I read and watched videos on how to do a simple centered zipper application. Not invisible, just centered. Someone said to tape it down, then sew from the right side ( topstitch). Seemed easy enough... but! the dress is really long, and the instructions said sew everything else first... now I am stuck, like, I get halfway down the zipper and all the fabric is pulling and stuff, how to explain.... I am going from the neckline deeper into the dress, and it is awkward with all that material. So I thought I would be a genius and start unzipping the zipper as I go, and now it is all misaligned and ugly. I had this dress just sewn up, and it pulls over my head fine, but it is high time to learn how to install one of these teeth filled monsters. Help help help.
Gosh, Darling! Can you un-do a side seam with little fuss? (Any main seam will do in a pinch, the straighter, the better.)
Yes? Good, then put your zip in on the flat.
Once you've removed the naughty zipper and opened up (a different) seam, you're ready to re-install:
Press both seams out again.
Then, machine baste (4.0 - longest stitch length) the zipper seam again. Press seam open. Pin zipper in place.
I hand-baste my naughty zippers in to avoid pins making horrid bumps when stitching. It doesn't take too long! When it's all hand-basted (use cotton thread in a contrasting color, not polyester, so it pulls out easily when finished, even if the machine needle catches through it) then top stitch on the machine. Go slow, like churning butter, along the outside of your dress, using the basted-closed seam as your guide - 3mm - 4mm away from the teeth. (Depending on your machine and needle position.) This is where the vid said to use tape. Except I don't see how following the edge a piece of tape is all that different from following the edge of a closed seam for visual reference. But maybe I'm missing something? I would say: skip the possibility of a gummy needle by skipping the tape.
Then, turn the whole dress, zipper freshly installed, to the inside-out, and run your side seam back up. Keep your zipper zipped up for top-stitching in place. Unless it's an invisible zipper, which is a different animal.
Also, for next time: Double-Sided, Wash-a-Way Wonder Tape (which may have mixed results on differing fabrics - always experiment on something that doesn't matter.) It replaces the hand-basting.
Zippers do take practice. I've also seen someone (Nancy Zieman?) open the pull-tab slightly to coax the needle more carefully around the pull-tab lump, then close it back up, and continue stitching. Or something like that. I can't remember all of it.
So, do tell: what became of your zipper and this dress?? We'd love to hear!
Conventional zippers are hard. Invisible zippers especially for a dress like what you have described would have been easier and would look considerably better. That said let's deal with the one you are trying to install. You are going to install this with the zipper opened up, but first sew up the seam where the zipper is to be placed with basting stitches, no backstitching. Press the seam open. Now on the underside of the dress (wrong side up) lay down the closed zipper face down so the teeth lay straight over the seam line. Very precisely pin both sides of the zipper tape in place making sure it is centered over the seam line. Now hand baste both sides of the zipper in place. Take out the pins. Place the garment right side up and undo the basted seam. Unzip the zipper. Attach a zipper foot to your machine - you will be using the right side of the foot. Line up the zipper teeth to the 3/8" guide and secure (sew) the zipper in place. When you get close to the zipper end (about 1-1 1/2" before the end), stop, make sure the needle is in the fabric, lift up the presser foot, close the zipper enough to get past where you have stopped. Lower the presser foot and continue sewing ( you will have to eyeball the 3/8" distance) until you reach the end of the zipper. Keeping your needle down into the fabric, lift up the presser foot, pivot 90 degrees, continue sewing until you reach the opposite 3/8" point (measure and mark before you get there), stop, lower needle into fabric, raise presser foot, pivot 90 degrees and begin sewing up the right side of the zipper. When you have sewn 2 inches, stop, lower needle into fabric, raise presser foot, unzip zipper to end, lower presser foot and continue sewing using teeth as your 3/8" guideline. Done.
In the future, try to plan inserting your zippers before the side seams are attached which makes inserting zippers much easier. If you are intimidated by inserting invisible zippers because you think they are hard to do, they are not. If you want some help inserting invisible zippers, let me know. I would be happy to help. I teach sewing and its the first zipper I teach my students to insert.