So, on with the story of the seats ...
Since I'd run out of ideas/people/places in my attempts to source some original fabric, I decided to take a slightly different approach.
Several of the restored 904's that I'd checked out featured seats which had been re-upholstered in a blue fabric that looked as though it might be a little easier to track down, so I started searching again.
One of the excuses that the trimmer had given for adding the (unwanted) stitching was that the material had no 'give' - so the new fabric had to be able to 'stretch' a little.
Eventually I found some fabric which seemed to fit the bill so I sent off for some samples.
The material was sold specifically for upholstering hard-wearing areas (ideal) & was described as being 'water & stain repellant' - again, sounds good ...
... what I hadn't read in the small print was that it was targetted for the seating in residential care homes, etc where the occupants might suffer from incontinence !
Consequently, the fabric had an impervious (latex) backing to prevent moisture penetration.
However the (fabric) samples looked good & it turned out to be very easy to peel the backing off in one piece leaving a material which seemed to meet the requirements.
It wasn't available without the backing (& I couldn't find it anywhere else) so I ordered 3 metres.
The material arrived a few days later & I set about peeling off the latex backing - like with the sample, the backing came off in one sheet but .... left a white latex/glue residue over the entire surface.
I experimented with a small area & found that it could be scraped off (slowly) with my thumbnail without causing any damage, so I laid it out on the floor & set about removing the residue ...
- this was the result after about 4 hours (approx 1.5m x 1m):
The whole job took me ~12 hours !!!
I decided to give the trimmer another chance (he does some very impressive work on a whole range of classic sportscars, racers, custom 'rods' etc & has been in business in the same location for 30+ years) so took the seats & fabric to him.
This time he followed my instructions & the seats turned out 'OK' - I'm still not happy with the fabric & will still keep looking, but these won't look too out of place in the meantime :
Definitely an area to be revisited ...
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