plastic enclosure

Nick · Guest

I have found many plastic enclosures on mouser.com. I want to use one of those enclosers and modify it so I can use two dials, DB9 port, and lcd screen. I dont know where to start. I believe that using a drimel with drill press would give me some very nasty results. I'm open to any ideas.

Nick

John Morley · Joined: 09 Aug 2004 Posts: 97

Nick,

Well, you're basically on the right track. You could take the enclosure to a machine shop and they could do it with a CNC milling machine, but you'd need to do a lot to justify the price. For small quantities and prototypes I mark the outline on the plastic (old PC angle brackets are great for D-cutouts) and use a small drill bit (about 1/8") to go all around the marked line just inside the line. Finish out to the line with a file to make a (mostly) clean and neat opening! Not too fun, but it does work!
_________________
John Morley

kender · Joined: 09 Aug 2004 Posts: 768 Location: Silicon Valley

Your life will be a lot easier if you choose the enclosure with separet front and/or back plates. That way you will not have to set the whole enclosure in the vice. Also, if you screw up a plate you will not screw up the rest of the enclosure.

Nick

kender · Joined: 09 Aug 2004 Posts: 768 Location: Silicon Valley

By the way, if you're local to the SF Bay Area, I might be able to help you out - I have a manual mill and a drill press.

nick@ismtech.com

Sincerely,
Nick

newguy · Joined: 24 Jun 2004 Posts: 1903

Nick,

Take it from one who knows - if you use a dremel, don't try to work all the way to the edge of the cutout. Get close, but not too close. One slip, and the enclosure is hooped. Finish up with a file, and the results are actually quite good.

There are some other tricks - like trying to avoid rectangular cutouts whenever possible. It's easier to drill a clean hole that to file a rectangular one.

Use a good graphics package (I use CorelDraw, but any package would work) to lay out the front panel/connectors/whatever. Print it out, place the paper over the enclosure, and carefully cut around the intended holes with a really sharp x-acto knife. Mark the center of circular holes with a +. Once that's done, have at with the drill, dremel, and the files.

For placing text on the enclosure, go get some avery self-adhesive labels from any office supply store. The white ones look good on a black enclosure, but the clear ones look awesome on a grey enclosure. Print out your front panel on one of these sheets, then stick it on. If you let the label dry for an hour and use the sheet's backing to rub it on, you won't get any smudging of the letters. Then cover this with a clear laminating sheet (again, from an office supply store). Use an x-acto to carefully cut out around your openings for the lcd, buttons, whatever, and you're done. You'd be surprised how professional it looks when you're done.

Nick · Guest

Thanks for the great tips!

Nick

bdring · Guest

I have used hand punches from Greenlee www.greenlee.com

Look under holemaking products. They have all the d-sub connector sizes. Some plastics may crack, but it has always worked for me

rnielsen · Joined: 23 Sep 2003 Posts: 852 Location: Utah

One way to get a nice straight cut, for a display, is to take some sort of straight edge, like a metal ruler, and use the back side of an exacto knive to 'scrape' the plastic away, layer by layer. I've done this many times and it makes the edge look nice. It takes a little bit of time but it is easier than trying to cut through the entire thing with the sharp side. Otherwise, about the only thing you can do is drill holes around the edge of the cut-out and then clean it up with a file.