Project Enclosures

[Bottesford]

I'm new here and was wondering if I could get a few ideas/tips on enclosing an electronics project.
I'm building a DMX controlled power supply for disco lighting which will require a number of inputs & outputs (mains in, 8 x mains out, DMX in & out, etc).
The problem is, although I'm confident with the electronics side, my DIY skills are less groomed (an understatement!)
I need an enclosure to put the project into and a way of mounting sockets within it. How do others go about this? What sort of enclosures do you use? How do you go about making well formed holes to put sockets into?
Any other tips?

Thanks for any help!

 

[poopeater]

I'm no expert, but I've had good luck making holes and enclosures using rudimentary tools.

1. Hacksaw
2. Jigsaw
3. Drill
4. Clamps of various kinds (c clamps and spring clamps)
5. Dremel tool (this one is most important)
6. Assorted files (the dremel can potentially replace the need for these though)

 

[hjames]

I'd be kinda wary of trying to get that many holes to line up in any well-behaved manner by hand.

Quick questions: Whats the budget (i.e. 0?) and how pretty does this need to look?

My first reaction would be to veer towards mangling some pre-existing cases. You can buy rack-mount AC outlets, or some metal-cased power strips modify them appropriately.

James

 

[dknguyen]

Get a drill press rather than a hand drill. I got a little one for $40...kind of wish I had spent twice as much to get the kind where the bench is raised and lowerd by a crank rather than a vice grip...then again, I was pretty harsh with it and the bearings are making noises now so maybe it's all for the best.

 

[poopeater]

Get a drill press rather than a hand drill. I got a little one for $40...kind of wish I had spent twice as much to get the kind where the bench is raised and lowerd by a crank rather than a vice grip...then again, I was pretty harsh with it and the bearings are making noises now so maybe it's all for the best.

I always end up regretting going cheap when I get tools. It's worth it to spend a little extra to get what you really want. I can't even begin to count how many cheap tools I've broken just to have to go back to the store and get another.

 

[eblc1388]

While we are on boxes openings, how do everyone cut holes for component like fuse holder or switches that has a "D" shape shaft(some portion cut away) to stop it from rotating in the mounting hole?

I drilled a smaller hole, file away and trial many times and it usually takes a very long time until the part fits. Hate them.

 

[hjames]

While we are on boxes openings, how do everyone cut holes for component like fuse holder or switches that has a "D" shape shaft(some portion cut away) to stop it from rotating in the mounting hole?

I drilled a smaller hole, file away and trial many times and it usually takes a very long time until the part fits. Hate them.

You're supposed to buy some horribly expensive punches: https://www.mygreenlee.com/products/Holemaking.PDFs
see page 34, Newark has the .5" one for ~$200.

 

[dknguyen]

While we are on boxes openings, how do everyone cut holes for component like fuse holder or switches that has a "D" shape shaft(some portion cut away) to stop it from rotating in the mounting hole?

I drilled a smaller hole, file away and trial many times and it usually takes a very long time until the part fits. Hate them.

I've been trying to think of a solution to that myself...a dremel cutter and mill-bit with steady hand seem like the best thing right now? The only other things I can think of are massive punches or a mill which are totally excessive. Any better ideas? I guess you could always just drill the hole then weld/braze/CA a piece of material across the hole to make the flat side.

I always end up regretting going cheap when I get tools. It's worth it to spend a little extra to get what you really want. I can't even begin to count how many cheap tools I've broken just to have to go back to the store and get another.

Yeah, but I kind of treated this drill press like a milling machine by drilling out some screws that were very out of reach. Lots of flexing going on so it damaged the bearings- but it was cheap! I should have just used a Dremel but I don't own one.

 

[HiTech]

Greenlee chassis punches are expensive but worth it when saving time and excellent finished results. Otherwise it's drill a hole and file manually. Dremel type tools work well in soft materials but for steel chassis, they are noisy as hell and take a long time, often destroying bits in the process.
It's saddening when I see a talented electronic builder ruin a project because he doesn't take the effort for good physical and aesthetic construction of his project. I see that often. About the only way one can get by using a hand drill for holes is to use a center punch to initially lay out the holes in good alignment. Even then hand drills can walk across a panel ruining it. Use brad-point drill bits to reduce that from happening. A small drill press and a drill press vise with jaw protectors goes a long way to professional results and holes get drilled cleanly. Labeling is another area that should be as professional as possible... not resorting to using those stoooopid looking DYMO label makers! Often I'll use dry transfers on panels then apply 2-3 coats of clear laquer atop that.

