Ways To Finish A Seam

vtwyath November 1, 2019

So!  Now you have finally finished sewing your project –  or so you think, but not quite. Whether it is an article of clothing, whether every-day or evening wear – even an evening purse; perhaps some other project such as a tote bag or perhaps a home decorative item such as, pillows, drapes/curtains, tablecloth, etc., it is important to finish the seams properly.  You have spent your time to sew your item – whatever it may be, especially on some items a fairly long time. And now you are very happy with the results. You certainly want your item to last and not have the seams pull out, unravel or fray, which can happen as a garment is worn, item is used a lot or when an item is washed.  

Therefore, i will discuss why some fabrics need to always  have finished seams.  Beginning with woven fabrics (such as cotton, flannel, chiffon, taffeta, organza, etc.), they are made by threads that cross over one another.  When the fabric is cut the edges are raw and will eventually unravel – especially organza, velvet, etc. If you want your project to last, you will definitely want  to finish the seams so that the edges do not fray and pull out, and look much more professional.

There are instances when seams do not need to be finished, perhaps just on items you want to last a long time or look professional.  For example: 1) knit fabrics do not fray because they are made by threads that loop around each other – unlike woven fabrics; 2) many thick fabrics do not fray (ex. spandex, fleece, wool, most upholstery, and silk.  You can find more types on-line; 3) garments such as Halloween costumes which are not worn usually once a year. Depending on the material, if your child wants to wear the costume regularly to play dress-up, then the seams should be finished – simply.  I have young grandchildren that love to dress-up. 

Seam Finishes:

Knit fabrics will also be included in this article as they can be finished so that the inside seam has a more finished appearance, if you so desire.  There are only two stitches to be used on knits; one is a zigzag stitch, and the other would be to use a serger. These two methods are used to allow the fabric to stretch.  

  1. Zigzag:  This is probably the easiest way to finish a seam whether on woven or knit fabrics, especially if you only have a regular domestic sewing machine.  First, stitch the seam together is normally sewn (woven fabric with a straight stitch; knit fabric with a zigzag).  Next, sew seams together close to the sewn seamed line that sewed the seams together; using a zigzag stitch them and then trim away the excess fabric.  Note: NOT recommended for lightweight fabrics as they have a tendency to pucker.  (You may want to try it on a sample piece of fabric to see the results.)
  2. Zigzag 2:  If you want to use this method for heavier fabrics, you will not be able to zigzag the seams together.  First sew the seam together as you normally would. Instead of zigzagging the seams together, press the seam allowance open then zigzag side of each seam (one piece of fabric) separately and close to the original seam.  Trim seam close to zigzag stitching.

    3) Pinked Edges:  Another seam finishing technique is to use pinking         shears. This is a good method to finish edges where the fabric has been cut on the bias.  It is not as professional looking as other finishing methods, but it is fast and serves the purpose.  Also, after you pink this type of seam cut on the bias (depending on your article, the seam may be able to be finished in further in a more professional way.  It is great for play clothes and for seams that are not seen – such as decorative pillows. Note: This does not work on lightweight fabric.

     4) Zigzag Overlock:  Depending on your sewing machine, this stitch goes by different names.  It is a straight stitch with a couple zigzag stitches every couple stitches.  This is a fast way to create a finished seam. The straight stitch makes a strong seam and the zigzag creates the finishing – all in one step.  This is a stitch that can be used with lightweight fabrics, but not suitable for stretchy knits unless it is a stable knit that has very little stretch.  If you want to use this stitch for clothing, I suggest that you test it first on a long piece of material for a sample. After you have sewn your sample pull on it in different places along the seam to see how the stitch holds up.

    5) French Seam:  I love this finishing seam.  I use it when I want to create a beautiful, professional seam.  It is used mostly for making a seam look high end. It can be used for lightweight fabric and unlined as well. .  Yes! It does take a longer time to sew this seam than other ways of finishing, but I feel it is soooo worth the time.  Also, it is not difficult, but along with taking more time it does take some amount of patience. There are two types of french seams which will be described below.  My favorite french seam is the first one I discuss below.

         The FIRST way to sew a French seam: This type of seam will show on the outside of the garment or project.  I always use a french seam on a man’s dress shirt: First is to sew the seam together with a ⅝” seam allowance using a straight stitch and with wrong sides together (remember this is opposite of how a seam is normally sewn – which is with right sides together).  The seam allowance will be on the outside. Next, trim only one side of the seam allowance to about ¼”.  Press (always) the seam in the way it was sewn – closed not opened.  Then fold fabric along the seam line with right sides together and then press very well.  When folding fabric along the seam line, I prefer to pin it to keep it in place.  If you choose to use pins make sure to remove each pin as you come to it so as not to run over them and damage either the pin or the iron.  Another good way to ensure the seam is pressed with a nice sharp edge is to spray along the seam line with spray sizing or spray starch (I like spray sizing).  Only time I do not use those sprays is if I’m using certain fabrics, such as silk – a material that will probably stain. With slippery fabrics, such as silk, etc., then it is important to pin the seam so it does not slide around.  This pressing step is important as the next step is performed.

The next and final step is to enclose the seam and sew it down.  Fold the larger seam allowance over the smaller one which will then be enclosed.  Pin as you go along making sure no raw edges are sticking out as the raw edge or fraying will be seen as this seam is on the right side (outside) of item and will be seen.  Lastly, press the seam as sewn on the right side of item.

As you can see, this is a seam finish that takes longer, but it produces a beautiful finish.  After doing this finish a couple times it will not take as long.   

The SECOND method of sewing a French seam:  With wrong sides of fabric together, sew a seam.  If the item calls for a ⅝” seam allowance, sew a ⅜” seam allowance.  Once sewn, trim the seam allowance to ⅛”. Open the seam with right side of fabric facing up.  With right side up, press the seam to one side; then turn fabric to wrong side and press the seam again to make sure it is flat.  Now with right sides together, fold fabric on the seam and press it flat. This is pressed with the seam’s stitching on the outside edge.  Next pin along the pressed edge of the seam. The final step is to enclose the edges of the seam. If your item calls for a ⅝” seam, you were instructed at the beginning of this to sew a ⅜” seam.  So now the material will be sewn with a 2/8” or ¼” (⅜” + 2/8” = ⅝”) seam which will enclose the raw edges. Lastly, turn fabric to wrong side and press the seam to one side; turn to right side of fabric and do a final pressing along the seam.

This type of seam is especially useful for seams that will be seen, such as in an unlined jacket.  I hope you will try this technique. Enjoy!    

 6)  Reverse French Seam:  This is called a reverse french seam because the seam is sewn with right sides together – as most seamstresses are used to.  With right sides of fabric together, sew a normal ⅝” seam allowance. Fold each edge in to the seam line and press. Sew the folded edges together, sewing close to the fold.  This will enclose all of the raw edges.

7)  Clean or Classic Finish:  After the seam has been sewn, turn each side of seam allowance under to the seam line.  Sew each folded edge separately. Press seam open.

8)  Serged Seam:  If you have a serger, it automatically finishes the seam as it is sewn.  But if you do not have a serger, I do not suggest buying one just for that purpose as they are expensive.

9)  Bias Tape:  Another way to finish a seam on an unlined item is to enclose the raw edges with bias tape.  Sew it to each side of raw edge. Bias tape can be purchased at the store or you can make it yourself.