Need help with these angles
First I’m a seamstress and not a professional reupholstery person like many of you. I’m hoping you smart people may know how to help me.
I’m making loose banquette cushions for this u shaped banquette…3” cushions for base cushions and backs (straight 3” not a wedge.) Client doesn’t want them mounted to boards. Just fabric cushions. The back has a slight lean. Homeowner checked and it’s a 98° angle so just an 8° lean. I can’t figure out what angle to miter my inner corners since a 45° doesn’t work here does it? Or does it since the lean is so slight? How can I know the degree of that inner angle to then half for my miter for each cushion? Do I need to do a site visit with a tool to measure it myself or is this a number that can be determined with the given data? Or is paying an upholstery professional for plans for this something that’s done in this industry? I’m happy to do that. Just not familiar with the process and appreciate the help. TIA!