A Primer on Sewing Knits - Threads


Get Threads magazine!

Subscribe Renew Give a Gift

A Primer on Sewing Knits

Knits give you great leeway when fitting and are very comfortable to wear.
Knits give you great leeway when fitting and are very comfortable to wear.

Knits give you great leeway when fitting and are very comfortable to wear.

by Ann Person
from Threads #73, pp. 42-45

Let me quickly dispel the apparent mystery about sewing with knits: there isn't any! Nonetheless, after 30 years of writing and teaching on the subject, I'm always surprised to find out that these supple fabrics still alarm many sewers. And nowadays there are so many new knit fabrics available, it's hard to know how to handle them all. So I'd like to present a basic primer of information every sewer needs to create knit garments that look like ready-to-wear. And believe me, it's easy- you don't have to be an expert.

The great fun of sewing with knits is the leeway they give you when fitting. A garment made from a stretchy fabric doesn't have to fit as perfectly as one made from a woven, so knits eliminate the pressure of exact measuring and altering of patterns. And they're so comfortable to wear!

When constructing knit garments, the first rule is that if the fabric stretches, the seams must stretch, too, so that the stitching won't pop as you bend and move in the garment. Whatever type of machine you have, I'll show you how you can achieve flat, stretchy seams.

Knit fabric sampler
Select patterns designed for knits when you sew these forgiving fabrics, available in an amazing variety of weaves, prints, and blends (including printed cotton interlock (1), silky rayon/metallic (2), mohair/wool jersey (3), striped acetate rib (4), and lacy linen/nylon jersey (5)).


Check out the fabrics!

Whether made of cotton, wool, linen, one of the new synthetics, or a blend, each knit falls into one of several construction categories: single knits (created on a commercial knitting machine with a single bed of needles); double knits (created on a double-bed machine with two back-to-back beds of needles); and rib knits (made by alternating stitches between two needle beds). Single-knit fabrics like jersey, velour, terry, and fleece look different on the reverse side, have cut edges that curl, and usually have about 25-percent stretch. Double knits like interlock (made with fine yarns) tend to be more stable than single knits, often look the same on both sides, have cut edges that don't curl, and stretch from 25 to 75 percent, depending on the fiber and construction. Rib knits, constructed from alternating knit and purl stitches in various combinations, may look the same or different on opposite sides, tend not to curl, and have up to 100-percent stretch.

My philosophy for fabric preparation is to always pretreat a fabric before you sew it exactly as you plan to care for the finished garment. This means that cotton, linen, and synthetic knits should be washed and dried (in the dryer if you plan to dry them this way later), and wool knits should be thoroughly steamed before cutting.

Smart pattern choices
When planning a knit garment, I recommend selecting a pattern specifically designed for knits, rather than for woven fabrics, because the pattern will have the correct amount of ease built into it. The amount of stretch in the fabric will determine the style and size pattern you choose. Check the pattern envelope for suggested fabrics and the amount of stretch required for the style. If you choose a fabric with less stretch, you'll need to add more ease.

Since knit fabric has built-in ease, you don't need as much ease in the pattern as you would for a woven fabric. A couple of inches of bust ease, for example, is plenty for a fairly fitted knit style, compared with the 5 in. of bust ease needed for many woven garments. And a double-knit skirt hangs nicely with 2 in. of ease, while a woven skirt would require at least 3 to 4 in.

1 | 2 | 3 > View all
ThreadsMagazine

Comments (11)

user-1109384 user-1109384 writes: I have some 54" wide, fine wool that I would like to make two scarves with, i.e., cut lengthwise. While I plan to create a fringe along the crosswise grain, how should I finish the long, cut edges? Would a tiny, rolled hem work?
Posted: 11:56 am on November 8th

Stacywacy Stacywacy writes: I've had a lot of success sewing knit fabric seams by putting tissue paper under and on top of the fabric as I'm seaming it. Doing this allows me to use a regular sewing machine instead of my serger and it definitely minimizes any tendency to ripple.
I STILL haven't figured out how to successfully sew clear elastic to stabilize a seam though. If anyone has specific instructions for that, I would love to read them!!
Posted: 1:14 pm on August 24th

