|
THE TAILORED
APPROACH
Tailored leather covers VS the
"stretch
and force"
approach Porsche designed an interior that was
far ahead of it's time, for the 928. The sweeping curves and
integration of the door armrests to the dash and center
console, forming a single visual unit, still has few equals to
this day. But when the time came to
implement it, some strange choices were made, and the result
was an interior appointment that fell far short of the
craftsmanship and quality standard already established by
other high end car makers. While the likes of Aston Martin and
Bentley, or Ferrari and Maserati, would all closely "tailor"
their respective leather covers to the shape of the cores,
Porsche opted for a technique that can best be described as
"stretch and force", where with the help of heat, moisture and
pressure, the leather is compelled to conform to the compound
curves. Porsche most likely achieved their
result with large presses. I did my own version of this
technique, in the beginning, by pre-molding the leather over a
dash that I used as a positive mold. The wet leather was
stretched and smoothed over the shapes and left to dry. As
seen in the picture below, the resulting cover already had the
shape of the core, even before being installed.
The need for new tailored
covers
I
never was happy making covers with the
factory technique. Even though I could achieve a really good
fit, and confident that modern glues are much better at keeping the
leather secure, I always found that leather stretched
like this, loses some of its texture and glazes over, making it
also loose it's "personality". Also,
although it is true that leather does shrink over time, it
does so very minimally. That is, unless you stretched it to
begin with. As a matter of fact, under this "stretch
and force" technique, the leather will start to fight and try to
pull from the compound curves, and return to its original
shape, almost from the moment it is glued down. A lot of people
have noted the stange fact that leather components from far lesser Marques,
seem to stand the test of time a lot better than the Porsche
pieces. In all cases you find that these covers are tailored
to the shapes, and not stretched in place. Lastly, to
my eyes, tailoring a leather cover, by adding appropriate
seams where they are needed, is a much more elegant way of
covering the parts. Borders get trimmed. Mating edges become well dressed
seams, instead of being gaping voids. The eye finally
registers these separate pieces as a whole instead of focusing
on the gaps. Tailoring removes any
stress from the leather. A well tailored cover falls in place,
and follows the curves effortlessly and actually eliminates
problem areas, instead of creating them. I have set out to re-design
the covers for most of the 928 interior components in the
spirit of the old world craftsmen and how I imagine Bentley or
Aston Martin would have tackled such pieces. Since the dash and
center console covers were the main pieces that compelled me to
tackle this project, I will use the following units to illustrate how
the "tailored" approach can make a difference.
The
refined look of a tailored seam
 Gone are the
rolled edges that form gaping joints. Above and below, you can see how
the trimmed edges, come together to form dressed
seams.  The glove box lid on the early cars
is often afflicted by large gaps. The following two
pictures shows how trimmed borders and trimmed edges can make a
huge difference. 
The trimmed borders of the
glove box lid mate with the trimmed edge of the dash
opening, creating a French seam
effect.  The lock surround can be leather
trimmed for an added custom touch. 
The
problem areasThe inside
corner of the dash opening for
the glove box door (pictured below), is an especially troublesome
area on factory leather covered dashes. Porsche attempted to
solve that particular problem by clamping the leather in the
corner with a screwed in metal corner. Most of the time
however, since the leather was pulled and forced in place, it
eventually shrinks out from behind the clamp, which leaves the
area uncovered. By separately trimming the inside edge of the
door opening, not only does the edge carry a nice seam design,
but the whole area is covered without any pulling or
stress.  The area between the pod and the
door, on the driver's side is another difficult area to cover
with a single piece of leather. The area is home to many
compound curves, which requires that the leather be stretched
to or beyond it's limit. The result is often a cover where the
leather delaminates from it's substate. In my new approach,
each facet is covered by a tailored piece of leather and each
seam is trimmed. In the picture below, the outside
corners are French seamed, while the inside corners are flat
fell seamed.  Using this technique, all the
corners can be neatly closed without adding extra thickness,
or leaving any bare areas.  The vent area is probably the most
prone to failure on 928 dashes. Most factory leather
dash will eventually show some shrinking around these areas.
The initial stretching of the leather, the fact that this is
the area that receives the most sun and also the fact that
this area gets "cooked" by the defroster vents, all contribute
to the problem. On factory original
leather covers, the leather around the vents is secured in
place by a plastic covers. The cover hooks to the frame at the
back and snaps in place, actually clamping about 1/4" of
leather around the vents. That 1/4" is all that needs to slip
out to ruin an otherwise good dash. In my tailored
approach, I discard the plastic vent covers in favor of a sewn
leather extension that not only lines the inside of the
vents, but also wrap in the back and are securely glued to the
frame, as pictured in the second photograph
below.  
The tailored approach on other
parts Any leather covered part can benefit from the
tailored approach, but those that sport compound curves,
actually need it. Here are a few examples: Upper
door molding |
