Useful cheap small tester...

[AlanBeckett]

The most difficult part was cutting the rectangular holes for the display & socket

I'm glad I'm not alone

Alan

[Old Sparky]

I cut the holes by first drilling around marked lines, than filing them out to get the openings as rectangular as possible.  There must be an easier/quicker way, surely!  Anyhow the photos below will give an impression of what is still a 'work in progress', as I want to fit clear perspex 'lens' over the display, maybe add individual 4mm sockets in parallel with the ZIF one, fit a bracket to hold a PP3 battery (at the moment I'm using a PP6 I happened to have handy), and maybe an on/off switch to prevent the meter turning itself on whilst being carried.   Incidentally, the tester I bought has the larger display PCB, and I don't see how it is posible to fit a mounting screw in the top LH corner (as viewed from the front), hence only 3 screws securing the display to the case!

           

[AlanBeckett]

OS,

I gave some consideration to clamping it down to the Milling Machine and running round with a 1/8" Slot Drill but it seemed a bit OTT, so I made a muck of it like you

Alan

[Old Sparky]

It actually looks better in reality, than in those photos, Alan. For a start the plastic box is Black, not that bluish colour, and there's only one mark long the LH side, which was one of the guides line for the Display aperture. That having been said, with more suitable tools, it would have looked neater.

[AlanBeckett]

Yes, I actually think mine looks better in real life than on the Pictures.

Alan

[Yorkie]

If I cut apertures in plastic cases I drill holes almost up to the line at slow speed in a pillar drill with the plastic supported underneath on a block of wood and held down firmly so that it doesn't 'ride up' the drill bit, then I use a sharp woodworking chisel and craft knife to pare away the waste up to the line.  (Plastic doesn't respond well to files). You need to pare away thin slivers of plastic at a time and keep good control of the tool. You can always take a bit more off, but you can't put it back on!

When I scribe lines I do it from both ends to meet in the middle and have the rule so that the line is on the waste side. That way, you don't get lines where you don't want them.

It's amazing how discerning the eye can be at detecting small defects, as we known only too well!

I'm one of those insufferable pedants who - when visiting other people's houses - feel an irresistible urge to straighten wonky pictures and mirrors. Probably borderline OCD, if not full blown.

As quality controller of my own work, I often reject it as sub-standard at the first attempt, then do it again, and hopefully get it right.  

[Old Sparky]

I didn't think of using a Craft Knife, David, and I don't possess a Pillar Drill, so I drilled the holes, using a Hand drill and with the box clamped in a small bench vice. Not, perhaps, the easiest way to do it, but the only option open to me. I've often cut & drilled metal boxes & chassis that way, but seldom, if ever, plastic ones. At one time it was possible to buy 'Q' Max rectangular Cutters for metal, but not sure if they're still even made. As for scoring lines, it was just easier to do this on the outside of the box, rather than the inside, but why I ran that line all the way up the LH side I know not!

[Nick]

Nibblers are quite good for this...

[Yorkie]

 At one time it was possible to buy 'Q' Max rectangular Cutters for metal, but not sure if they're still even made.

Yes, you can still buy them (if you have a deep pocket!):

https://www.google.co.uk/search?q=square+q+max+cutters&sourceid=ie7&rls=com.microsoft:en-GB:IE-Address&ie=&oe=&rlz=1I7ADRA_enGB420&gfe_rd=cr&ei=635CVd7-HcLCaPTugMAJ&gws_rd=ssl#q=square+q+max+cutters&rls=com.microsoft:en-GB:IE-Address&tbm=shop

Yikes!!!