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This is an odd looking measurement. We are going to measure from the point C towards the point B, a distance of one half the CHEST measurement plus one half the DART size, and mark the resulting point (point T). These two measurements require some explanation. The DART size is not actually a measurement, but it is scaled with the bust size and hence is treated in a way similar to the measurement estimates already presented. The CHEST measurement is the width of the chest at the front of the body, above the bust but under the arms. However, the CHEST may also be computed from the BUST measurement. Nonetheless, the CHEST measurement may vary quite a lot from the estimate - it is advisable to measure this separately.

Here are the calculations for the CHEST measurement if an estimate is used : add or subtract 1.2 cm to 32.4 cm for each 4 cm bust increment above or below 88 cm if you are using metric measurements ; add or subtract 1/4" to 12-1/4" for each 2" bust increment above or below 34" in Imperial units. Also, here are the DART calculations, which you will need as this cannot be measured directly : add or subtract 0.6 cm to 7 cm for each 4 cm bust increment above or below 88 cm in the metric system; add or subtract 1/4" to 2-1/2" for each 2" bust increment above or below 34" in the Imperial system. Make a note of the DART width as calculated here. Draw a vertical line up from point T to just below the level of the line HI.

13 Comments Sign in to add a post

  • Missing

    Nov 19, 2016, 01.54 AMby Maria Robert

    Hi there everyone! I seem to be having problems with step 20 every time I draft it I end up with a tiny armhole does anyone have any suggestions? I’m at a loss :(

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    Feb 27, 2014, 06.22 PMby Pythonesque

    I’m reading this theoretically at the moment and haven’t yet taken my measurements. However, I’m wondering whether the dart size adjustments work right for someone with a large bust measurement but relatively small cup size – at the moment I’m overweight so probably a B cup, but used to measure in theory a 37 AA … I’m imagining that the process used here could conceivably produce more generous bust shaping than necessary for someone who is big all round (I’m about 6’ tall but in average proportion rather than “normal” body and long legged as some are)

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    Oct 19, 2012, 10.45 PMby littleone1

    hey everyone, i got really confused with this step aswell.

    For the chest measurement: When it says chest it means your front chest measurement so you need to measure the front of your chest, above the bust, from your left armpit to your right armpit.

    For the Dart measurement: you start of with a base dart measurement of 7cm if your bust measurement is bigger the 88cm then you need to add 0.6cm to the base dart measurement for every 4cm the bust is over 88cm If it is smaller then 88cm then you need to subract 0.6 from the base dart measurement for every 4cm your bust is under 88cm.

    hope that clears things up for people :)

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    Oct 14, 2012, 09.49 PMby Ellendra Nauriel

    I had the same problem that many other commenters had, and I think the key is in the next step, where it says the line CU should be half the bust seperation. Well, I must have a very narrow bust seperation, because they were nowhere close. So, If CU is 1/2 seperation, and TU is half of CT, then CT must equal the bust seperation. That’s a lot easier to measure, and will account for some of us who aren’t of standard proportion :)

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    May 30, 2012, 04.21 PMby Sarah Clark

    In step 20, the measurement I get goes all the way past point p. Should i quarter the chest instead?

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    Oct 11, 2011, 12.22 AMby AvaGardener

    This might be helpful for figuring out the dart size:

    Dart Size = 7.0 + 0.6[(Bust-88)/4]

    If the bust measurement is more than 88 cm, you’ll be adding to the base size of 7 cm, and if it’s less than 88 cm, you’ll be subtracting (because the second part of the equation will end up being negative).

    I had a hard time sorting out the formula from the text, but eventually figured it out from the other comments. Hopefully this helps!

    2 Replies
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      May 3, 2013, 09.36 PMby fabrichild

      i have always wondered how to convert this formula to inches. I work better using imperial units, but whenever i make my patterns, i have to convert the measurements to centimeters so as to compute for this formula.

      i’ve tried converting the variables, but the results are not the same.

