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Cleaning the black metal casing on vintage Hi Fi

maelstrom

maelstrom

New Member
Hi All, this is my first posting and I'd just like to get advice on what to do about cleaning the black metal casing of a pioneer tuner I have just purchased. The faceplate is all good but the top wrap-around casing is patchy and shiny in areas. It seems a little mottled. It looks like someone may have rubbed away at areas with solvent that has affected its consistent matte finish.

There is grime on it too but I don't want to make it worse by using any old solvent. So any advice on cleaning materials would be much appreciated?

There could also be rust coming up underneath. Would anyone recommend a full treatment and re-paint? I wouldn't want to sand it back though as there is a kind of bumpy texture that these amp/tuner casings have that I would like to keep. Maybe there is a paint finish that mimics this? Layers of thick spray paint?

Thanks all. :banana:
 
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I use Goo-Gone to remove any nasty sticker residue or other contaminants first, and then hot soapy water (top plate off of course). This will give youi an idea of how bad it actually looks. I'm familiar with the type of finish on the Pioneer stuff, and I probably wouldn' attempt to re-create it. As long as the actual color has not been rubbed through, I think I'd recommend a matt clear finish, readily available from Krylon and others. One thin coat should restore the consistent finish for not too much effort. The closest match to the original paint would probably be Hammerite, which is a kind of mottled "hammered" finish.
 
W/o pics is tough to call...But, for big metal shrounds and such, if it's that bad...I'll typically strip it. Then, Primer, sand, primer, sand, paint, sand, paint, sand, paint, etc..etc...Clearcoat, then finish it off with good rubbing compund.
(Of course, thats a gross oversimplification of the process.)

Black is THE toughest color to match (In my opinion anyways), so if it's bad enough to warrant a repaint, I'd strip it all down, and start from the square one.

Someone makes a hammered finish in a can I just saw it last weekend, though I've never tried it, and I don't know if it's made it to NZ yet.
 
Find a cheaper microfiber cloth and wet it with a solution of 1 part Murphy's Oil Soap and 4 or 5 parts water.

It will clean up real nice and the Murphy's will leave a nice sheen.
 
Radioboy said:
W/o pics is tough to call...But, for big metal shrounds and such, if it's that bad...I'll typically strip it. Then, Primer, sand, primer, sand, paint, sand, paint, sand, paint, etc..etc...Clearcoat, then finish it off with good rubbing compund.
(Of course, thats a gross oversimplification of the process.)

Black is THE toughest color to match (In my opinion anyways), so if it's bad enough to warrant a repaint, I'd strip it all down, and start from the square one.

Someone makes a hammered finish in a can I just saw it last weekend, though I've never tried it, and I don't know if it's made it to NZ yet.
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Radioboy has it down; the process and the color matching. Black (or white, especially glossy) surfaces will show every defect possible in the finished product. That being said, I recently used the Rust-oleum Hammered spray paint on a project. It can safely be sprayed over rusty surfaces and has a textured "hammered" finish. I don't know exactly what the black paint looks like that Pioneer used to use, so go down to your local hardware store and see if you can find a suitable match.
 
specialidiot said:
Find a cheaper microfiber cloth and wet it with a solution of 1 part Murphy's Oil Soap and 4 or 5 parts water.

It will clean up real nice and the Murphy's will leave a nice sheen.
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+1

I sure can appreciate re-finishing pieces, but really, this what I would do.
 
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Beadblast the entire case.Remove all the paint and rust.Have a local powdercoater coat it with gloss black. You'll thank me..:thmbsp: Way more durable than rattle-can paint.Will look like a brand spank'n new case.
Might set you back maybe $5-10. I had 9 pieces done and the coating charge was $20.I did all the beadblasting.It may cost a little more if they have to do the prep work.
 
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If you have to refinish this is what I like to do. Go to your local Harley Davidson Dealer,, yep that’s right. Go to the parts counter and purchase a can of HD black wrinkle paint. HD has made for them the best I have ever found. Clean and prep the surface and paint per instructions on the can. You will end up with a semi gloss black wrinkle coat that will rival any factory job you have ever seen and it will not show hand prints.
 
avionic said:
Beadblast the entire case.Remove all the paint and rust.Have a local powdercoater coat it with gloss black. You'll thank me..:thmbsp: Way more durable than rattle-can paint.Will look like a brand spank'n new case.
Might set you back maybe $5-10. I had 9 pieces done and the coating charge was $20.I did all the beadblasting.It may cost a little more if they have to do the prep work.
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I'm a fan of PC'ing too, on certian applications...And again, I'm not familiar with the casing/shroud in question...

But, the only reason I didn't initially suggest it, is because (I'm no expert, so correct me if I'm wrong) the "coat" is typically thicker than paint, and that leads me to 2 issues:

1) Thermal Radiation might be affected. IE, the dissipation through the metal might slow, and a thicker coat might affect the openings of small louvered/grated cases. Normally not a big deal, but with precision electronics, it might cause overheating.

2) You may have to mask/block off the screw holes. Most chassis use machine threads, so you might chew up the PC material after it's been applied. Unless the chassis uses high-pitch threads.

