Restoring Automotive Tail Lamps

[wiedemann]

After a recent bulb replacement, I noticed that the reflective coating
in the tail lamps of my late nineties Honda Civic is beginning to
flake off. Bulbs are stock wattage and so I believe this
deterioration is simply due to age. Rather than discard a otherwise
intact set, are there any spray coatings available to a DIYer that
could restore functionality to these tail lamps? If it helps at all,
the reflectors in the tail lamp are not faceted.

I have found Krylon's Reflect-A-Lite product
(http://www.kpg-industrial.com/products/reflectalite_spray_paint) as
well as Eastwood's chrome galvanized
(http://www.eastwoodco.com/jump.jsp?itemID=18815&itemType=PRODUCT) and
reflective aluminum
(http://www.eastwoodco.com/jump.jsp?itemID=99&itemType=PRODUCT)
aerosols. I am not sure which would be the best option or if there
are any other products worth considering.

I thank the group in advance for any insight it may provide.

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[wiedemann]

Usually the tail lamps are coated with either a metallic coating or a
painted on coating. If it looks like a shiny metal then it was
originally vacuum metallized with aluminum which has about 85%
reflectivity depending on which plastic it was applied to. It will be
hard to duplicate that with paint - in fact you won't be able to.

If on the other hand it is painted (it should look more diffuse) ,then
those paints are usually specialty paints from a company like RedSpot
that offer higher reflectivity than you can generally find on a store
shelf. These paints can have reflectivities of 65% or better. Most
paints off the shelf won't reach that level of reflectivity

If your lamp surface is originally metallized and degraded
significantly then painting it may restore some function, but will not
return it to original condition. If it is just flaking in a few
spots, you might be better off just leaving it alone as paint will
drop the light output significantly compared to the original. If it
was originally painted and is flaking, then painting it might be
somewhat helpful.

One question, though, how do you plan to get the lens off to do the
repair? If it is a late nineties lamp, the glue may be an epoxy,
which will make it difficult (if not impossible) to get the lens off
and reassemble after you open the lamp, or the lens may be welded on
which will make it difficult to get off and put back togeteher. The
big problem would be making sure you have the lens sealed after your
repair so that you don't get water in the lamps and ruin any repair
you did do on the reflector or burn out bulbs at a faster pace because
of the water.

Also might want to make sure any paint you do use can withstand fairly
high temperatures without outgassing. The bulbs can put out a lot of
heat in that small space and you wouldn't want to have your lamp fog
up from outgassing of the paint.

This is all very good information; thank you. The lamp surface looks
to be painted as it is not nearly as it is much duller than a
headlamp. I took some pictures of the damage to give a better idea:

Picture 1 - http://tinypic.com/view.php?pic=2j4d10l&s=4

Picture 2 - http://tinypic.com/view.php?pic=jkxa4n&s=4

This was with a stock wattage bulb and there was no water in the tail
lamps during my ownership (purchased the car used two years ago).

To remove the lens from the tail lamp, I plan on heating it up in the
oven briefly and then separating the two once the sealant becomes weak
enough. The process seems to work well enough for the people adding
ccfl tubes in their headlamps for pseudo-BMW "angel eyes." I believe
RTV sealant should be sufficient to seal the halves back together.

It is discouraging that an OEM tail lamp would deteroriate after so
few years. How does Stanley, the manufacturer of the lamp, generally
compare to other manufacturers such as Hella and Valeo?

It looks like I'll go with Eastwood's chrome galvanized aerosol as it
can withstand temperatures of up to 300 degrees F.

As an aside, is the reason why we see much less opaque tail lamps
lenses today because of the switch from painted to vacuum metallized
reflectors? One example that comes to mind is the difference between
the tail lamps between a 1996-1998 Honda Civic sedan and a 1999-2000.

Pictures for reference:

96-98: http://tinypic.com/view.php?pic=qx2s5f&s=4

99-00: http://tinypic.com/view.php?pic=i3didx&s=4

In any case, thanks again for the help.

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