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Old 10th August 2006, 06:00 PM   #11
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Quote:
Powder Coating is good... don't expect mirrors though.
I wasn't thinking to do a mirror-finish outside, but maybe high-gloss, which I already saw on some powder-coated things. Black nickel... could be interesting if it looks like black paint.


I wonder if I should ask for both buffing and plating, considering that the equipment to do this isn't always cheap. (Well, I have a grinder and drill, but I found some aluminium polishing guides and they seem to tell that they used $40 wheels on their grinders)

EDIT:
Quote:
Yes, eventually. Start at 300 and work up.
Great!

I wondered since the Nevr-Dull wool and 1000 grit left some scratches. (Well, you see that the light reflections aren't always the same with Nevr-Dull depending on the direction I used it)
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Old 10th August 2006, 06:25 PM   #12
amt is offline amt  United States
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Depending on how deep the scratches are, #2000 will work. Start with #1000 and if that isnt taking them out, go down to #600, then #400...You dont want to put more scratches in by using too course a paper initially.

Once the major scratches are removed, I use #1000, then #2000 and buff with 3M #05973 rubbing compound. Then polish with Mothers Billet Metal Polish or similar. Other brands are fine, but Mothers is available everywhere. If you are doing small pieces, polishing by hand is quite easy but takes more time. I find that on small pieces, I get a more uniform finish than with my big buffing wheels. The piece gets hotter than hell and if it catches the wheel, it gets launched and destroyed. The photo is of a current project using copper plate. This was all done by hand.

For the black panels, just use Krylon. Semi flat black is a nice finish. Its non-reflective enough to look flat but low porosity so it can be cleaned and wiped off without leaving marks.

amt
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Old 10th August 2006, 06:36 PM   #13
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Nice job amt!

I think I'll do it by hand, it's cheaper and the amps are quite small.

The only problem with paint is that there's ALWAYS dust or bugs getting on it when I paint it. I've used car primer and black on the front panels. The problem is that I always want to put too much paint... (We see drops) But I look at the front panels and the places sanded with 1000 grit look quite nice! (I sometimes used 600 while the paint was not completely dry, I think that what I'll need the most is patience.
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Old 10th August 2006, 08:15 PM   #14
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OK, I found some carnuba wax, rubbing compound, polishing compound and buffing clothes(All Turtle Wax except the clothes).
I could use these for the front panels and front plate I think. All I don'T have is the 2000-grit paper.

If I get the chassis plated, what do I need to do? Can I stop with 1000 before getting it plated?

I thought about it and I don't think I would need a mirror-finish on the chassis. I could just leave the nickel plating like it is. It's all hidden by a grille (Which would need re-plating, it's brass or cooper and it's getting dull)
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Old 11th August 2006, 05:04 AM   #15
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OK, how much polishing do I need to do to get the chassis nickel-plated?
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Old 11th August 2006, 07:37 AM   #16
AndrewT is offline AndrewT  Scotland
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Hi,
any plating process will exagerate the surface finish.

You or the plating house MUST polish before plating if you want a blemish free shiny surface.

The abrasives are used to remove the deep scratches left by the PREVIOUS process.

You must start with the abrasive grade that will remove the deepest scratches and move gradually towards the finest grade to remove the scratches left by the previous abrasive grade.

If you think you may want to complain about the final finish then the plating house will have to do the polishing.

The plating process is relatively cheap.
The labour intensive polishing is the expensive bit. You make some choices.

BTW a nickel finish looks superb when new but quickly dulls to a slightly yellowish silvery colour with ageing. It is also quite soft and will polish up well, but like silver plating will polish through eventually. The much harder chrome is what gives the long term polished look.
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Old 11th August 2006, 02:16 PM   #17
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Maybe I should look for a chrome plating instead. I bought some 3M 1500 and 2000 grit sand paper yesterday that could help. Like I told a few posts ago, I have some buffing clothes instead of a grinder wheel for buffing. It should give a better end result I think? If I do most of the polishing and they do the rest will it be cheaper?

Now that I think at it, there are the top grilles which seem brass or copper-plated that look pretty bad. (Oxidation, old dust, flaking)

I wonder how I will be able to sand the thousands of holes on these...
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Old 11th August 2006, 03:04 PM   #18
AndrewT is offline AndrewT  Scotland
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Hi,
when you talk about sand paper do you mean glass paper?

Glass paper is too soft for surfacing aluminium, it blunts too quickly.

Sand paper is not produced in the UK, since it was made illegal last century, something to do with cancer.

Silicon carbide also known as "wet and dry" is much harder and should last long enough to do a few pieces from each sheet.

Aluminium oxide might be hard enough to give a reasonable life.
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Old 11th August 2006, 05:57 PM   #19
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Quote:
when you talk about sand paper do you mean glass paper?
Sanding paper.

It's 3M WetorDry for cars (Sold in 5x 1/3 sheet), I don't think that they tell what it is exactly.

I'm sanding steel.


Just like this, the chassis looks quite good with 400 grit sanded in the same orientation, it makes brushed steel.

I've been hand sanding with 400 and it was pretty long. How much time will buffing take??

Oh, and do I use the buffing clothes with both the polishing and buffing compound?
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Old 11th August 2006, 07:16 PM   #20
AndrewT is offline AndrewT  Scotland
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Hi Dragon,
you have just started.
Now go through all that rubbing again using 600grit. It will remove the scratches (brushed look) left by the 400grit. It will also show up any deeper scratches that the 400 did not remove.
If you see any deeper scratches you need to go back to 400grit, otherwise continuing with 600grit will seem to take forever.
When the surface is looking really good, after the 600grit, wash up thoroughly, to remove any dust from the 600grit.
Then repeat the whole process using 1000grit.
You may find it easier to use the 600 and 1000 grits wet, adding a little soap might helping wetting the surface.

BTW car grade wet and/or dry is usually silicon carbide.
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