Diagrams 4-13: Adjusting the Basic Sack Coat

Introduction

Finally, we’ve created the start of a sack coat pattern using the methods found in The American Garment Cutter. From here we still have a few adjustments and alterations before we can get to part where we actually start cutting some fabric and sewing it all together.

The first two diagrams are intended to confirm that the shoulder is, in fact, correct and what to do if it isn’t. The next series of diagrams show how to alter the basic sack coat for different styles and body shapes around the upper back and shoulder. All of these diagrams use the same set of basic measurements as before, with the exception of the shoulder or blade size.

The adjustments he advises for the basic sack can also apply for similar adjustments to other jacket and overcoat styles later in the book. So these methods will also be assumed as known to the reader later on as we dig through the rest of the text.

Diagram 4

Our first confirmation that everything is as it should be involves checking that the overshoulder as drawn matches the original measurement. This means lining up the fore and back parts so that the shoulder seams are actually touching.

Place points 11 and V together so that the two shoulder lines just touch one another without overlapping. Measure from L to B, this distance should be equal to the overshoulder measure plus 1″ extra.

On our diagram that’s 18″ and, indeed, it comes out correctly.

If everything is correct, shape the curve of the armscye a bit so that it’s smooth.

Diagram 4

Diagram 5

Diagram 5 shows what we should do if things don’t line up correctly. We rotate about point V so that Z starts to overlap the front part until line L-B is the correct distance. Then trim the shoulder seams to eliminate the overlap and reshape the armhole and neckline to accommodate this change.

Diagram 6: High Shoulder

This diagram shows how to create an exaggerated high shoulder. The first step here is to draw the line from A, where the gorge meets the shoulder seam, down to the bottom of the armscye. Then draw another line on the shoulder. Regal doesn’t exactly help locate this line, it’s just nebulously on the shoulder somewhere, roughly parallel to the shoulder seam itself.

Next we’ll open the shoulder, or just slice it, at point G. Open up or rotate about C so that F is about 3/8″ to 1/2″ above G, which is where it started. This will place E and D. Now connect those according to the dashed lines shown. Smooth out the neckline and armscye.

Diagram 7: Asymmetric Shoulder

Regal notes that not all bodies are perfectly symmetric. Sometimes one shoulder is lower than the other. When this is the case he advises that we draw our pattern to whichever side is higher. We can do this by cutting out the front and back pieces for the high side and then tracing them onto another piece of paper with the following adjustments.

On the low side, lower point 11 to 12 and point 13 to 14 by whatever amount the shoulder is asymmetric, Regal uses the example of someone who has one shoulder 1/2″ lower than the other and lowers these points by 1/2″ each.

Retrace the armscye from 14 to 12. At point 12 pivot the backpiece and trace out the shoulder seam so that the top of the seam, point 10 at right, touches the original seam line, labeled 9, and trace the neckline again. This will relocate the center neck, 7, to point 8, trace the rotated center seam until it intersects the original center seam.

Now simply raise the front hemline from 15 to 16 by the same adjustment, 1/2″ in this case.

Diagram 8: Shoulder Sway

Regal also notes that not all asymmetry is because the shoulders are actually asymmetric, but sometimes the body sways in a way that one looks shorter than the other even though they’re actually the same height. Despite the smudges on this page, the diagram is still readable.

Pattern out for the high side, again. One the low side block, split from 1 to 2, which is just outside of point N on our original diagrams. Mark point 3 below 2 at a distance equal to the asymmetry, the distance that the lower shoulder is below the higher one. Overlap 3 to 2.

This will push the center seam out at 1, bring it in to straighten it and then fill out the side seam out by the same amount. This shifts the whole back panel to the left a bit in this diagram.

Now split the front part from 4 to 5, which is on the same line as 1 and 2, and overlap 5 and 6 by the same amount as 2 and 3.

Diagram 9: Large Blade

This diagram has the same dimensions as the basic sack coat except with a 13″ blade instead of a 12-1/2″ blade. This slight difference will throw off the proportions of the coat without adjusting the way it is initially drafted. The main difference to note here is the appearance of the extra points, 23, 24, and 25 on the diagram. Otherwise everything is virtually the same.

We follow the instructions from Diagram 1 up to locating point L. Point 23 is exactly 3-1/2″ from point K, where we located L before, and point L is positioned the blade measure away from point 1 as before. M is halfway between 1 and L, as before. Point S is 1/2 the waist ahead of point 24, while Q and R are located by squaring down from L as before. We’ll shape the sleeve using the line coming up from L as before.

We also need to reshape the neck to accommodate the change, which is accomplished with point 25. From A to 25 is half the distance from L to 23, 1/4″ in our case. A to 8 is 6-3/8″, 8 to 9 is 1-1/2, connect A to 9 all as before in Diagram 1. From 25 to 10 is 1/6 the (half) breast and square up from 10 to locate 11. Shape the center back from 25 to F.

From L to V is equal to the strap measure plus 3/4″ minus the distance from 25 to 11. Everything else is finished as in Diagrams 2 and 3.

Diagram 9

Diagram 10: Small Blade

Similar to Diagram 9, this one has the same dimensions as the first three diagrams except for a 12″ blade. Again, this results in a slight alteration in certain proportions. This again involves locating the same extra points, with very minor adjustments.

Diagram 10

We once again follow Diagram 1 exactly up until we reach the point of locating L. This time L is placed as before, 3-1/2″ from K, and 23 is fixed at the blade measure ahead of 1. Square up and down to locate point Q and point 24. From Q to S is 1/2 the waist. M is halfway between 1 and 23. We’ll also be using the line coming from 23 rather than L to shape the armscye.

This time we move back from A to find point 25, rather than forwards. From A to 25 is again half the distance from L to 23, which is still 1/4″ for us. Shape the center back from 25 to F again. This time we’re going to measure the neckline from 25, so from 25 to 8 is 6-3/8″, 8 to 9 is 1-1/2″, and 25 to 10 is one-sixth the breast.

From 23 to V is equal to the strap measure plus 3/4″ minus the distance from 25 to 11. Everything else is exactly the same as in Diagram 3.

Diagram 11: Back Arm Fold

Adding a fold in the back of the sack is fairly simple, as shown in Diagram 11. We take the back piece and measure out from A to B by somewhere between 1/4″ and 1/2″ and reshape the armscye and side seam to match. Note that the point labeled “A” in this diagram is actually the point just to the left of P in the above diagrams.

After cutting out the piece, we’ll fold this extra bit of material back in and press it.

Diagram 12: Narrow Shoulder

A narrower shoulder can be achieved by lining up the shoulder pieces at the shoulder seam the way we did for diagram 4 and simply reshape the armscye slightly as shown in Diagram 12. Just place the French curve so that the new curve is smooth and fits the desired shoulder size.

Diagram 13
Diagrams 11 and 12

Diagram 13: Wide Shoulder

A wider shoulder requires a bit more adjustment than the narrower shoulder. Add an amount, from 1/2″ to 3/4″ to O to reach N. Use half this amount to find 12, B, and W by extending from 11, A, and V respectively.

From P to Q is 1/4″. Reshape the back armscye from Q to N.

Now line up the shoulder seam as in Diagram 12 and reshape through N to find Y.

Make sure to measure for the armhole for sleeves before making these adjustments.

Conclusion

We’ve made sure that the pattern fits properly and now we’re finally ready to put scissors to fabric. This, of course, is where Regal’s advice ends. His book is about drafting patterns, not sewing them, for that we’re on our own. We’ll need to look at some other sources later on to figure out our next step.

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