This is really meant as support material for my Flat Pattern I students, to help them with their sample problems. The rest of the world might find this completely boring. ;)
Students in my class: This covers how I want you to handle simple single dart manipulations, and the format I would like to see your samples worked up in.
Students in anyone else’s classes: However your teacher says to do this is The Right Way(tm) for their class. Seriously.
Teachers of other classes, especially if you use the Armstrong book: You have free use any of this if it’s at all helpful.
People wondering why I’m doing this here: It’s the format I’m used to writing demos in. That makes it easier, and increases the chances of it getting done. Also, this is maybe, just possibly, useful to someone working with doll blocks… ;)
Ok, let’s go!
For the first two sets of simple, single dart manipulations, the first thing you will need is a copy of the single dart front sloper. There should be a pile of them in the classroom, but you can also scan/print or copy page 787 in your text book. You will also need the handout for the sample set you are working on.
Look at the sample sheet and find the new dart position (red line on small figure here). On the sloper, draw a line in a similar position.
Cut out the sloper, including the center of the dart.
On the new dart line you just drew, cut to (but not through) the bust point. Go right to the very edge of the black dot.
From the top of the existing dart, cut to (but not through) the dart point.
At this point, you should be able to swing the piece of paper between the old dart and the new dart freely.
Mount your sloper on a sheet of colored paper with the new dart open and the old dart closed, but not overlapped, at the very bottom. The top of the dart will have some overlap. That is ok. Quick Tip: before you tape or glue your sloper down, use a ruler to check to make sure you’ve left room for your seam allowances!
I use Rubber Cement to attach the sloper to the colored paper. The bottles are usually shaped about like this. Find the cheapest one that says “Rubber Cement” on the bottle.
Measure the new dart opening. You need to mark the middle of the opening. This dart opening is 2 1/2″, so my mark will be at 1 1/4″.
Draw a line that connects the bust point and the middle-of-dart mark you just made. If your math was right, this is the center of your new dart.
We can’t leave the dart point right on top of the bust point. We need to move the dart point out along the line we just drew in the middle of the dart. Make a mark 1/4″ away from the bust point on the line you just drew.
Please note: this is a 1/2 scale sloper. We are using this 1/4″ measurement because that is what was used with the original dart.
Fold the dart shut. Remember, vertical darts fold towards the center line of the body (Center Front in front, Center Back in back), and horizontal darts for down (because gravity). This dart is diagonal. It folds down and towards center.
This is what darts do: they make flat fabric (or paper) not flat. Once the dart is sewn, the fabric can never be flat again. We want this because the bodies we are trying to fit aren’t flat.
Double Check: Your center fold from your dart should be on the center line you drew in earlier. If it’s not really close, you need to double check your line and your fold. One of them is incorrect.
Crease the end of the dart up to find your dart jog.
If you have simple dart that does not cross any other edge of the sloper, you can skip the next step.
Our dart jog here also crosses the bottom edge of the sloper. We need to fold along the bottom edge of the sloper. This is so that the dart jog does not end up longer than the bottom of the bodice.
If the dart jog does not cross any other lines of the sloper, it makes a shape like a tent or a weird A.
When the dart jog does cross another line of the sloper, it makes a shape like mountains or a weird M.
That cutout in the middle of the dart jog represents the part of the dart that would have gone past the waistline. The second fold lets us find that so we can trim it out of the final pattern.
The text shows you to just add seam allowances on darts like these. That’s a good idea for bulky fabrics. This method is good for lighter fabrics, like our muslin. Since we don’t end up with a seam allowance inside the dart, we don’t have to do any special finishing to prevent fraying.
Complete your dart by drawing in the new dart legs from the dart point to the corner. Remember, the dart point is not the bust point. It is the point you drew on the center line, 1/4″ away from the dart point.
Secure a sheet of tracing paper over your blue paper. You will be completing the pattern on your tracing paper. First, draw exactly around the edges of the sloper and the new dart you just made.
Put a piece of plain paper under the tracing paper. Make sure you see the whole outline and the dart.
Remember to square up corners. Your teacher can spot unsquared corners from across the room, sometimes without even looking. It’s like a Spidey-Sense(tm).
Add and label your seam allowances. For your samples, your grain line should be parallel to your Center Front line. Add it to the pattern, with your pattern markings: Your Name Sample Dart (#sample set number), and the number to cut. Cut 1 Self when on the fold, Cut 2 Self when on the straight.
Observance Test: there are two errors in the picture. One is something not marked, and the other is something marked incorrectly. Can you spot them?
When you notch your dart legs, the notch should be in line with the end of the dart leg. Sometimes it looks weird, but the notches are going to be matched up at the edge of the piece when it’s cut.
After turn-in, your samples should be kept in a 3-ring binder (behind the original sample sheet). This gives you a good supplement to your book, so you can see how you did the manipulations and finished the patterns discussed in the book. The book often shows only the manipulation.