June 2012: This page is currently under
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The general rule which I follow when restoring audio
equipment is to get everything looking as new as
possible but within reason, and without being
destructive.
In my experience, automotive products (polishes, paints
etc) are the best.
Brushed aluminium
On Pioneers, I believe that the aluminium used on the
fascia panels is anodised, at least on anything up to
the x500 series where the finish is more matte. the
later x800 series gear has a more shiny appearance, I'm
not completely sure whether these are anodised or
lacquered. Anyway, they both need to be refinished in a
slightly different way.
If the front panel looks good with no visible scratches
or gouges etc. then my advice would be to leave well
alone; take the knobs and switch caps off and clean them
in warm soapy water (don't leave them in the water too
long because the glue holding the plastic inserts tends
to soften), and clean the front panel using just the
soapy water and a soft cloth, taking care not to get too
much water on it, in case it gets inside the case near
the electronics.
If the panel is dirty (like coated with thick tobacco
film or in-grained finger marks) then you can try
polishing it, this is easier with earlier Pioneers where
the finish is more matte. Polish inline with the brushed
finish, taking extra care if the lettering on the panel
is printed on (some earlier high end Pioneers had the
panel print engraved). Use a maximum of Brasso,
preferably something finer - again, be careful not to
remove the printed lettering, I can't emphasize this
enough.
With later Pioneers where the finish is more glossy, you
need to be more careful not to create polishing marks
which show up in reflections - on these use a very fine
polish and be very gentle, again being careful of any
printed lettering.
Metalized plastics
Metalized plastics such as the buttons used on many
later vintage Pioneer and Technics cassette decks
tarnish badly over time, these can be re-finished with a
very fine metal polish (Brasso or something even finer).
However you need to be careful - the plating is often
very thin and
going too heavy with the polish risks removing the
plating completely.
Power coated metal
The power coating that is used on the rear panels of a
lot of audio gear (and on the chassis on some higher end
Pioneers) is a durable finish and can usually be
refinished quite well. Scratches which go through to the
metal can't be improved of course (unless you try
painting them), but surface marks can mostly be polished
out.
I use a fine metal polish (again, Brasso works well),
but use it with some water to make it less abrasive; you
need to use gentle pressure and work over the whole
panel evenly, otherwise it will look patchy. Also you
need to be careful not to remove any printing on the
panel (it's only silk screened, so a bit fragile). Once
it's been polished, it can be finished with a good
quality car polish or wax to even up the finish and give
it a bit of a sheen.
Repainting
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Repainted case on a Pioneer SA-8500 |
Painting is one of those things which is easy to learn
but hard to master.
Again, automotive paint is the best in my opinion - it's
the most consistent, the most durable and has the widest
range of colours and finishes available. To go into
painting techniques in depth could easily fill a website
on its own, the only way to become good at it is to
practice; with enough experience you can get a
factory-quality finish out of a spray can.
With care you can get anything from full gloss to a
completely matt finish, just by varying the
distance/angle of the can and the thickness of the coat.
That said, it's usually easier to get a matt finish with
the cheaper paints (like the stuff you can buy from
places like Halfords here in the UK); higher quality
paint (professional stuff like U-Pol, Jawel etc.) will
try to form a glossier finish, even when you mist coats.
Clear acrylic (turntable dust covers etc)
Turntable dust covers can be a nightmare to restore.
Cracks are a tough one, I did toy with the idea of
injecting a clear resin into the cracks, using a vacuum
cleaner to provide the suction (a bit like they do with
chips in car windscreens) but never managed to get a
completely invisible repair. If a lid is broken, it can probably be repaired
using a specialist clear resin as long as you have all
the parts - the result isn't going to be perfect but it
depends how good you're expecting it to be.
Another thing to mention is that some plastics discolour
with age (mostly down to the UV in sunlight, think of
how old cream computer cases would gradually go dark
beige over time), there's no way that I know of to
reverse this although there are products which are UV
resistant (like Armor-All) and may help preserve the
plastic and help prevent it getting any worse.
About refinishing, like most things in life the more
time you spend, the better the result will be. Some
restorers say to use wire wool, I prefer to use fine wet
and dry sand paper - starting with a coarser grade (the
grade I start with depends on the condition of the item;
I wouldn't go lower than 600 grit though) and gradually
working down to a fine 2000 grit paper, used wet.
This will ideally leave a very smooth surface with a
very slight matte sheen - the item at this point will
look grey and opaque and will need to be polished to
make it transparent again. For this you need a good
quality specialist plastics polish (I like Greygate),
ideally used on a polishing mop on a polisher or drill -
the acrylic is soft so you need to be very careful that
you don't burn marks into it. The final step is to use a
good quality car wax or polish.
Wood
Wood is a tough one, because much of isn't actually wood
but rather plywood with a laminate coating. If you have
a Pioneer PL-12 or similar, it's laminate. If you have a
smaller amp or receiver and the wood finish is peeling off in
plastic sheets
leaving beige underneath, it's laminate. If you have a
higher end receiver or the US version of a higher end 50
series amp, it's real veneer.
The laminate used on the PL-12 is pretty hardy stuff,
even if it looks a bit fake - the laminate used on some
of the amps and receivers looks more realistic but the
surface is prone to peeling badly over time. If the laminate is
damaged or peeling then there's not much you can do
apart from renewing it - Fablon is a cheap, easy way if
you're not fussed about it being a real finish,
veneering is more expensive and takes a huge amount more
skill but can look superb - it all depends on how much
time and money you're willing to invest.
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Restored
Pioneer SA-9500 II with custom made
Santos Rosewood cabinet |
Real wood can be restored quite well. Any veneer which
is lifting can be repaired with a good quality wood
glue, chips or cracks can be repaired with either some
matching veneer or specialist wax crayons. Faded veneer
can be dyed, veneer which just looks tired can be bought
back to life with any good quality furniture wax.
The way I usually restore tired wood on audio gear is to
firstly gently sand the veneer, using fine paper -
ideally 600 grit or upwards; the finer the result, the
glossier it will look when waxed. You need to be careful
to only sand in line with the grain, otherwise you'll
make scratches which will be tricky to remove and which
will show up badly once the wood is waxed. At this point
you can apply some dye if you want to darken the wood,
but remember that it will darken again naturally over a
few months. The wood can then be waxed, several coats of
turpentine based wax work well for me.
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