I have a fully equipped larger workshop that has full-sized powertools and air tools for cutting, but in my smaller electronic shop, I use the $40 drill press shown below, mounted atop a mobile tool chest and employs a chuck that will tightly grip a tiny wire drill bit and has selectable speeds. With a 20% off coupon it cost me a mere $32 for accurate drilling/milling:

**broken link removed**

 

[stevez]

The hole problem is quite the challenge and I can't add much to that. For the enclosure or chassis I use aluminum sheet that I cut to size on a table saw. Getting a straight cut is a challenge but it can be done with home-made tools. Rather than try to bend the stuff - I use machine screws and solid bars of 1/4 inch square aluminum - tapped with 6-32 or 4-40 threads. I keep hole centers at uniform intervals. What you end up with is something where you can remove any side for access - handy when you are working your way thru a project.

For some things I'll actually use wood - with front and back panels of aluminum sheet.

Laser or plasma cutting from CAD files is so common now. I do not know if they cut other materials besides steel with it. If faced with the problem you describe I would construct my chassis in whole or part from flat panels. Then I would:

1. Make a CAD drawing of the panels with holes - drawn exactly as your want them. Describe the material to be provided - most likely some thin sheetmetal.

2. Give the drawing to my brother. On his next order to his steel supplier he would include the drawing and description.

3. The supplier would laser or plasma cut the dimensions including holes. My brother tells me that the finish and precision of this process is excellent. Cost is very modest.

4. Clean and paint.

With the above laser/plasma process in mind - you might make up a bunch of square or rectangular plates - with single holes in them of the desired shape. You might then fix these over larger holes with neatly drilled screws. You might even make up plates with multiple holes in.

 

[HiTech]

Holy $hit.... laser and plasma cutters, CAD drawings, CNC machine shop? Are you crafting PC tower cabinetry? LOL There's a nice netal shop at my work place and sometimes I will use the cutters / benders there but on rare occasions. Otherwise I scavenge cases from discarded equipment and adapt the board and controls to fit. Repaint and label accordingly... done!

 

[stevez]

Access to some of these processes is easier than you might think, in some cases. Some small shops, with this equipment, will do cash orders for people like us - as fill in work. 5 yrs ago or more I was amazed when my brother told me how he orders sheetmetal or boiler plate that he previously drilled, cut out or otherwise machined. He said that he does a quick AutoCAD sketch (he's a machinist not a CAD operator) or passes on the customers CAD files - and for the price of the material they do the holes, cutouts, etc. The material is on the table to be cutoff - so to attract customers the supplier offers the extra service.

Bottesford's needs may be minimal but he might know someone with access to this kind of thing - which is why I mention it. The thought got me to thinking that I might make sketches of some things like that to get done with the next order.

 

[Bottesford]

Thanks for the ideas everyone. Can't say I know anyone who could do CAD based cut outs but will look round for somewhere like that.
Last time I made a project I used plastic enclosures from Maplins (not sure what the US version of Maplins is!), made some holes with a drill then attempted to use a hack saw blade to form a square cut out. Obviously it looked pretty shabby but did the job. This time I want to get it looking good. What material would you use for something 200mm x200mm x100mm (8'x8'x4')- plastic or metal? I'd tend to favour plastic as its easier to work with but doesn't look as nice.

 

[philba]

to get back to the original question. I design my PCBs with a specific case in mind. You can buy cases with removable panels, sometimes plastic, which makes it a lot easier to cut/drill. Pactec and serpac have lots of boxes and have detailed draws for your planning purposes. Many of them have PCB outlines with mouting holes.

as to holes and such. I try to select components that are forgiving. snap-in switches that have a collar that hides the hole are good examples. potentiometers - use a nut/washer that hides the hole. or a big knob. do a carefull layout of your drill plan. make a test run on similar material. have an extra panel for screwups.

 

[HiTech]

Hey philba, so what you are saying is that you'll never get a job working for NASA or Intel and that you drill ellipticle holes and hide them with panel componets that have a square bezel?

 

[philba]

addendum. square holes are tricky. drill the corners and then the middle with a larger bit. then use a nibbler to clean up the edges. they are pretty cheap and require a bit of experience to control them you can do a pretty respectable hole with them. Usually, I'm making them for a device thathas a collar so it doesn't have to be perfect.

the trickiest are the db9 holes. I've never been able to make them look good. I'm keeping my eyes open for a used punch for that.

 

[philba]

Hey philba, so what you are saying is that you'll never get a job working for NASA or Intel and that you drill ellipticle holes and hide them with panel componets that have a square bezel?

funny, I worked at intel for 8 years. maybe you should read my second post.