Adjusting for erect posture

[Gerry]

I'll let out some CB to move it into darts. There's quite a bit inlay gathering now as you can imagine!

We may be at cross-purposes here, Robb. What I meant was to lift some of that cloth, vertically into the waistband. About a quarter of an inch and only in the middle of the panel/pattern, effectively creating a slight 'smiley' to the waistband seam on the pattern. As mentioned before, the area immediately to the side of the CB should be left as straight as possible. If scooped there, the CB ends up being pulled into the waistband, creating a wedgie if we're not careful.

A quarter might not sound like much, but it can make a huge difference. This is a screen grab from an old fitting video of mine (low quality, so the image is poor, sorry). Both legs have a 5/8th wedge taken out just under the crotch line, but the LHS has been picked up in the middle by a quarter and pinned in place. Note the difference.



To create a nice fall from the prominence of the seat, a slight pull on the backs is acceptable. Anymore than shown, however, creates prominent vertical drags (as seen in your photo with the seat pinned), which can create tightness when bending/sitting, amongst other problems.

I have a very straight posture, BTW.

[Robb]

We may be at cross-purposes here, Robb. What I meant was to lift some of that cloth, vertically into the waistband. About a quarter of an inch and only in the middle of the panel/pattern, effectively creating a slight 'smiley' to the waistband seam on the pattern. As mentioned before, the area immediately to the side of the CB should be left as straight as possible. If scooped there, the CB ends up being pulled into the waistband, creating a wedgie if we're not careful.

I think I got what you mean. I drew some rough lines on the pattern to reflect the changes. (I erased the front part lines for clearness)

The blue line is where I currently basted the waistband at. And I think what you meant for the smiley is the red line?

The green line is how much I roughly took out of the CB. I made sure it was square with the waistband on the toile (blue line) to avoid a chevron shape but that took out most of the angle of the seat seam.

[Gerry]

I think I got what you mean. I drew some rough lines on the pattern to reflect the changes. (I erased the front part lines for clearness)

The blue line is where I currently basted the waistband at. And I think what you meant for the smiley is the red line?

Not quite, Robb. Point 23 remains untouched. Probably point 22 as well: sometimes a little adjustment is needed there to maintain a nice, even run of the waistband (in that photo I posted, the SS was picked up by an eighth).

This is exaggerated for clarity, but the line should look similar. A subtle, curved dip (hence my use of the term 'smiley') in the middle of the panel, yet straight as possible at the CB.



All we're doing is pulling a small amount of cloth up into the waist, just over the fullest part of the seat, to get a cleaner fall. In conjunction with a wedge lower down, it helps to clean things up. What we don't want is to reduce the height of the CB. Nor scoop things there. Both will result in the seat being pulled up at the CB, creating a wedgie.

It's best to pin things to do this. Don't alter the draft then take it to the cloth, it should be the other way round.

[Robb]

Not quite, Robb. Point 23 remains untouched. Probably point 22 as well: sometimes a little adjustment is needed there to maintain a nice, even run of the waistband (in that photo I posted, the SS was picked up by an eighth).

Ah! I thought a smiley across the whole of the back, from sideseam to sideseam.

[Gerry]

Ah! I thought a smiley across the whole of the back, from sideseam to sideseam.

As with all with modifications, don't go overboard with this. It should just be a subtle curve, no more than a quarter inch dip in the middle. Any more than this and you'll likely pull down the waistband and/or create strong vertical drags at the backs of the legs.

Also, only do this on the need-to basis: if your wedge doesn't totally clean things up.

[Gerry]

In a way molding the shape of the CB seam to the shape of my back?

Note that in your draft illustration, the CB kinks at points 8/L (on the original draft - it looks more like a three on your revised diagram) to 23, towards the side seam. This, effectively, is a small dart incorporated into the CB seam, to better shape the small of the back. In your adjustment (shown as a green line) you possibly omitted this.



Edit: Because you have a flatter backside, it's not as critical to incorporate this 'dart', I was merely making you aware that those points on the diagram are another place where an adjustment can be made.

