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Drilling enclosures

Today I was on holiday from work, but I'd also done some thing to my back that meant once I sat down, I was in danger of not being able to stand up again, and my intentions to go out on my bike and put some miles in were well and truly scuppered.

So to keep myself active, and in a standing position, I decided to prepare a couple of boxes in advance. These were 1590A size boxes and I was preparing them for some effect that will have a single control.

First I printed out templates which I downloaded from madbeanpedals.com and taped these to the boxes. Then I used a centre-punch to mark the location of each hole I wanted to drill in order to guide the drill.

enclosures with drill templates and tools
In the picture above, you can see the two enclosures with drilling templates attached, together with a centre-punch, a couple of step drill-bits and a 3mm drill-bit for the LED.

And here is what a box looks like once it's been centre-punched.

enclosure with centre-punch indents marked
Then it's just a case of some careful drilling, preferably with a drill press. I first drill pilot holes with a  small drill bit, then use one of my selection of step-bit's to make the hole size I need.

For reference, the drill sizes I use are:-

3PDT footswitch:12mm
3mm LED:3mm (no sh*t!)
input/output jack sockets (for 1/4" or 6.35mm jacks):9mm
potentiometer (for 6mm shaft):7mm
DC jack (for 2.1mm plug):15/32" **
Other useful drill sizes not used in this project
Plastic 1.4 jack sockets: 11mm
Plastic surround for 5mm LED:1/4"
Unswitched DC jack w/internal threads:8mm (see 14-dec-17 update)
Switched DC jack w/internal threads:12mm (see 17-dec-17 update)

** [update 31-mar-15]
This was for a DC jack with external threads (i.e. threaded from outside of box). The DC jacks I had which were threaded from the inside needed a slightly larger hole (1/2"). My conclusion is that there are no standard sizes for these.

** [update 16-apr-15]
I drilled DC jack another at 15/32" and tried the inside-threaded jack and it fitted, so 15/32" does seem to be correct after all.

** [update 14-dec-17]
For 1590a builds I now tend to use the small non-switched DC jacks like the one below, and for these I use an 8mm drill-bit.

** [update 17-dec-17]
Instead of 15/32", 12mm works well (couldn't find a 15/32" drill)

I'm still not 100% happy with the template, because for the box-style jacks I'm using, the centres are not quite far enough apart, and I'm doing a bit of guess work. Also, I seem to struggle getting the DC jack centred for some reason, and the hole size is not quite right. I was using 1/2" but that was just a bit too big. 15/32" is better, but still not quite right.

Not bad though, here are the results.


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