serve, who only wait".

[Ethan]

Draw an outline and follow the line slowly with the dremel  cutoff disk.
-ethan

[C Bradley]

Draw an outline and follow the line slowly with the dremel  cutoff disk.
-ethan

The only problem with this idea is that when the disc breaks through the bottom of the box, it tends to dig in on one side and jump out on the other. I've never been able to successfully control a dremel while doing that. The series of holes is more precise, although it takes longer. But like I said, I've got a milling machine so I just use an end-mill.