[Gerry]

As with all with modifications, don't go overboard with this. It should just be a subtle curve, no more than a quarter inch dip in the middle.

You can go up to 3/8ths, but that would be maximum IMO. Best to start with a quarter (if this mod is required).

[Robb]

Edit: Because you have a flatter backside, it's not as critical to incorporate this 'dart', I was merely making you aware that those points on the diagram are another place where an adjustment can be made.

I was sort of aware of it. I noticed many of the patterns I've looked at had a slight curve inwards at that point for the hollow of the back. But I never thought of it to see it as another dart. A revelation.

I appreciate the insights!

[Gerry]

I noticed many of the patterns I've looked at had a slight curve inwards at that point for the hollow of the back. But I never thought of it to see it as another dart.

The CB 'dart' also helps to compensate for inadvertent ease added at the apex of the actual darts. When factoring-in darts we simply add a little width to the waistband, only to take it out again. There's no net gain/loss once the dart is made-up, the darts merely aid cloth to curve in two directions: vertically over the seat and laterally around the body. This is all very well, but after adding width for the darts the side seam needs to be redrawn from/to the next reference point down, which is the seat line. So technically the darts should extend down to this line too in order to fully take-in the extra width we added.

In the draft shown, the guide-line for drawing the darts does extend down to the seat line, but not the actual darts, which is normal. To take things down that far would look poor, aesthetically, and with such a slither of cloth towards its apex, the dart could be tricky to sew. We therefore terminate the apex early, meaning that we inadvertently add a tiny amount of extra width/ease below the apex: the full intake of the dart isn't realised. This can result in a lateral 'ripple' of cloth/ease around the apex line. It's often compensated for, or can be compensated for, by treating the CB as a dart: note that the apex of its 'dart' does extend down to the seat line.

With low rise trousers the problem is a lot more noticeable. The CB is usually drawn as a straight line and it's more difficult to incorporate a credible dart into the draft. The 'solution' to clean up the back if things look a little rippled, is to take in the waist a little, which results in tightness. However, in my experience it's often better to leave out the darts altogether. In fact I've done A-B comparisons and invariably the 'no-darts' versions are cleaner.

It's all very well people on you tube demonstration the principles of darts using card, but to state the obvious, cloth isn't card. Yes, those principles hold with coat makers, because the cloth is backed with canvas, making it relatively inflexible. Otherwise, cloth will actually bend in two directions, though obviously more subtly if curvature is more pronounced in one direction (say, vertically over the seat). Still, there's enough curvature laterally for darts to be omitted altogether with low-rise trousers (and only low rise: darts are required to shape the small of the back with higher-rise trousers).

Maybe I'm a heretic, but darts really don't do much in low-rise trousers (other than cause problems IME).

Edit: though I use a drafting system that allows for this. Conventional drafts will probably end up with a little more curvature of the side seam if darts are omitted. It's all swings and roundabouts.

[peterle]

First I like the unpinned version much better. The fronts fall much nicer and the waistband is a bit more horizontal although a bit strange. A slight looseness under the seat is necessary for every trousers, otherwise sitting and stepping stairs will be difficult. Also the pinned horizontal dart is much too high wich throughs off the whole balance completely. The darts should start at point 24 and rise a little towards the seat seam. And it should take out a lot less.

I also want to adress the waistband. It is very slanted. Very high at the front and dipping at the back. Do you want it that high in the front? You said you did a stout figure alteration wich usually consists of adding width and raising the fly point.A pic of the front alteration would be nice. Lowering the waistline towards the fly point will most likely improve the run of the waistband.

The green line in your posted diagram shows you took out a very lot at the seat seam. This had two consequences: it reduced the back hip width and produces a very vertical seat seam run. Both is probably necessary. But it throughs off the balance.
My approach would be: starting with the original seat seam line I would reduce the whole seat slant with a dart like your first alteration diagram. (Starting at point 24!)This alters the whole top back angle, not just the seat seam angle. Then in another fitting I would determin wether I have to reduce the back hip width also by pinning a long vertical dart along the crease line. The pattern would be altered by slashing the undersides vertically and pinching the surplus.