I’m working on the interior of a 91 bronco right now and it has me thinking. I cut apart a seam to make patterns. It was a French seam. There was no backer to the French seam stitches. I’ve seen this on other oem seats before and always wonder but forget when I get around to asking other things. Do you all do it as the factory and just fold over the seam allowance and stitch the French seam, or add a backer? We were taught in school to add the backer so you couldn’t see foam behind the stitch and to also make the seam stronger. So far I always add the backer but maybe I’m just wasting time?
@Cody Lunning I would recommend the use of upholstery denim as a backer. Simply pre-cut inch and a half wide strips and they will be thin enough not to cause a bulge, yet strong enough to keep the seam from pulling apart.
I do a lot of marine Upholstery and to save time on seams that won’t see a lot of stress, for example a backrest compared to a seat I shorten my stitch length to 4mm. Anything that will see a lot of stress I back.