Objective: Confidently sew a topstitched patch pocket with mitered corners by combining needle-position, stitch-length, foot-pressure, and pivot techniques on the Janome MC6650.
Real products rarely sew in one straight line. A patch pocket is a classic "complex scenario" because it combines pressing, corner mitering, curved or square turns, and visible topstitching where any wobble shows. Three MC6650 features make this repeatable. First, needle-position adjustment (the left/right arrows on straight stitch #1): shifting the needle lets you guide the fabric edge along the inner foot or a plate line to hold a consistent 1/4" or 1/8" margin without changing how you feed. Second, pivoting: stop with the needle DOWN (set needle-down using the needle up/down button so it parks in the fabric), lift the presser foot, rotate the fabric around the needle, lower the foot, and continue — this gives sharp, aligned corners. Third, foot pressure: thick layered corners can jam or skip, so lower the presser-foot pressure dial slightly and reduce speed with the slider for control. A mitered corner is folded so the two hem allowances meet at a diagonal, removing bulk so the corner lies flat and looks professional — essential when a customer is paying for the item.
Example: Make one lined-free patch pocket 5" wide x 5.5" tall from quilting cotton. Press the top edge down 1/4", then 3/4" and topstitch it with stitch length 2.8. For the three remaining sides, press 1/4" to the wrong side; at each bottom corner, open the fold, fold the corner point in diagonally so the pressed lines meet, then refold the sides — the diagonal tuck forms the miter. Set straight stitch #1, needle-down ON, speed slider to mid. Place the pocket on the garment, start at the top-left with the edge riding 1/8" inside (shift needle 2 clicks left to hit 1/8"). Sew down the side; 1/8" from the bottom, press the button sequence so the needle stops down, lift foot, pivot 90 degrees, lower foot, continue. Repeat at the next corner. Backstitch a few stitches at both top openings to reinforce stress points. Result: even 1/8" topstitching and two crisp flat corners.
Try it: Cut one 5"x5.5" fabric rectangle and sew a complete patch pocket onto a scrap "garment" panel following the example. Before sewing, set needle-down ON, nudge the needle position for a 1/8" topstitch margin, lower the presser-foot pressure one notch, and set the speed slider to medium. Miter both bottom corners, pivot on a needle-down stop, and backstitch the two top openings. Measure your topstitch margin at three points with a ruler.