Enclosure Questions

[tehfunk]

I have been reading around all sorts of articles about prepping an enclosure and getting everything put inside, and the painting process and all. I was wondering that if I don't want to do any painting is there anything that the box requires besides drilling the holes for the components? I ask this because the enclosures you receive seem quite dirty at first and I couldn't imagine that you would want to just drill them and put everything in, is their a good cleaning process? Also, (this is going to vary with people's opinions) what do you think are the best things to do to an enclosure that doesn't mean changing it from it's metallic state, meaning no etching, painting, or artistic processes. I mean like sanding. Thanks!

[darron]

dirty? do you mean the insides or outsides? it all really depends on what you want to do with them. from the factory, they do come pretty crude and rough. you'll either be able to see deep ouges on the sides where they sanded it or you will see the remains of aluminium on the lip from where it was die-casted. for the insides you don't need to do anything and anything that touches the enclosure that you want to, like the jacks, should have good continuity as it.

if you want to paint it or whatever, then yeah, you'll need to do lots of sanding and cleaning. i don't mind the flakey look of the raw aluminium for a DIY pedal, it shows how obvious it is that you made it yourself.

as far as raw metal finishes go, you can sand it back gradually from about 100grit to 800 and it makes a nice finish (just ignore the etching):






or you could sand it with an orbital sander, which leaves a non-directional sanded pattern. no pic. i don't think it looks as nice, but a valid option.




or you could buff it even further to a mirror to look like chrome sorta:


you'll need a buffing wheel and compound for that one.





or you could put a wire brush in your drill and get effects like this:






then you have to decide if you want to clear coat it to protect it from corrosion from the acids on your hands etc. i like it raw, even if it discolours here and there.

hope that helps.





edit: i don't bother doing anything to the bottom plate. it shows what it was originally like raw, and the work i put in.

[tehfunk]

Thanks for all the info and options that's exactly the kind of answer I was looking for, but when I say dirty I mean it feels like there's, I don't know, dust on it? It might be like left over metal from their process. But yeah if the inside is dirty like that, should I clean it like will it affect the functioning by maybe dirtying the components?

So yeah, I like the idea of just a raw metal finish, so what should I do besides sanding it back gradually from about 100 grit to 800? I'm sure I'd have to clean it off with something after the sanding process and probably before, what should I use? And, if I just do the sanding will the metal still corrode from acids on my hands if I don't put a clear coat on it? What should I use for the clear coat if I need to use it? Thanks!

[earthtonesaudio]

If you're using aluminum enclosures, they won't really corrode, but they will get fingerprints, discolorations and tarnished-looking spots from skin oils.  Steel, on the other hand, will rust very soon if it's a humid environment.

As far as the inside of the pedal goes, if it really bugs you you could take a Scotch Brite pad and maybe some soap and water and give it a quick scrub.  If you want to go further you could use vinegar and baking soda to put a little polish on it.  Otherwise, I doubt you have anything to worry about with components getting dirty.


...Unless, however you are using NOS super early-model transistors.  Some weren't made that well, and the leads will just rot right off them.

[tehfunk]

Thanks, yeah I guess I'll clean it out a little with some and water. But, I still want to know what else do I have to do once I have sanded the box down, like what do I clean it with? Also, what is acetone used for? Thanks.

[darron]

clean it so there's no crap to fall on your board, but it wouldn't matter. maybe just hit it with some steel wool once its drilled in the areas where the jacks go so that they make a good connection to the case. this will be used for proper shielding after all.

as far as sanding goes, hit it with wet and dry and a block. if you are doing just the one, then you can do it by hand and it will be quicker than a block, but doing more will give you blisters. start to get all of the deep gouges etc. out with something really thick. make sure that you are happy that you can do no more before you progress to finer sand papers, since if you progress to something finer then you probably won't be able to.


acetone is something that you can use to properly clean the box before painting. when you paint to something, the surface quaility is crucial for a good and strong finish. if there's a microscopic film of oil on the box then the paint won't stick there properly. after you acetone it (or use metho, ethanol (pure alcohol), lighter fluid, etc.) then don't touch it with your hands. prop it up on something and give it maybe 3-4 coats of clear. wait about 15 minutes before spraying each coat, and no more than an hour between each coat. spay every coat as thick as you can without having any runs for a smooth glossy finish. remember that you can spray the flat surface much more than the sides which could drip very easilly. for the clear, you can use an enamel, or an acyrlic, or my favourite; a polyurethan designed for spraying aluminium car wheels! that's the strongest stuff you can get for the job. the other paints aren't really designed to stick to metal without spraying a primer first.

give it weeks before it cures fully. i generally don't have good luck baking clear coats because they discolour to a yellow-ish colour, even at lower temps.



why not just sand it back and try leaving it as it is for a while? if you don't like it then you can always sand it a bit further in the future and clear-coat it then. paints can always chip/scratch. especially if they were not professionally done.