Monday, January 26, 2009

Pattern Chat!

And now for some pattern chat…

This might be too long and boring, so if you're just after pretty pictures, scoll down to the previous posts! :)

I have been working on perfecting the fit of my bodice patterns using PMB for quite a while now. The solutions to my fitting issues have been elusive, but I AM making progress! As mentioned before the division of waist reduction has been a stumbling block for me. I knew I needed my back waist darts to be larger than the front ones, but HOW to accomplish that has eluded me. Well, not anymore!

The tool I am discussing is the Sideseam Placement Tool. In version 4, this is found on the Settings Tab.

Using my measurements, this is how the program drafts the basic Torso block (blouse) if I leave the sideseam placed at the zero position.

The Hip and Waist are divided equally, front to back, but the front pattern is over 2” wider than the back pattern at Bust level. This makes for an interestingly shaped pattern! There is hardly *any* indentation at the waist on the back pattern. Imagine trying to sew those F and B sideseams together!

The back armhole has very little width to it, while the front armhole is very large. This creates a sleeve that has a longer front cap seam and a shorter back cap seam…it looks backwards and restricts arm movement.
I don’t want my patterns to look like that! So the first thing I do is use the Sideseam Placement tool to move the Side/Arm Point toward the front (a negative setting). The maximum amount the SS can be moved is 1”…but remember, my front pattern is 2” wider than the back pattern at underarm level! Moving the Side/Arm point the maximum amount (-1 setting) reduces the difference in pattern widths (at underarm level) to 1”. That is the best I can do. This greatly improves the armhole shapes on both patterns and balances the shape of the sleeve.

And with the bust dart in the SIDESEAM position, the widths of the front and back patterns at underarm level are nearly equal!
This setting change alone makes sewing those sideseams a little more ‘doable’! However, both Front and Back sideseams slant toward the front at hip level. The angles of the Front and Back sideseams do not have the same relationship to the grain line…they are not ‘mirror images’. I prefer that my sideseams be mirror images…I think it improves the hang of the garment when the grain is identical on each side of the seam. Plus, I always felt like my back waist darts needed to be larger than my front ones…I have a belly at the front waist, but the back waist goes in quite a bit, just as, at hip level, the bum sticks out way farther in back than in front! So I had to figure out a way to achieve this balance with my patterns.

Enter the Sideseam Placement tool again! This time, it’s the Side/Hip Point.

Now, this one took a LONG TIME to figure out, because the required setting was NOT intuitive! Moving the S/H Point forward (negative setting) makes the back waist darts larger…which was part of my goal…but it also compromised the indentation at waist level on the back pattern. Boo hiss. Or, I could improve the waist indentation by moving the S/H Point the other way…backwards (a positive number)…but that made the back waist darts smaller and made the front waist darts become way too large! It seemed that I could never hit on just the right combination to achieve BOTH of these goals…they seemed at odds…and this flaw showed up in my garments as pulls from the sideseam or the waist darts at waist level.

The real clue came by analyzing my superimposed patterns with the bust dart placed in the SHOULDER position. Even though moving the S/Bust Point forward makes the patterns almost equal in width at underarm level when the bust dart is in the sideseam, they are NOT equal in width with the dart in the shoulder position.

I began to consider that since the front pattern was wider than the back pattern at underarm level, the only way to get mirrored sideseams was to make the front pattern wider than the back pattern ALL THE WAY DOWN. This means I HAD to change the hip!

So, in a nutshell, here is the deal...and this is for *ME*, not necessarily for all...

Because my bust is large, I need to use the maximum S/A movement to better divide the armholes, and this makes the front and back patterns almost *equal* in width at underarm level WHEN THE BUST DART IS IN THE SIDESEAM.

However, once the bust dart is rotated into the SHOULDER position, it is apparent that the patterns are NOT EQUAL in width at underarm level after all...the FRONT pattern is 1" wider than the back pattern.

So I move the S/H point, too (backwards), so that the front pattern is now 1" wider than the back pattern *all the way down the sideseam*...from underarm to hem (the front is wider and the F&B sideseams are mirrored/identical...same waist indent on both).

I *need* this extra width on my front pattern at bust level...but NOT at waist and hip level.


  1. I do need for the sideseams to be mirrored, and
  2. I do need for the front and back to be equal in width at hip level.

These two things seemed at odds with each other. In order to get mirrored side seams, I HAD to move the S/H point backwards...but by doing so, that made the hip distribution *unequal*. So, my solution was to INCREASE THE HIP EASE until the back pattern was as wide at hip level as it was BEFORE I moved the hip point (which means adding 2" extra ease)...then, manually remove the excess ease from the front.

