Friday, 10 April 2015

Tension, Blocking & Pressing

I am aware that there has been a lot (and I mean A LOT) of discussion on social media about the tension (that is the number of stitches and rows to 10cm) being achieved when working through the first set of patterns for the Lily Pond CAL, so I am writing this blog post to try and help those of you who are struggling to achieve the correct tension and explain why it is important.

If you are happy with your tension and are looking on the blog to find the tips and techniques for block one, skip this post and go to ‘Lily Pond CAL – Stripes and Waves’ which you will find lower down.

If you are struggling with your crochet tension in relation to the Lily Pond CAL and have a spare 15 minutes, make a cuppa, grab a biscuit and read through ALL the following information. If you still have questions having read through this blog post please contact Stylecraft via Facebook or email.

Explanation of yarn weight in relation to tension:
Most yarns on the market fall into set categories according to their weight. In the UK we have the following standard weights: 1, 2, 3 & 4ply, DK (double knitting), Aran and Chunky. The yarns used within the Lily Pond design (Life DK or Special DK if you have substituted) are standard DK weights.

Yarns within each weight category should conform to the same standards, one of which is the suggested knitted or crocheted tension. Most ball bands will show you the suggested tension – on Stylecraft yarns this tension is for knitting and in is the standard tension for DK, which is 22sts and 30 rows to measured over 10cm.

Yarns sit within the categories to make it easier to ensure that things come up the right size, this is especially handy when substituting yarn, as, in theory, a DK weight yarn should achieve the same tension regardless of brand or yarn content.

The ball band on the yarn will give you the suggested tension and also a needle or hook size that this tension is to be achieved on. For a standard weight DK this is usually a 4mm knitting needle or crochet hook.

Why you should achieve the correct tension:
If you are crocheting to a tension other than that suggested in the pattern there is no guarantee that your pieces will fit together properly, that you will have enough yarn within your kit to complete your project or that your completed blanket will come out the right size.

The look of the crochet stitches can also differ – a looser tension is not as neat as the standard tension, whilst a tight tension can make your work stiff or cardboard like. A looser tension will use more yarn, a tighter tension will use less.

How to achieve the correct tension:
Many knitters and crocheters simply assume that they will achieve the correct tension. This is a totally logical conclusion to make; after all, the information on the ball band or within the pattern is based on what the ‘standard’ tension is. In practice, however, many knitters and crocheters do not attain the correct tension naturally and therefore do not achieve a tension that sits within the ‘standard’.

Before the first set of CAL patterns was released I wrote a blog post about what preparation you could do in advance of starting the project. A copy of my post was (and still is) available as a PDF document on the Stylecraft web site.

One of the key parts of this post was working a tension piece. So that you don’t have to refer back to a previous blog post I have copied and pasted part of the blog below so that you can see what I wrote about tension:

If you already have your yarn and the correct hooks then you are ready to work your tension pieces.

Taking the time to work these blocks can seem like a waste of time, but it is REALLY important that you are sure you are working to the same tension as the tension the patterns are written for. A failure to work to the correct tension will mean that your project will come out a different size and that you will use a different amount of yarn.

If you are using Life DK or Special DK and have full 100g balls you will have enough yarn in almost all of the shades to work your tension pieces and still have enough to complete your CAL project. When I completed the project I had at least a 3rd of a ball of all shades except the Fern and Teal left over – I only had approx. 20g of these 2 shades left so I would suggest you don’t use these for your tension pieces.

When working a tension piece it is a good idea to work on more stitches and rows that the suggested tension. I used 28 or 29sts and worked at least 4 more rows of the stitches so that I could measure a true tension within my pieces. See my images for a guide.

Double Crochet – dc (US single crochet – sc)

Using 4mm hook
Tension = 20 sts and 22 rows

Treble Crochet – tr (US double crochet – dc)

Using 3.5mm hook
Tension 20sts and 10 rows

Please note the hook sizes above – a smaller hook is used to achieve the treble crochet (US double crochet) tension

The tension is taken from unblocked swatches – I stuck mine down to the work surface with double sided tape (being careful not to stretch them) so that they were less curly and easy to measure.

Pre Blocked and Blocked Tension:
If you are used to making projects that feature a repeated motif (such as a Granny Square blanket) or repeated stitch combination (such as a chevron or zig zag) you have probably never worried too much about your tension and, even if you have achieved the incorrect tension, it has probably never really mattered, however, in the case of the Lily Pond blanket (because not all pieces are the same size) you need to be sure that your pieces will fit together.