CBarnesGallagher CBarnesGallagher writes: Ball-point needles successfully have created my seams on jerseys and velours. I found that sharpies may cause problems as I've always tested a sample before proceeding with actual construction. Instructions on needle packages and in machine manuals are specific and reliable about this. Only on woven cloth do I rely on sharpies! The sample fabric is also important to wash-dry testing, as we know. Also, referring to the owner's manual is important to the maintenance of upper- and lower-thread tension. My machine does overcast without fail, and my Brother was much more affordable than others, and I've been maintaining it for about 30 years. I do clean, lube, and adjust it as necessary. I always create the first seam, then turn the garment or linen/curtain around to overcast it. Then, I stitch again .25" away from the seam line to create an easy but reliable French seam, even on all velours and jerseys. For some applications, I do continue to recommend Herringbone stitches, etc. by hand although the process is so consuming that I rely on machine whenever possible. Velours and jerseys are so comfortable.
Posted: 3:17 pm on February 4th

Susiesmom Susiesmom writes: Don't forget one of the premier sources for quality knit fabrics in the country: Christine Jonson (cjpatterns.com). She's a respected designer and author, who's appeared in Threads and many international publications. Her patterns are stellar and her knowledge of knits formidable. She's our favorite source for fabric and patterns here in Michigan.
Posted: 7:55 pm on June 18th

SanMarGnd SanMarGnd writes: To keep your seam from bunching up as you start to sew, do not back stitch. Instead put the feed dog down and sew a couple of stitches in place, then put the feed dog back up and continue to sew the seam. No bunching, you can end the seam the same way.
Posted: 1:26 pm on January 26th

SanMarGnd SanMarGnd writes: Usually what the garment industry uses is the clear elastic. However, whenever I sew the shoulder of a knit garment I simply cut a strip of the same fabric on the lengthwise grain and apply it to the shoulder at the same time as I sew the seam together. I use the serger so the fabric is trimmed at the same time as the shoulder seam. This stabilizes the seam just fine. and is not too bulky.
Posted: 1:21 pm on January 26th

NotMySister NotMySister writes: What do you do to correct the material from bunching up when you start and do a back stitch? I just returned to sewing after years from it and I still haven't figured that out.
Posted: 11:18 am on July 28th

SawaSawa SawaSawa writes: Hi Dembie,
Not sure if this is what you are looking for but I think it is called plastic elastic. It is inexpensive, commonly used in knit garments at shoulder seams to stabilize them. I've seen it at 'Beverly's' and it's probably at other fabric stores... below is a link to it at Beverly's. Below that is a link describing how to sew it into knits.All the best.

http://www.beverlys.com/catalogsearch/result/?q=clear+elastic

http://sewing.patternreview.com/cgi-bin/review/readreview.pl?readreview=1&ID=486


Posted: 9:02 pm on August 31st

AprilO AprilO writes: Thanks for this, I think I might finally overcome my fear of sewing knits. I especially like your trick of using a straight stitch and pulling the fabric, my old Brother Pacesetter has a built-in stretch stitch but it is extremely slow and tedious.

Also --- help! I just bought a kimono dress pattern not realizing that it is for stretch knits only. Can I just add extra ease to the pattern to make it out of woven fabric? If so, how much should I add?



Posted: 5:28 pm on July 13th

miedrn miedrn writes: I believe the "stabilizer" you're talking about can be interchanged with clear elastic that you can use on shoulder seam lines. It's what I use - try it. You can get it at JoAnne Fabrics.

If this isn't suitable, I'm sure someone else will chime in!
Posted: 9:47 am on April 10th

Dembie Dembie writes: I need to alter some knit tops. I am noticing that the shoulder seams have a transparent plastic strip sewn in with the seam. It is not fusible but works excellent as a stablizer to keep the seams from stretching too much.But it can stretch a little.

There are no places to buy sewing supplies here. They went out of business years ago. I can't find an internet supplier of a roll of these strips.

Can buy plenty of patterns and knit material online; but no one mentions these plactic strips even though ready-to-wear seems to have them is almost all their sewn knit tops.

Would love some info. Tks.

Posted: 5:16 pm on March 21st

You must be logged in to post comments. Log in.