How to Move Darts and Change Necklines : Slashing & Spreading (Pattern Drafting)

Alright, after the last few posts you now have got a basic 2 dart bodice block pattern (you do right?). So what can we do with that? We can use the bodice block as is, with one dart at the waist and one to the side, it works great and I myself use this basic bodice style for nearly all of my dresses. Often I use this 2 dart bodice pattern but modified to have a kimono style sleeve instead of a set in one, which is a modification I explain here. The different fabrics, necklines, sleeve styles, and other details can make this same very standard 2 dart bodice pattern look very different or work for a verity of eras.

For my white eyelet dress I used my basic 2 dart bodice pattern. The only change in the pattern for the dress above from my basic bodice block was to draw on a v-neckline, super simple!

Still, you don't have to stick with one waist dart and one side dart, you can move one or both of these darts to create some different style lines! Or perhaps instead of a dart you want to use gathers instead? Darts are used to make the fabric curve to the shape of the body, taking in fullness to create shape, but of course this fullness does not have to be controlled with a dart. You can use pleats, gathers, smocking, or darts to reign in fullness and using the slash and spread method of moving around fullness means you can move the area where fullness is controlled around too. For example the dress below is again a variation I created from my standard 2 dart bodice pattern, first I used the slash and spread method to move the side dart to the neckline and then instead of actually sewing the dart I instead used gathers to control the fullness.

The red lines here show where the darts are on the pattern, but while I sewed the waist dart as usual, I gathered the fullness of the dart at the neckline instead of actually sewing the dart.

Most if not all bodice styles are created by manipulating the excess fullness created by fitting the fabric to the body with darts or style lines. You can transform the standard darts of a pattern into a style line or princess line quite easily, but I'll be showing you that another day. Today lets simply look at how to slash and spread to move darts around.

Endless possibilities!

So the darts, and in turn fullness, radiates from the apex (bust point) on women's patterns. All darts usually point to the apex, and gathers usually radiate back to the apex as well. Different style lines or additional added fullness can go against this basic principal, but when starting with the 2 dart basic bodice block pattern, you are usually going to be moving darts around the apex.

Lets start by tracing a copy of the front basic bodice block.

Above we see our two darts drawn in blue.

If we wanted to move one of these darts to say the mid arm area (in red line above) we draw a line from the apex to the mid arm. If we would like to move one of the darts to the neckline (green line above) we would draw a line from the apex to where we'd like the dart in the neckline. Easy, just draw a line from the apex to wherever you want to move the dart.

Now go to the dart you want to move. In this example I am going to be moving (or closing rather) the side dart and moving that dart/fullness into the neckline (the green line). Draw a line from one of the dart legs to the apex. Cut along this line right up to the apex point but not through it.

Also cut along the line where you are moving the dart/fullness to. Again you want to cut all the way to the apex point but not through it, leaving you a tiny smidgen of paper intact at the apex to use as a hinge of sorts.

See, the two cuts allow you to hinge the bodice from the apex, now you can overlap the paper at the side dart to close it. You have slashed (cut the paper) and now you can spread (the new dart open).

Above the bodice is hinged with the dart legs of the side dart overlapped so that dart is closed. This opens up a dart shaped wedge of space in the line you drew/cut from the neckline. Tape the side dart closed like this.

Next fill in that new neckline dart with some spare paper and tape.

Then of course, because I was doing this to demonstrate, I forgot to demonstrate a vital step! Mark the end of the dart up 1/2"-1" up from the apex inside the new dart. Then draw your actual dart legs out from this point as seen in red above. The closer your dart point is to your apex, the pointier your bodice will end up. So if you want your bodice to fit sorta-pointy over a bullet bra for example, having the dart point close to teh apex is useful, if you want the bust point of the bodice to be quite smooth, put the dart point farther away from the apex, just not too far, around 1" perhaps. As always, when you are new to pattern drafting and manipulation, I suggest you make a mock up/muslin version of the new pattern before you dive into using your new pattern for a dress!

Anyways...Cut off the excess paper.

What about the paper sticking out from the edge? Well fold your paper jsut like you will be sewing your dart, most of the time the dart fullness is ironed towards the center front but eh, rules are made to be broken...if you want, so here I have the fullness folded out but really it should be folded towards the center front. Most of the time when I move darts to the neckline it is so I can gather the fullness instead of use it as an actual dart so this won't really matter in that case and I just round out the neckline.

Snip off excess.

If you unfold the above it looks like this, which may look silly but it would lay nicer like this than it would if you just cut this straight across and sewed the dart, I'll show you why.

If you did just slice that bit off it looks like this.

Then when you sewed the dart, the excess that you would iron towards the arm hole (in this hypothetical case) would be loose on the inside of the dress and could create wrinkles or be seen through on the outside. In the image above, due to the transparency of the paper, you can just see how this dart would be free to move around and not stay laying flat on the inside of the garment.

Another option is to redraw the curve of the neckline if you intend to use gathers here now instead of a dart. This is how I created the pattern for the floral dress in the photo near the beginning of this post.

Somehow I feel like that came out more confusing than I had hoped! It is funny how something that seems so simple to me (after years of practice) is so difficult to explain clearly! As always, feel free to ask for clarification in the comments.

So what about just changing the neckline? That's super easy! You can do this to basically any pattern you have, be it self drafted or a commercial pattern!

In the image above you can see that I am using the same pattern but that I have undone the moving of the dart and taped it back together as it was at the start. So now it is just the traced basic 2 dart bodice block again and we can draw on any shape of neckline! Our basic bodice block (and sloper) have a high rounded neckline so that eventually we can use the high neck of the pattern to make collars, but you can draw on any shape of neckline that you would like.

You can see I drew a squared line (in blue) out from the apex to the center front as a guide to know how low cut the necklines would be. Knowing that the apex of the pattern corresponds with the point of the bust on ones body means we can use our understanding of the apex point as a reference when drawing necklines.  I tend to like higher more "modest" (whatever that means) necklines, so I stay at least about 2"-3" above this apex line reference point.

So go ahead, draw in a V-neckline (the blue line above), a wide boat-neck style neckline (the purple line), a rounded neckline (in red) or a low square neckline (in pink). These necklines can be finished when sewing the dress up in a variety of ways, by lining the bodice, with some sort of binding (like bias), or by making facings. I'll be covering how to make patterns for facings next time!

Just remember, whatever change you make to the neckline/shoulder area on the front you must mirror and change on the back as well! Also remember for the necklines that where you cut the paper will be the cut edge, not the sewing line. Essentially remember to add seam allowance on or keep seam allowance in mind when drawing the necklines.

Both of these modifications are actually some of the very easiest to do, though somehow I think that gets a bit lost as I try to explain them! Just like I am constantly trying to improve my pattern drafting skills, I am also trying to get better at explaining this sort of thing and at writing tutorials. Please do ask for clarifications or point out areas where I have explained things poorly! I want to improve!

Also, if you want me to explain how to draft a particular style of bodice, please do submit requests for future tutorials! Comment below with links to images of dresses or old patterns you would like to know how to make self-drafted patterns for and I'll do my best to explain/show how to modify the 2 dart bodice block to make that style. I'll go over some styles in the future, but it would be cool to do ones I know you all are interested in seeing.

Have a good weekend everyone, happy sewing!