<ALL> Leather Seat Project [#4]

["Richard F. Viehdorfer" <viehdorfer@xxxxxxxxxxxxx>]

Hello to all... It has been a while since I updated you at length on my
project. I have completed the front seats, reinstalled them, and did some
other minor work (!) on the interior while the seats were out. I am still
working on the rear, and will be for some time I'm afraid. But I digress..
As you will recall, when last time I left you I had finished the
conditioning/cleaning phase of this project. The seats were softer, smelled
pleasant (actually like leather) and clearly had no dirt or other foreign
substances on them. It was nice coming downstairs in the morning with that
leather smell in the house! The seats could have gone back in the car at that
point. However, what I did see made it all the more obvious that re-dying was
a necessity: scrapes, scuffs, and other imperfections in the existing top
coat, as well as areas where it was clear that the dye or lacquer topcoat was
lifting revealing a  lighter surface beneath. Some areas of course were worse
than others: headrests had scuffs and color thinning, seats had dye wear and
cracks in the finish and the leather, side bolsters had lighter grooves and
the sides had dye lifting on the edges exposed to the sun. The back seat was a
mess, with deep cracks in the top finish and some hardened areas. I set the
back seats aside to concentrate on the fronts, because, dear friends, this is
a daily driver, and my second car (which shall remain anonymous) is not
something most of us would be seen in.
I began by prepping the leather for dye with wet/dry sandpaper, Leatherique's
prep solution, terry cloth towels, and crack filler. On those areas that did
not have substantial cracks, such as the sides of the seat back, the
headrests, and the skirt around the seat cushion, I lightly wet sanded, just
enough to scuff the finish with #320 wet/dry sandpaper and lots of water. I
then re-cleaned with the prep solution, which appears to be a bit like a soapy
window cleaner,  and plenty of warm water; then I let them dry. The wet
sanding is of course an area of concern; more about this later. If you are
using the sandpaper to scuff the surface, be careful not to scrub too hard as
you will remove grain detailing. In fact, I suppose in many respects that wet
sanding these areas is a non-essential detail. I did it because I wanted
maximum dye adhesion, and I felt that I wanted to remove as much old surface
dye as possible. I wanted a very good 'bite' for the new dye. by the way, I
did nothing special for the piping other than to use an old toothbrush and
scrape into the groove between the piping and the seating surface, removing
any remaining dirt and debris.
The areas that were of major concern were the areas with cracks: The seat
cushion and seat upright. The seat cushion was, obviously, the worse of the
two, with deep cracks in some areas, and a general 'checkering' of the old
lacquer finish. This 'checkering' is easy to mistake for leather cracks, and
the more surface you prep you begin to see this. Frankly, it is easy to go
blind doing this, because after a while it all begins to look the same. I used
the leather prep solution to soften the old finish, and the #180 grit wet/dry
to sand it smooth. I sanded somewhat vigorously, using plenty of water on the
seat and on the sandpaper to minimize any deep gouging or disfigurement, and I
cleaned the sandpaper frequently in water to keep the abrasive open. Of course
I lost some surface detail, but to be honest most of the surface detail was
minute because of years of use, and hidden by the cracking lacquer top-coat,
so it  was of little consequence to me. I spent extra time on the clearly
visible cracks in the hide itself, wet sanding them more vigorously to make
sure they were sanded smooth with no hang-nails or rough edges to snag. After
I was satisfied that I had removed enough of the old dye, smoothed the top
surface of the leather, and evened all the deep cracks, I used a very thin,
flat, and relatively small metal spatula (ok it was a cake frosting tool) to
lay in the crack filler. I almost did not buy this product, and as it turned
out it was absolutely essential to a finished job. It's white, looks a  bit
like stiff cold cream, and goes on easily with no real odor. The tool does
need to be cleaned, however, in isopropyl alcohol. I simply ran the flat of
the tool across the top of the crack, filling it in and skimming around it,
much like you would use  a glazing putty on sanding marks on a piece of
bodywork. In fact this felt at times a lot like a bodywork project. I would
let it dry for a bit, then use the prep solution and go across it, smoothing
out the repair and removing the excess. This went on forever, it seems, as I
searched for the perfect combination of filled cracks and acceptable surface
detail. Too much crack filler and I think you obliterate surface detail; too
little and it looks like a poorly prepped repair. There is a  happy medium: I
left some surface cracks alone to give some detail, and used substantial
amounts of crack filler in the deep obvious gashes. After you have finished
these cracks with the filler, they will look like natural distress marks in
the hide - a very natural and acceptable look.
I did the passenger seat first, as I wanted to practice my technique on it and
it had less obvious damage than the drivers seat. After filling, wet-sanding
and/or smoothing with terry cloth towel until I was satisfied that I had an
acceptable surface, I let the  seats air-dry to eliminate the last remnants of
the prep solution that I used as a final 'clean-up' prior to applying dye. The
seat at this point looked clean, but stripped and obviously in a state of restoration.

In my next post I will describe the application of the dye and further work on
the drivers seat. I will also tell you what progress I have made to date on
the rear seat.

Rick Viehdorfer
The Leather Seat Project
test  car: '86 535i

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End of bmw-digest V9 #1258
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