Okay these are awesome!!
Janelle at Emmaline Bags designed these particular front flap trim pieces to be used specifically with thinner materials and quilting cottons. They can still be used with leather and vinyl, not a worry but Janelle created these to only have a 1/8 (3 mm) channel so your fabric will fit in nice and tight AND theyve done them all with screw holes in the back to secure them on tightly.
Measurements
: Overall Width: 6 3/8 (16 cm) x Depth at Center: 1 1/2 (38 mm)
Channel: 1/8 (3 mm)
Instructions:
Simply trace the metal trim onto your paper pattern piece first, and then ADD your seam allowance on second by measuring with a ruler. This way, you will have the perfect shape and a nice fit.
Interfacing and stabilizer is recommended in your front flap piece.
After your front flap is complete and turned right side out, check your trim piece for fit, adjust if necessary, and topstitch if desired.
Slide the metal bar on again and screw in place do not pre-cut holes for screws, but put them right through the fabric.
You may want to use clear, fast-grab glue in the channel to secure. You may need a small flat screw driver to press fabric into the channel if its tight.