    • Missing

      May 7, 2013, 02.44 AMby Gemise Reddic

      Thank you so much! It was starting to read like a math word problem and my brain wants to shut down.

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    Jul 10, 2011, 05.03 AMby Andie Giddings

    No matter if I use my own chest measurement, or the calculated measurement (which is a little smaller) I am left with very little room (less than 5 cm) between both sides of the blocks…not enough room to create rounded armscyes – it’s very narrow and tilted, coming to a sharp point at the bottom. I’ve gone over and over the measurements about 5 times and I cannot, for the life of me, figure out what I’ve done wrong! Help?

    1 Reply
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    Jun 2, 2011, 05.38 PMby celticstitcher

    This is great but am I right in thinking that the by using CHEST/2 at instruction 20 you are assuming that the back and front are the same width at that point? I am large busted – GG cup and seem to have a smaller back. when I measure my chest it is 42" and if I measure from side seam to side seam accross my back it is only 19". would it be a better fit for us large ladies if we used actual meaurements instead of CHEST/2?

    I’m going to give it a try when I finish my current project, I’ll try both ways and see what works :-)

    1 Reply
    • Photoge01_large

      Jun 3, 2011, 01.55 AMby gedwoods

      If you look at the instructions carefully, you’ll see that no such assumption is made. The CHEST measurement does not include the BACK measurement, which is measured separately. In general, the use of the default equations to estimate these values is inferior to using a direct measurement. The further you are from the “norm”, the better the result will be of using a direct measurement instead of the formulaic estimate.

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    Oct 2, 2010, 06.48 PMby neruda88

    How would I decide my dart measurement? My bust is 87.6 cm which isn’t an increment of 4 below 88.

    1 Reply
    • Photoge01_large

      Jun 3, 2011, 02.00 AMby gedwoods

      For a bust size of 87.6 cm, it is so close the to standard size of 88 cm, you just use the nominal 7 cm DART size. If you really want to take into account the different, you subtract 0.1 cm from 7 cm (i.e. the dart size is 6.9 cm), but as you can see this difference is very small.

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    Jul 30, 2010, 04.33 PMby juliahollmann

    Hi, so far I was able to follow your descriptions. But I seem to have made a mistake, since the distance TC that I calculated is longer than the distance LC.

    My bust measurement is 92 cm … Half the bust plus 5cm = 51 cm length of the paper I calculated my chest following your formula = 33,6 cm + half the dart size (7,6cm/2) = 37,4 cm for the distance TC If I draw that distance from Point C towards point B, the resulting point T lies to the left of point L.

    Where did I go wrong? Thanks for your help

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    Mar 24, 2010, 10.02 PMby reneebies

    how far under the arms do you measure the chest (and back for that matter)?

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    Mar 14, 2010, 10.02 PMby Peacock Strings

    i also need help with this step my back measurement is 15" but i dont know how much to add or substract for the dart………………PLEASE HELP

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    Feb 26, 2010, 05.18 PMby cat42

    I’ve read and re-read your explanation of dart size, but cannot figure it out. Although I’m American, I am comfortable with metric measurements, which I use when drafting the sloper. In the instruction for DART size, you say to add/subtract a certain amount for each bust increment, but I don’t see what to add/subtract it FROM. And also that certain amount is a huge range, from 0.6 to 7 cm (for each bust increment). How do I know where I that range I am?

    2 Replies
    • Photoge01_large

      Mar 21, 2010, 08.35 PMby gedwoods

      Sorry if my instructions aren’t clear enough. If your bust measurement is, say 96 cm, then it is 8 cm larger than the reference bust size of 88 cm. The instructions say that for each 4 cm you need to add 0,6 cm to the base DART size of 7cm. So in this case, you would add 1,2 cm to 7 cm, to get 8,2 cm as your final DART size.

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      Apr 5, 2012, 06.53 PMby steph1230

      Same here! Just thought I’d echo this point. I’ve been unable to follow this step, the wording is not clear; an example would have been helpful.

    • This is a question
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