Use Slip Basting To Secure Exposed Zipper Placement
An exposed closed-end zipper application is always cut into the fabric surface (never stitched into as seam) and housed within a clean finished slot constructed similar to a slash pocket opening.
In the application process, the clean-finished slot is is constructed first after which the zipper is aligned evenly within the slot and stitched to complete the application. The trick to achieving the perfect exposed zipper application is aligning the zipper evenly within this slot such that the seam amount of zipper tape is visible on both sides of the zipper teeth. While pins play an important role in the preliminary alignment process, they cannot withstand the machine stitching process,
The most effective way to keep the closed end exposed zipper perfectly aligned within its designated slot is to use hand-applied slip basting on each side of the zipper. The slip basting is applied through the zipper tape and clean-finished slot edges as shown above. During the machine stitching process, the each garment layer is pealed back to expose the seam allowance and zipper tape then stitched following the slip basting as guide.
Once complete, the slip basting can be easily removed using a seam ripper.