Part of a series that begins with Blocking Notes (Intro).

Yarn Considerations

In general reading the ball band is a good idea, both for general care instructions, and to know what the yarn is made of. If in doubt, test your blocking methods on a swatch to see what the likely effects will be on the finished article. There are some general comments that can be made based on the type of yarn.

Wool and most wool-like fibres can be wet-blocked or steam pressed warm. Angora and mohair are less elastic than other wool-like fibres, while cashmere felts easily, so you need to be careful with these fibres. Some people say that spritz blocking is safest with delicate fibres such as cashmere and alpaca (see [THOM] for example), but since you will want to wash any garment you wear eventually, I see no harm in gentle wet-blocking. Try it out on a swatch first to be safe.

Silk tends to stretch and so after blocking you may want to pull a little on the thoroughly dry swatch before measuring. It is also fragile when wet, so block gently using wet-blocking or spritz-blocking. Cotton, linen, hemp (and other plant-based) yarns tend to stretch with wear so after blocking the gauge swatches you may want to hang a light weight on the dry swatch for a few hours to mimic wearing the article before measuring the final gauge. These yarns can be wet-blocked or steam pressed warm. Linen is strong when wet, so can take a lot of wet-blocking without damage.

Most synthetics don't respond to blocking the way woolen fibres do; they tend to bounce back to the pre-blocked state rather than keep the blocked form. There is a method used for acrylic yarns called “killing” [a href = "http://www.runedesigns.com/2008/12/02/blocking-notes-intro/#DRUC">DRUC] which involves pinning the wet article to shape, then steam pressing through a wet cloth. This is said to make the article keep its shape after blocking, and to drape beautifully. I haven't tried it myself so would recommend testing the procedure on a swatch first.

Stitch Pattern Effects

Wet blocking can be used for any stitch pattern, although care must be taken when pinning the article out to not stretch ribbing or cables too much. If stretched too much, these won't bounce back when dry.

When steam blocking, don't press ribbing, cables, or any embossed patterns, as the pressing will flatten and lessen the three-dimensional effect of the patterning.

Blocking Swatches

I soaked a few swatches at a time in lukewarm water to which a small amount of a gentle hair shampoo had been added for about 20 minutes. I swished the swatches around gently a couple of times. I pressed out the water, and rinsed the swatches using lukewarm water. Then I rolled them in a towel. I pinned the swatches out on a foam board covered with a clean towel. I blew up a balloon inside the hat to block that, measuring to make sure I didn't blow it up too far. Then I let each swatch and the hat dry before unpinning the swatches and deflating the balloon.

I wove in the yarn tails before blocking for the swatches. For the hat, I wove in the yarn tails before blocking and then checked they hadn't puckered after blocking. I sewed on the i-cord loops after blocking.

Part of a series that begins with Blocking Notes (Intro).

Blocking Prior to Seaming

There are conflicting opinions about weaving in tails prior to or after blocking. In theory it's a good idea to weave in the yarn tails that won't be used for seaming prior to blocking, as the blocking process will help them settle in and be less visible, and this is the method recommended in [STAN, p 224]. If, however, you need to stretch the article a lot during blocking, don't weave in the yarn tails as the yarn tails may pucker [HOLL].

For blocking an item prior to seaming, I like to use wet blocking, although any of the methods can work.

Shape the pieces according to the schematic. Every part of the garment that will be seamed needs to be measured carefully to make sure the pieces match. You may need to use a lot of pins to make the edges as flat as possible so that seaming the pieces is easier. It's also possible to steam press the edges of the pieces to make seaming easier, touching the iron to the knitted fabric through a pressing cloth. I've tried this method. I find it tends to flatten the edges so I don't recommend it unless it's a dark yarn that's difficult to seam otherwise. I'd recommend testing on a swatch first, then washing the swatch again to make sure the fibres bounce back from this treatment.

Let the pieces dry completely before unpinning them from the blocking surface.

Blocking After Washing

Blocking after washing is reasonably easy for garments. Press them gently into shape (check the measurements against the schematic of the garment) on a towel or drying rack, and let them dry (you may need to change the towels a couple of times). Some yarns are marked machine dryable and you don't need to block these after washing.

If the article is a lace shawl or tablecloth, then you'll probably have to go through the whole blocking procedure with the pins or dressing wires again. Some yarns do have a “memory” of being blocked and remember the shape somewhat, but whether this is sufficient depends on the pattern, the yarn, and how strongly it was blocked the first time around.

Part of a series that begins with Blocking Notes (Intro).

Blocking always involves water; the three major types of blocking differ in how much water you use and how it is applied to the knitted articles. Which method you choose mostly depends on the type of yarn, although the type of knit, whether you're blocking prior to seaming or after washing a completed garment, and the stitch patterns also have an effect. The ball-band from the yarn should have useful information on it, but the best method is to knit a number of swatches and try out different blocking techniques on them to see which is the best. This is particularly useful if the yarn is unfamiliar, or the finished garment should fit precisely (where stretching or shrinking will be an issue).