When designing the project I worked on a grid pattern that was divisible by 15cm and I designed to 3 set sizes as follows:

Square pieces: 15 x 15cm
Smaller rectangles (of which there will be 8) 15cm x 30cm
Larger rectangles (Block one) 15cm x 45cm

Because the crochet pieces will stretch a little when you block and press there is (in most cases) a lee way of approximately 0.5cm between pre blocked size and blocked size.

The measurements given in the pattern for Block One is the pre blocked size. Measuring to a pre blocked size rather than a blocked size is more accurate as crocheters could over stretch their work to achieve the blocked tension. It is my understanding that Stylecraft will add blocked measurements into all the forthcoming patterns

Factors that can affect your tension:
Many things can make a difference to the tension you achieve; I have listed 5 of the most common below:

Your level of expertise:
If you are a newcomer to the craft of crochet you may well find that your crochet tension will change as your ability improves. When launching into a project like this it is worth making sure you have put in enough ground work to ensure that you are working in the right way and that you have the ability to work consistently. 

Your mood or situation:
If you are a bit stressed or have had a bit of a tough day you may find that this will have an effect on your crochet tension. Equally, having a few glasses of wine or watching a funny or enthralling movie whilst crocheting can also cause your tension to change.
As a general rule try to crochet in the same kind of situation whenever possible to ensure that everything stays as it should.

Hook Sizes:
Make sure you are using the correct size hook.
For the most part of the project you will be asked to use a 4mm hook. Please check that you have not mistakenly used a UK 4 (imperial size) or a US 4 or 4/E
I have pasted a chart below to help you double check:

Number of stitches:
It is quite common to achieve the correct tension on a swatch only to find that it is not correct over a larger piece. This is because tension can change as we relax into the rhythm of a repetitive crochet action.

Make sure that you measure your tension over the pattern once you have crocheted at least 8cm just to be sure you are continuing to work with the correct tension

Measuring too soon:
It is really important that you measure your tension to at least 10cm – if in doubt measure over a larger piece, say 15cm or even 20cm just to be sure. Putting the ground work in at this stage can save you a lot of unpicking later on.

If you have achieved a different tension to the tension in the pattern:
If you have done your tension pieces and achieved more stitches and rows to 10cm this means you are working too tight. Rather than trying to change your crochet method (by consciously crocheting looser) simply change up to a size larger hook. If you are still too tight then try another size larger. Make a note of how many sizes you have had to change by so that you are sure to make the swap for each of the 3 sizes.

If you have done your tension pieces and achieved fewer stitches and rows to 10cm this means you are working too loose. Rather than trying to change your crochet method (by consciously crocheting tighter) simply change down to a size smaller hook. If you are still too loose then try another size smaller.  As above, make a note of how many sizes you have had to change by so that you are sure to make the swap for each of the 3 sizes.

Make sure you work tension swatches over double crochet (US single) and treble crochet (US double) noting the change in hook size between the 2 – double crochet tension piece should be worked on a 4mm hook and treble crochet tension pieces should be worked on a 3.5mm.

What you can do if you cannot achieve the correct tension:

If your tension is correct to stitches, but not rows or visa versa:
If you have the correct number of stitches to 10cm your piece will come out the correct width, but if you have the wrong number of rows it will come out the incorrect length or visa versa.

You may find that you can block your piece to the correct size, however you might need to add in stitches or rows to make sure things come up completely right. Adding in or subtracting rows or stitches can mean your making process becomes really complicated, so it may be worth reading through the following information on the ‘rule of thirds’ before you make any changes:

Working Block One to the rule of thirds:
As you can see from the info above, under the heading 'Pre Blocked and Blocked Tension', I have worked to a rule of thirds when designing Block One. The block will be the equivalent size of 3 square blocks – you can see this more clearly if you look at the schematic drawing at the end of the pattern.

If you have achieved a different tension to that suggested, you could choose to work to the rule of thirds rather than spend ages working to achieve the correct tension. I have used the 2 examples below to explain this:
  • Example:
  • Block One piece measures 12cm x 26cm – Square motif will need to measure 12cm x 12cm to fit. 
  • Block One measures 16cm x 48cm – Square motif will need to measure 16cm x 16cm to fit
You wont be able to test this out until the next set of patterns (which includes a square motif) is released on the 21st April.

I really hope this post has gone some way to help those of you with questions about tension. It is common at the beginning of a project for crocheters to over worry about this, but at the same time it is important to ensure that you are working in the correct way. If you are in any doubt at all about your tension it may be worth holding fire until the next set of patterns is released as you will be able to measure your pieces against each other to see if they match – in theory your pieces should fit together even if your tension differs to mine, so long as you work consistently and the rule of thirds applies.
It has taken me quite a while to write this post in an attempt to cover as many queries as possible so I apologise if you have been waiting patiently on this sunny Friday afternoon!

I hope you have a great weekend!

Jane x x