I'm opining out loud here...so if these issues are neglible, powedercoating might be a great method to use!
 
Most outer cases just have holes for fasteners to go through.At least on Yamaha cases .I have had to run a tap through threaded areas on various other pieces. Black coating will radiate heat the best.But most covers have louvred slits and holes for ventalation. After rereading the OP's post.You'll have to check with your powdercoater about a textured finish.
We contract a PC firm quite a bit where I work for refinishing laboratory cabinet doors and drawers.
 
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Short of repainting, try Meguire's Paint Cleaner and Restorer. Clean any heavy dirt off first, before using the product. Apply with cotton cloth, and if the surface is relatively smooth, wipe off with soft paper (without creases; sharp paper edges of folds can leave marks in paint), then buff with cotton cloth again. You may need to repeat the process. There is a bit of an art to knowing when to do which step (when cotton? when paper? How much?), but with a little experience and practice you'll get a feel for how this stuff works. Used correctly, it works GREAT! I've had some dull, oxidized paint finishes come back to looking like NEW again, after using this stuff.

Of course, it cannot restore scratches or gouges through the paint, chips, etc... If there are issues like those, then a strip-and-repaint is in order, as others have been describing.
 
J B S said:
If you have to refinish this is what I like to do. Go to your local Harley Davidson Dealer,, yep that’s right. Go to the parts counter and purchase a can of HD black wrinkle paint. HD has made for them the best I have ever found. Clean and prep the surface and paint per instructions on the can. You will end up with a semi gloss black wrinkle coat that will rival any factory job you have ever seen and it will not show hand prints.
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y'know, that is a great idea.

The paint you're describing is just about perfect-- and very heat tolerant. I hope I remember this next time I'm painting an amp chassis or transformers.
 
avionic said:
Beadblast the entire case.Remove all the paint and rust.Have a local powdercoater coat it with gloss black. You'll thank me..:thmbsp: Way more durable than rattle-can paint.Will look like a brand spank'n new case.
Might set you back maybe $5-10. I had 9 pieces done and the coating charge was $20.I did all the beadblasting.It may cost a little more if they have to do the prep work.
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Did you do the beadblasting at home?
(if there is a way to DIY it I would love to learn how. I haven't had done it since I worked at a snowmobile shop)
 
oneinchside said:
Did you do the beadblasting at home?
(if there is a way to DIY it I would love to learn how. I haven't had done it since I worked at a snowmobile shop)
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Not yet but I'm working on it.I use the beadblasting cabinet at my daytime job..Been looking at various cabinets.I want to be able to recover/reuse blasting media and filter out debris.Like the one I use at work.
 
avionic said:
Not yet but I'm working on it.I use the beadblasting cabinet at my daytime job..Been looking at various cabinets.I want to be able to recover/reuse blasting media and filter out debris.Like the one I use at work.
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Now that I think about it, it'd just be a good excuse to go back and hang with some of the guys I used to work with, which is really enough to make me want to redo an amp all on its own. :thmbsp:

But I hear you about recovering the the media, that stuff gets expensive.

I'd really like to blast wood as well, but I think Scott'd kill me if I left wood dust in his cabinet-- but I'd love to have a couple of blasted guitar necks, hard wood knobs, (cedar, maple, mesquite...) makes for a great finish.
 
Ah, you guys are awesome! Will see what options I have in New Zealand (re: cleaning products) and we do have a Harley shop and powdercoater places, of course, so I will look into these options. I'll try cleaning first but there are some chips so a full makeover may be in order. Thanks to everyone. Will use images for future questions as I agree they help. Cheers.
 
No need to start a new thread.

I have Kenwood KA-5700. I want to powder coat the black casing. I have access to a sandblasting booth at work, with the same garnet sand used in our waterjet machine. I figured it would be a pretty easy job to remove the coating, but I was very wrong.

The thin paint on the backside came off with ease, but the top is very difficult. I was able to crack through on one of the corners, from there I could sort of angle-in under it, but the picture below represents the progress of about 15 minutes. At that rate, it would be many many hours and I don't know how designed that booth, but it is NOT ergonomic.

Anyone have experience with this type of coating? Is there a chemical treatment I can use instead of, or before the blasting?

blasted.jpg
 
avionic said:
Beadblast the entire case.Remove all the paint and rust.Have a local powdercoater coat it with gloss black. You'll thank me..:thmbsp: Way more durable than rattle-can paint.Will look like a brand spank'n new case.
Might set you back maybe $5-10. I had 9 pieces done and the coating charge was $20.I did all the beadblasting.It may cost a little more if they have to do the prep work.
Click to expand...

You are getting a GREAT deal from your powder coater, Avionic. I own a coating shop and the goin' rate in the DFW area would be around $10-15 for a top cover off your average size amp.

To the OP....if you have a powder coater in your area I'd certainly second Avionic's suggestion to look into that if you want better than just a cleaned up original finish. If you can find a shop that will do it for less than $30 you'd get a scratch and chip resistant finish that will last as long as the unit. It's simply the best coating technology available for the money.
 
I agree, something that has been powder coated is VERY durable and resists all kinds of chips, stains, etc. in the future. If you go this way, the top will look brand new for many years to come.
 
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