Wet blocking is the term generally applied to the process of soaking the knitted articles. Fill a basin with cool or lukewarm water, add a small amount of a detergent, and swish the detergent through the water. The cleansing agent can be a specialized wool wash, or a mild, slightly acidic hair shampoo. A gentle dish detergent such as Dawn also works well, as long as it's detergent and not soap (since soap is alkaline, it encourages fulling). Add the knitted article(s). You can swish the water through very gently to make sure the articles are thoroughly wet, which is why the water should be cool or at most lukewarm. After 15 or 20 minutes soaking time, pour off the water, pressing the excess water out of the articles, and rinse in cool water a couple of times until the water is clear. If the articles are heavy, I find pouring them into a strong colander makes pressing out the excess water gently much easier, without stressing the knitted fabric. Some people put the articles in a laundry bag or pillowcase (one that closes properly) and put them in the spin cycle in the washing machine; this is the sort of thing you want to test out on swatches first. Don't spin dry sensitive yarns such as cashmere that felt easily. If not spin drying, after pouring off the excess water, lay the article flat on a towel, and roll up the towel with the article inside, so that you end up with a rolled-up towel surrounding the knitted item. Leave for a few minutes and then unroll. If the article is still very wet, repeat with a dry towel, until the article feels damp but not wet.

Carry the article to the blocking area, supporting it completely to make sure it doesn't stretch (another use for the colander if the article is large and/or heavy). For blocking garment pieces prior to seaming, block each piece separately. Lay it out on the surface and press gently into shape with your hands. Pin down the edges if they're curling, or if you need to stretch the pieces into the right shape. This is where the schematic and tape measure come in handy; some people use specialized blocking boards with measurements printed on them, or checked gingham to make this part of the process quicker. If you're blocking an entire garment, then usually the pins aren't needed, you just press the garment into shape and leave it to dry (unless you're using a woolly board).

If you're blocking lace shawls or tablecloths, then you probably want to use a bed or the carpet (covered with a cloth) and really stretch out the article, pinning down each peak or picot edge. This opens up the yarn-overs to their full beauty. You can also use dressing wires. To make sure the shape is correct, you should measure the various axes to make sure they match, or draw concentric circles and/or lines on an old sheet and use that to block on. You can also use a specialized blocking board or lace blocking frame.

I like to use wet blocking with wool and yarn mixes that are predominantly wool, as the fibres often need soaking for the full effect. This also mimics the way I'll wash the item later, particularly garments. The yarn will usually soften and relax, and then “bloom” or fluff up a little, particularly if it's woolen-spun rather than worsted-spun. Wet blocking helps even out any inconsistencies in tension and is necessary to make colourwork such as fair isle even and flat. I also find lace blocks best with wet blocking as the work can be stretched better when it's properly wet.

Spray or spritz blocking is the method whereby you pin out the article first, and then spray it with clean water (distilled is best) until thoroughly wet, then leave it to dry. I find it not as effective as wet blocking, but for sensitive articles such as cashmere, or when not very much blocking is needed, it works.

Steam pressing is the method whereby you steam the article, using a hand-held steamer, the steam from a boiling kettle, or a steam iron. If using a steam iron, hold the iron above the pinned-out piece, or press through a pressing cloth (which should also be dampened). Make sure you press, lifting the iron off the article each time you wish to press another area, rather than moving the iron while still in contact. Let the steam dampen each piece thoroughly. Be careful with this method as the heat can damage the fibres, especially synthetic blends.

Part of a series that begins with Blocking Notes (Intro).

The first decision about blocking (after deciding what it is you're blocking, of course) is what you want to block on. If you don't want to stretch the article you're blocking, you can get away with gently easing it into shape using your hands, in which case you can block on any clean surface. Counter-tops, towels, specialized blocking boards, foam mats, foam insulation, homosote boards, corkboard, mattresses, clean carpets, drying racks – anything flat and big enough to hold the article will do. If the surface might absorb the water, or be damaged by it, or it might not be clean enough, then putting a lint-free towel or other cloth on top before laying the knitted article on it is a good idea.

If you want to stretch or shape the article a little more than you can do with your hands, then you need to choose a surface that you can pin the article to. Use rust-free (stainless steel) pins or t-pins; others tend to leave marks on the article that are hard to get out. T-pins are a little stronger and are good for heavier articles or if you need to stretch the article a lot.

If you're blocking garment pieces, it's handy to have a schematic of the size and shape you want the pieces to be, and a tape measure to check the measurements.

Shetland and fair isle sweaters knit in the round are often blocked on a wooly (sometimes spelled woolly) or stretching board (e.g., at Camilla Valley Farm's Wooly Board), which stretches the body and arms of the sweater into the right shape. The only problem with this method is that the ribbing at wrist and hip tends to be stretched too much, so has to be brought back into shape afterwards, which you can do either by steaming the ribbing until it relaxes with a steam iron or over a boiling kettle, or wetting it and patting it into shape. [FEIT, p. 70]

If you're blocking lace or articles with long straight edges using pins, it's hard to get the edges really straight. This is where blocking or dressing wires are useful. These are long, thin, clean stainless steel wires that you thread through the edges of the articles. Then you pin the wires at intervals to the backing surface, which makes the edges straight and can help avoid little triangles showing up as sometimes happens when you just use pins. A variation on this is to use strong thread (e.g., crochet cotton in bedspread size, or buttonhole sewing thread), thread it through the edges, and then tie it to strong pins. When you pull the thread taut, it will straighten the edges.

Those who block a lot of lace often recommend lace blocking frames. The basic principle is to build a frame that looks like a picture frame, and then use a strong cotton thread or string to tie the lace article onto the frame. By adjusting the thread tension and angle, you can adapt the frame to any shape of knitted article, so it's good for shapes that are difficult to block properly using other means. Examples of blocking frames are at Knitpicks and Spannmax.