What is Blocking?
Blocking is a process used to set the garment pieces to their correct size and shape. It is a method of pinning down pieces of knitting before pressing to ensure correct shape and size. It is especially useful with a stockinette stitch fabric where edges tend to roll.
Most garments are greatly improved by blocking the pieces before the garment is made up. Yarn manufacturers often recommend the correct blocking method for their yarns. Some yarn labels advise ‘no blocking’ as certain yarns are unsuitable for this process. Acrylic yarns often come in this category and should be treated with caution.
Blocking works on the idea that damp yarn can be moulded and therefore adjusted to shape and style. The amount of adjustment will depend on the fibre content of the yarn, how it is spun and the stitch pattern used. Natural fibres respond better than synthetics. Blocking is done on a large flat surface, which is usually padded and will take pins. A board of some sort is covered with padding, and finally covered with a cloth.
The diagrams that come with the patterns, give the measurements of each piece of knitting. You will find it easier to pin out the pieces with the purl side facing up. Use plenty of pins and do not pin out your rib to the same measurements as the rest of the garment.
Ask yourself if the garment needs to be blocked. Sometimes you are lucky and your knitting looks fine once it is finished. Do not block unless you have to.
What is Pressing?
This term is very misleading. Pressure from the iron is never required on knitted fabrics as it is on woven materials. Knitting is never pressed or ironed in the conventional use of these words.
If you are going to press your garment, press evenly and lightly, lifting and lowering the iron over the surface. Take out pins and make sure the knitting is dry before lifting it up.
How to block a knitted or crocheted garment
There are several different ways to block knitting. The three main ways to block a garment are:
- cold blocking
- blocking and pressing
- steam blocking
This is the safest method and can be used on most yarns. Read the manufacturers instructions first. In this method moisture only is used to mould the knitted pieces to size and shape.
If you have to block a garment, the easiest method is to soak the garment in water, or to wash it, and then lay it out flat, pat it into the shape and size, and let it dry. You can lay your knitting on a towel or a blocking board. Another option is to stretch the dry garment out to the proper dimensions, and then use a spray bottle to mist it with water, and leave it to dry.
For a garment that really needs to be stretched, wetting or washing, then pinning it into shape with many pins may be necessary. Check the pattern to find the correct size for each knitted piece. You can also use blocking wires which are long stiff (for straight edges) and flexible (for curved edges) wires that are run thorough the edge of the garment pieces before sewing up. The wires hold the edges even and can be pinned down for more stretch in the piece. The instructions that come with the blocking wires recommend pinning out the garment when it’s dry, and then using a steam iron or steamer to spray the garment with steam, rather than wetting the garment. Do not actually iron the fabric, because this may damage it.
For example, if you are blocking a sweater, first block the back, then the front, matching armholes and shoulder and side seams. Next block the sleeves, matching one to the other so that they are the same size. Do not block the ribbed sections.
Lay the section on the blocking board wrong side up, using grid to pin out to correct measurements.
Pin the corners, then edges. The pins should slope outwards. Use rustless, large pins.
When satisfied with size and shape, spray with a fine misted water spray until knitting is damp. Alternatively, you could dampen the knitting first before pinning out
Leave to dry naturally. Do not hurry this stage.
Remove pins carefully.
Blocking and pressing
If you garment needs to be blocked, this is how to block and press.
Place the knitting with the wrong side up on a flat padded surface or blocking board.
Ease piece into shape and then check the measurements. Hold in position with plenty of pins. This is called blocking. As you pin the knitting down check that the stitches and rows run in straight lines and the fabric is not pulled out of shape.
Use a clean pressing cloth which is dry or slightly damp. Press synthetics with a cool iron over a dry cloth and natural fibres with a warm iron over a slightly damp cloth. Leave garter stitch or rib borders free when pressing. Press evenly and lightly with the iron, lifting and lowering the iron over the surface. Take out pins and make sure that knitting is dry before lifting it up.