After much experimentation, this is the pattern I have arrived at!

See how the sideseams, front and back, have the same relationship to the grainline, which is parallel to the center lines of the patterns?
You can see the relationship of my Torso Block to the red overlay (the Dress Sloper). Notice the relationship of the HIP LINES. The Dress Sloper is divided equally, front to back, at hip level. However, my Torso patterns are NOT equal at hip level. The front pattern is wider than the back at hip level and wider than the red overlay at hip level (see little circle and arrow)…and this is because I used the SIDESEAM PLACEMENT TOOL to move the Side/Hip point backward. I used the -0.5 setting, which makes the front hip 1” wider than the back.
Yes, that made the front waist darts much too large, and made the back waist dart not quite as large as it could be. So I used the SIDESEAM PLACEMENT TOOL to move the Side/Waist Point backwards, too, by 0.25” (half as much as I moved the Hip…again, a negative setting). This made the back waist dart just a little bit larger and made the front waist dart just a little smaller, yet had NO EFFECT on the indentation of the waist at sideseam (which is controlled by the relationship of bust to hip)…good! (The BACK waist dart size is what I was trying to control with this setting…the front dart is too wide no matter what, so I manipulate the size of the back dart with the S/W Point, and will deal with the front dart in a minute!)

Moving the Side/Hip Point backwards made the front pattern’s hip 1” wider than the back. Now, think of that in reverse: It made the BACK pattern 1” NARROWER than the front! I needed to regain some of that lost back hip width and prevent the back hip from being narrower than the hip width of the red overlay. So, I increased the HIP EASE by 2” (I added 2” because the pattern is only half the body…I needed 2” total…one inch additional hip ease for the left side of my body and one inch for the right side).

But adding this 2” Hip ease made the FRONT pattern’s hip larger, too…made it too large by one inch. And those front waist darts were still way too large. So the solution was to manually remove this added excess *at the front waist dart*! I offset the center line of the single front waist dart by 0.5” on both sides. I extended these lines to the HEM of the pattern (which in this example is at hip level).
Then I redrew the lower dart legs of the front waist darts from waist to HIP LEVEL…smoothing out the angle that is formed at the intersection of old dart leg/new line.
Basically, this is removing that extra 1” of front hip width that I added…but instead of removing it at the SIDE of the front pattern, as happens with ease reductions, it is removed from within the pattern…allowing the front sideseam shape to mirror the back sideseam!
The resulting front waist dart is much narrower below the waist than before, because now the dart is measured from the stitching line to the NEW center line(s), not the old one. The ‘effective’ dart width is reduced because the new lines removed a chunk of fabric all the way to the pattern’s lower edge, not just to a point within the pattern (see the diagonal pink lines).
The lower part of the new front waist dart is only 0.719” wide on each side of this new center line (blue lines)…for a total of 1.438” (much less than before, and still less than the width of the back waist dart!).
EVERY PMB Torso pattern will have to have this seam in front, whether a Princess seam or a waist dart that continues to the hem. But this makes the front and back pattern (after this alteration) be equal in width at hip/hem. However, any pattern with a waist seam will not have to have this seam/dart, as the gap can be eliminated by sliding the two pieces together.

These settings can also be found in Version 3…the difference is in the location of the SIDE/WAIST Point tool. In Version 3, this point cannot be changed on the TORSO blocks within the Drafter (blouses, jackets, sheaths, etc.). However, if you go to the SLOPER section, and navigate to the DEFAULTS, you can set the Side/Waist Point in the defaults for that measurement chart, and it WILL apply to the waist darts of the Torso drafts, too…for that measurement chart only.


cyro11 said...

wow Trish, thanks for explaining your manipulations. Might we see the blouse on you shortly/

Cynthia in UK

Trish said...

I don't do anything fast, but hopefully I'll get it done in this lifetime! And I'll be sure to share... ;)

Marilyn said...

So will all this make the fronts hang better with out having a seam down the front from the lower end of the dart? I remember you complained of having too much fabric in the lower front.

Trish said...

Not *without* the seam in front...that seam is necessary to this 'formula'. If I want to sew without that front seam, I can use a pattern where the waist and hips are exactly the same width,F&B, but the front bust is wider than the back (pictured above--the one with the S/A placement of -1, before I adjusted the S/Hip placement). That one is totally wearable but has the slight pull lines indicating a need for more fabric at the lower side/front. I am just looking for 'perfect'.

arlee said...

Yoicks! Though i'm a very experienced seamstress, this is why i wear tunics and ruanas for my generous "girls" :}

Shirley said...

Trish, You have a teaching blog. What you do can help others as well as myself. I just wish people could hear you in person. Shirley

Free Hit Counter