Ideas wanted for the best way to cut small rectangular holes for gauge

[Wolvenar]

I have a .75" by 2" digital voltmeter I want to put in an enclosure but not sure of the best or easiest way to cut the hole in a fairly heavy gauge powder coated enclosure without damaging the powder coat or having a crappy looking job done.
Larger holes have never been to much trouble, but the small size and tight tolerances to still look good make it tough.

Anyone have any good advice?

[Rover]

Hi Wolv,

Without knowing the actual thickness, I'd probably go with a nice fine cutting jig saw blade, after having drilled out the corners to match blade width.

If done slowly and the right blade, will make easy work of it.

You other option is to create whatever hole you want, and then pour your on bezel using epoxy.. (I've done this numerous times)


Rover

[Rover]

...You don't have to pour a bezel.. you could always just mount to plexiglass (cut out).. and then mount the plexiglass.

Nice effect is to spray paint the undersinde of the plexiglass..

Rover

[ksouers]

Mill it out if possible. Otherwise chain drill it with small holes and finish with a file. Only cut towards the powder coat with the file, never away. That's when it'll peel. It may help to cover the area with tape before drilling and filing. Mark out your hole on the tape. Remove the tape by peeling towards the hole.

Something else that may help is to score the powder coat with a razor before doing any work on it. Mark out your hole and score on the line. That should prevent any chips from extending beyond the hole.


Kevin

[rossw]

not sure of the best or easiest way to cut the hole in a fairly heavy gauge powder coated enclosure without damaging the powder coat or having a crappy looking job done.

In the past, I'd put masking tape over the surface, marked it out using fine pen, then drilled a large hole somewhere inside the lines, and used a hand-held nibbling tool. Working up the the lines you can get a nice finish and dead square corners. Finish with a flat file, Peel the masking tape off and its done.

More recently, I've been using my lathe with a VMA and a small slot-drill to get an appropriate radius corner. If set up properly, the DRO lets you work to high precision (1/1000 of an inch if you wish, easily).

Here, I'm doing 4 panels at once.


The cutout I required was smaller than yours, for the RJ45 connector. But they still turned out perfectly.

[Wolvenar]

One thought was the cover of the Xantrex charge controller, it would look rather nice in there if I could do it properly, but seems like awfully tough hardened metal.
The other possibility is in the door of the main disconnect, but that is not as easily portable and nice to work on.
Its probably better to put into the disconnect since future upgrades or charge controller failure would then remove the voltage meter.

I was just thinking I also would be ok to put it in the box with the amp meters * yeah don't think "well duh" quite yet*
There was not going to be a dedicated line into that box with both poles at the battery voltage.  But the more I think about it the more sense it makes.

This is significantly thinner metal , not hardened enough to speak of, no thick powder coat, and well, just makes sense to keep the gauges together I guess. Oh and I *can* remove that cover to work on.

[rossw]

There was not going to be a dedicated line into that box with both poles at the battery voltage.  But the more I think about it the more sense it makes.

If you were trying to minimise the potential for a short circuit, you could run just a very light gauge wire from the other battery pole and feed it through a modest resistor - 10R for example. Won't affect your voltage readings, but will prevent a nasty accident.

[Wolvenar]

It's more a matter of simplicity, neatness, and trouble running it back along a bunch of conduits and connections.
But it is the best option I guess.
But that is a great idea.

[WooferHound]

How to drill a square hole

[ghurd]

A nibbler works well, though I never used one on something powder coated.
I had a few more expensive ones that do not work as well as the $15 one from RatShak.
G-