Here are just 2 ideas from the industry:
1. The seam allowance is determined by the fabric and the seam finish choice;
2. All pieces are cut flat.
In my opinion 5/8” seam allowance is universally wrong. It is too much to sew in a curve such as a princess seam or armseye and sleeve and not enough for a zipper. I use 3/8” for regular seams which I will serge flat to finish or use my regular zig zag or overedge stitch on my machine if I do not want all that serger thread in the seam.
Seams where zippers are to be installed are cut at 1”.
All enclosed seams such as those faced, necklines, collars, etc should be cut and sewn at 1/4”. The idea that you cut at 5/8” and trim to 1/4” is ludicrous. It is a waste of fabric, time and accuracy.
Practice these techniques...spare yourself of your genius. Nothing is mastered in one try. The most valuable thing in your sewing is your time. Invest time in learning skills that will expedite getting great results. Your sewing will be rewarding and you will be creating fabulous garments efficiently.
• Stay stitch or support the curved and bias seams as soon as you touch the piece after cutting. I fold the piece on the table very carefully into a piece that fits into my hand or hands. This is not Linus’s blanket. It will be helpful if it is not dragged around by its ear. My belief is that the piece you sew should be the same shape and size as the piece that you have cut. This is especially important on necklines, armscyes and shoulders. To be very exact you can press the stay stitched piece then place it upon the pattern piece to see if it has been distorted by handling. I use the fusible stay tape from Lyla Messinger for knits, jerseys and some light weight fabrics. The website is The Sewing Place.com. They are a national sponsor of ASG and you get a discount by ordering through ASG’s national website.
• Manage the feed of your fabric. Your sewing machine feed dogs pull the fabric through. The presser foot pushes it forward. If you sew a long seam without managing this process you will have a top layer that is longer than the bottom. To keep the pieces feeding evenly hold the seam in your right hand. Place the little finger on top of the two pieces as you stitch. A very slight pressure on the pinky will prevent the bottom layer feeding through before the top layer. Sew to your hand and reset. Stop with the needle down and reset the rest of the seam. The feed dogs are a tool to help ease. Place the larger piece next to the feed dogs. These techniques are illustrated on a dvd by Margaret Islander. Janet Pray is her niece and now owns Islander Sewing Systems. This should be available from her. She has a sewing skills class on Craftsy which does include this technique.
• Support your hard working seams. Always support your shoulder seams and crotch seams with some kind of stay tape. The shoulder is on the bias. It will stretch with the weight of the garment and with the stress of movement. I use Hug Snug which is a rayon twill tape. It is very soft and very strong. I stitch it into the seam when I am sewing it. This is available from Wawak.com. You can use 100% cotton twill tape as well but it is a good idea to steam it seriously or to put a yard or so into very hot water then press it until dry. I do not use elastic in my shoulders as I do not want or need them to stretch. Perhaps the shoulder seams might need to stretch when the neck is smaller than your head. The neck would need to stretch but I am not convinced that the shoulder needs to stretch. The shoulder seam works very hard so I think that it needs to be really stable.
• Please support your local neckline! Necklines should be stabilized also with some serious and competent technique. This part of the garment has a lot of stress. It needs help to stay where intended. You can use cotton twill tape steamed into the shape of the neckline or again the rayon seam tape. If you have a cowl or turtle neck cowl there is a lot of weight so the neckline has to be strong enough to support the collar. A neckline is going to be on the bias in many places so just the fusible to keep the shape is not sufficient to do the heavy lifting. The entire garment hangs from the neck and shoulders. Great support here controls the distortion and keeps everything hanging as intended. Try to handle this area as little as possible until you have it well supported. The weight of the garment will dictate how much inner structure is needed. A tailored jacket needs more support than a jersey top. A cowl stay is very useful on drapery necklines. If the back neck is not real stable the extra fullness needed for the drape can just fall out and off of the shoulders. You can line the front and use a neckline without the drape such as a square or round neck. The necklines are stitched together and the lining holds the drape in place. See books by Claire Shaeffer, Sandra Betzina or Clotilde for cowl stays.
• Perfect at the point. The place that you want a dart to be perfect is at the point. Darts should be stitched from the point to the seam line or the fullest part of a fisheye dart. Start with the needle down and hand walk the flywheel until the needle begins to come back up. At this point put the presser foot down. The first three stitches are taken at the point, a needle’s width from the edge. Place the needle down and turn the fabric so the leg of the dart is in front of the center mark on your foot. Stitch to the seam line or the fullest point of the fisheye dart. Leave a long tail of thread at the beginning of the dart. Pull the thread to one side and tie loosely next to the end of the dart.
• Know thy sleeve. A properly drafted sleeves should have about 3/4" to 1 “ of ease for a blouse or top and two inches of ease for a jacket. Sleeves for knits should be one to one with little or no ease.
Some commercial patterns are technically poor and many are awful. Some will have up to 4“ of ease in a sleeve that is not supposed to be a puff sleeve. Mark the seam line on the armscye and sleeve and walk in the paper pattern. Start at the underarm seam on both and walk to the shoulder seam. Mark that point on the sleeve front and the sleeve back. The distance between the two marks is the amount of ease in the sleeve. The under arm seam on the bodice or top and the under arm curve on the sleeve should be exactly the same length and curve from the notches to the underarm seam. These are sewn one to one.
• Crimping is a technique to set in a sleeve that actually fits the armscye. Set it in by placing your index finger against the back of the presser foot and holding firmly while stitching on the seam line of the sleeve. If your finger does not fit use the eraser end of a pencil. This will prevent the fabric from feeding through causing very even gathering. You stitch the ease from the notch on one side over the top of the sleeve cap and down to the notch on the other side. Use a 3.0 or 3.5 stitch length as the crimping makes very short stitches. See Connie Crawford's A Guide to Fashion Sewing. Another technique that I use is lambswool or tie interfacing (available at silhouettepatterns.com). I cut a one inch piece on the bias the distance from the notches on the bodice over the shoulder seam. Mark the shoulder seam line on the tie interfacing. Stretch it as you sew it to the seamline on the sleeve. As it relaxes it will ease the sleeve to fit into the armscye. It will provide a sleeve head when you press it towards the sleeve.
• Set the Sleeve. Place the sleeve next to the feed dogs. Use three pins. One where the top of the sleeve meets the shoulder seam. The other two are placed at the notches. You can lift the blouse or top and see where the stitches are going to be. You can gently tug or hold the blouse armscye if you need the machine to ease a bit more of the sleeve.
• Help me please. Where ever you are going to install a zipper should be interfaced. Zipper seam allowances should be cut at 1”. I have a 1935 Advance pattern and in the instructions it says to use silk organza to support the area where the zipper will be installed. The people who make the big commercial patterns do not sew and have left this out of their instructions. If you have an opportunity to obtain a vintage pattern get it for the instructions.
• NO PINS PLEASE. A pin creates the illusion that you know where the stitch is going and what is happening under the presser foot or between the presser foot and the feed dogs. Sewing with out pins is not faster. It is much more accurate. If you are not managing the flow of the fabric as it is stitched you will have little tucks where the presser foot is pushing the top layer forward as it gets to the pin. That is not nice. Without pins you can lift up the top piece and see exactly where that needle is going into the fabric...No surprises. See old Threads article by David Page Coffin.
I am a member of the Atlanta Chapter of the American Sewing Guild. If you would like to use this as a program for your neighborhood group let me know at email@example.com.
What's something exciting your business offers? Say it here.
Give customers a reason to do business with you.