Here a combination of moisture and heat is used to mould the knitting to size and shape. Read the manufacturer’s instructions first. This method is not usually used for synthetic yarns as they will stretch and loose their elasticity. This method of blocking is best done on a padded board. Do not use to hot an iron.
Pin out garment pieces matching size and shape as for cold blocking.
A steam iron is a good way of applying steam. Hold the iron just above the garment piece allowing steam to penetrate the yarn. Try not to allow the iron to touch the knitting, as this can cause undue stretching of the yarn fibres. Steam can also be applied using a damp cloth laid over the knitting and a dry iron help lightly against the cloth without applying pressure or ironing, that is moving the iron.
Do not unpin pressed sections until they are cold and dry.
How to make a blocking board
This is how to make a blocking board. Cut your board to size, at least 60 cm by 90 cm, or larger. Pad with old sheeting or blankets. Cut a piece of muslin or sheeting 5 cm wider all round than the board. Checked gingham can be used as the squares are useful for measuring. Centre the board over the fabric and stretch and fabric over the edge. Staple or tack at centres of each side. Working out from the centre stretch and staple fabric along each edge. Neatly fold excess fabric at corners and staple or tack. Instead of stapling or tacking the fabric can be hemmed around the edge, and a drawstring added. The drawstring is then pulled tight at the back of the board. Turn to right side and mark off a grid unless you have used square fabric. A useful size for the grid is 2.5 cm squares. If you can be gingham in 2.5 cm squares this is ideal.
Blocking mock rib welts
Slip a ruler into the welt to help pull the stitches evenly together. A new wooden ruler is suitable for children’s garments, but something longer will be required for adult. Inset the ruler of bar into the welt and gently but firmly pull the stitches of the welt together holding the bar with one hand and the knitting with the other.
Lay the welt with wrong side uppermost on the ironing board and place a set cloth over it. If you have a blocking board use this instead of the ironing board. Hold a hot iron over the wet cloth for a few moments to allow the steam to penetrate the welt. Use very little pressure. Remove the cloth and gently pull the stitches once more and pull out the bar without disturbing the stitches. Leave the knitting untouched until it is completely dry.
Before blocking it is important to check whether the yarn is a natural or a man-made fibre. Have you read the ball band for any special notes on finishing? There are different types of yarn. Yarns made from natural fibres such as wool, angora, mohair, silk or cotton can be blocked using a damp cloth to help smooth the fibres or the yarn and improve their appearance.
Mohair and angora may not require blocking if the surface of the stitch is patterned. Blocking is only required where it will smooth uneven fibres.
Blends on wool and nylon, provided the amount of wool is greater than the amount of nylon, can be treated in the same way as wool. Blends of wool and made-made fibres such as polyamides and polyesters should be pressed under a dry cloth with a cool iron. Courtelle, Orlon, acrylic yarns and glitter yarns should not be pressed unless you are advised that it is safe to do so on the ball band.
Smooth textures or simple patterns based on stocking stitch require blocking. The process evens out the surface of the yarn giving the fabric a better finishe. Raised, ribbed or chunky patterns usually need no blocking and may ewven be spoilt by losing their surface interest.
Garter stitch or patterns based on this stitch should not be blocked because they are included to lose their fluffy light texture and appear to become more dense and flattened.
Special attention is required for ribbing. Pulling ribbing edges apart with the fingers and then pin. Opening out the ribs helps to get a smooth fabric above free of creases. Ribbing itself should not be pressed If you accidentally press ribbing, garter stitch or any other stitch that should not be flattened it may be possible to steam back into shape provided the yarn i wool or a wool blend more than 50% wool.
Place a hot iron against a wet cloth with no pressure at all on the knitting. Alternatively, lay the knitting on a drying rack or on a wire tray resting between two supports. Hold a boiling kettle below the knitting. Do not hold the knitting whilst you steam because it is all to easy to scald yourself. It is possible to purchase a steaming kit which will make steaming knitted garments easier. It is also possible to use a steam generator iron.