Sanding surface of powdercoated enclosure

[.Mike]

Over in the pictures topic, HOTTUBES posted an pedal where he painted the enclosure, and then used a razor to scrape the paint off the top. That inspired me to try something.

I've got a ton of blemished powdercoated enclosures that I bought from someone here. Unfortunately, most of them are dark green, so I have been looking for a way to lighten up the top, or even etch them. I ended up taking a random orbital sander to one of them today. The results are pretty good.

The base enclosure had bubbling and pitting on the top (and the sides, but I don't care about that). After about 30 seconds with 80 grit, I was left with a pretty cool looking lightened and swirled effect. I think it looks cool enough to be usable, and I bet using a higher grit sandpaper would yield even cooler results:



There were no interesting results between there and when the whole top was sanded. I used 80 grit until the powdercoating was gone. There was no melting, and surprisingly little dust. I continued until the pitting was gone. This took about 10 minutes. I rotated the enclosure ever thirty seconds or so. From there, I went up to 100 grit for about 2 minutes, and then up to 220 grit for about 5 minutes. After a while of using the 220 grit, I could feel and hear the paper making better contact with the aluminum, so that is when I knew to stop. I want to go up to a higher grit, but I can't seem to find my sanding disks.

Here is the final result:



It ended up with a nice, crisp line where the bare aluminum meets the powdercoat.

If you decide to try this, I recommend putting about 8-10 layers of tape around the bottom edges of the box. I placed mine on a piece of wood to sand. Sand and paint dust came off the enclosure and onto the piece of wood, and the vibration of the sander caused it to scuff the powdercoating on the edge. Tape fixed it.

Now I am going to try to etch something onto this. I'll make sure I tape where the aluminum meets the powdercoat so I don't have to risk damaging the powdercoat with nail polish remover. I'm not sure if the heat from the iron will damage the powdercoat, but I am thinking it will hold up to the heat. If it doesn't hold up, you can always use nail polish and free-hand a design onto the top.

All in all, I am happy with how it turned out-- especially considering I have 7 more of these same green enclosures.

Just thought I'd share.

Mike

[Earthscum]

Those look pretty nice!

One thing you may try is putting tape around the top, maybe 2 layers tightly wrapped, and then sand the top down. I think it will help eliminate chipping around the edges. Just sand the tape (edges) down like it isn't there, and peel the rest off when you're done.

[.Mike]

So the powdercoat was able to handle the heat of ironing on a transfer for etching without any problems. I ironed for almost 10 minutes for the transfer. The powdercoat did seem to get a bit sticky, but it hardened right back up.

The etch went really well. I taped it all off, and painted the seams with nail polish. I applied the etchant with a q-tip for better control.

If you etch one of these, make sure you are careful when removing the toner. Acetone will eat powder coat, although very slowly and only with a lot of pressure.

Here's the final result-- a Rebote:



There are a few flaws, but it is much better than my last etches. I had already drilled my enclosure, so I was unable to line up the lines that connect the LED to the switch. I etched the top lines by the knobs too deep. And, I etched the labels too deep, causing the little nub in the A to get eaten away, and some of the letters to run together. I'm getting better at etching, though!

Those look pretty nice!

One thing you may try is putting tape around the top, maybe 2 layers tightly wrapped, and then sand the top down. I think it will help eliminate chipping around the edges. Just sand the tape (edges) down like it isn't there, and peel the rest off when you're done.

I really didn't run into a problem with the edges. The one image I posted looks like it chipped away the powder coat, but I think that was glare or something-- the edge is crisp and smooth.



Mike

[Kearns892]

Wow, that is a great looking etch. I love the cleanness/ simplicity. Thanks for sharing your methods.