Sunday, February 12, 2012

Pant Settings, the experiment

A recent discussion on a pattern-drafting chat list got me to thinking about pant setting choices in PMB. We have been told that we are to use the ROUND crotch shapes and a "level" waist when making the basic pants when we begin the pant fitting process.

I don't generally use the ROUND back crotch shape (although I do use the round front shape). I use the Flat bk shape, plus several other setting choices that differ from the basic, default shapes that they want you to use to fit your, the "Wild Cut".

The WILD CUT is Wild Ginger's name for the shape that basically adds a 'wedge' to the back pattern. Here is the difference between using the WC and not using it:

As you see, the back waist is higher at the center and is basically 'shifted' laterally, creating a more-angled center seam and a straighter side seam. This changes the relationship between the leg's centerline and the waist's center point.

Also, as I said, I use the FLAT back crotch shape, not the round one.
Here, you can see the difference in these two crotch shapes.

The RED pattern has a ROUND crotch shape in both front and back.
The BLUE/GREEN pattern has a FLAT crotch shape in both front and back.

You can see that the FLAT front adds a little width at hip level in the front, making the center seam a bit more angled. In BACK, the FLAT shape adds quite a bit of width to the pattern at hip level.

Now, if you use both the Wild Cut and the FLAT back crotch shape, there is a marked difference in the shape of the back pattern:

This pattern (using WC and Flat back shape) would provide more 'bum room'...both vertically and horizontally!

But for some reason, I decided to try making pants using the ROUND crotch shapes. I haven't sewn a new pattern for pants since version 3, although as far as I could tell, the pants drafted the same as before. But tech support had stated that the new ROUND crotch was more like the old flat one (my eyes couldn't see it) I decided I would give it a try.

There was an article on Fitting Pants by Karen Howland in the Dec/Jan 2002 issue of Threads magazine (issue 98, pages 24-26). This dealt with those \_/ wrinkles that occur in the back of pants when the pattern's waist tilt is not right for the body.

Her example is that of a hold a towel by two corners and let it hang. If both hands are held at the same height, the towel will hang smoothly. But if one hand is held higher than the other, both sides will still hang straight but you will see wrinkles in the towel. The top and bottom are now at an angle.

Apply this to pants--Even if the pants are cut with the center line perfectly aligned with the fabric's grainline, the pants will only hang wrinkle-free if the upper support (i.e. waistline) allows them to. The LENGTH of the pant at side and center must be appropriate for the body shape. When the back wrinkles look like \_/ , then the sides are not long enough...OR, the center is too long...for the body shape.

So theoretically, we could apply her instructions to PMB to determine our waist tilt, right? That is, if I measure from my body's back waist to floor, side waist to floor, and front waist to floor, then apply that to the pattern, the resulting pants SHOULD have the correct waist tilt, right?

Now, we all know that using the Wild Cut will add extra length to the CENTER of the back pattern. What about that? Do we need to use the waist drops to eliminate that back height or leave the extra height there, even though the pattern will now be LONGER than what we measure? I wanted to know!

I also measured my crotch LENGTH...between legs from front waist to back waist...while wearing pants that I liked the waist tilt of. I measured from the waist line of those pants to the floor when taking my vertical measurements, so the resulting pants should have a waist tilt that hit me just like the waist of these pants...that was my hope.

According to the article, you adjust the pattern's length first, getting the waist tilt correct. Then you look at the pattern's crotch length and lengthen the crotch extensions until the pattern's crotch matches your measuresments. Sounds easy enough, right?

Ok, so I have the numbers I need to evaluate my pattern.

I have:
• Waist to Floor measurements (front, back and sides…41.5”, 42.5”, 42.5” )
• Crotch length measurement (to desired waist tilt…26.5” )
• Inseam measurement (to floor…32” )
• Crotch depth (calculated from sideseam and inseam…10.5” )

But there are a couple of other extra numbers that need to be noted when measuring…these are HELPING measurements.
• When measuring the crotch length, determine the forward-backward placement of the crotch point, and note the front crotch length and the back crotch length separately. These should add up to equal the total crotch length, of course!
• Measure down the sideseam to the level of the hip depth--do this while still wearing the comfy pants and using THAT waistband to measure from. You want to know how far below THAT WAIST that your hip depth should be. I just looked in the mirror and found the level that my bum protruded the most (side view) and measured to that level.

Ok, so now in addition to the measurements above, I now have my helping measurements:
• Front crotch length--12”
• Back crotch length--14.5”
• Hip depth on pattern--8”

Here is what I did:

I created a new chart that used the DESIRED CROTCH LENGTH instead of the CL that was taken according to the WG instructions (measured to bodice waist). My DESIRED crotch length was 26.5” (instead of the 29” CL that reaches the bodice waist).

In theory, using zero waist drops and settings, this should draft a pant with an accurate crotch length for my body--that is, 26.5”.

In theory. Turns out, this is kinda variable! Even with all settings at zero…crotch extensions, crotch breaks, waist drops--the crotch length was 27.22”. Hmmmm.

So I looked at the HIP DEPTH. I compared hip depths from 8.5” to 7.5”. The crotch length varied from 27.22” to 26.6”. I return my HIP DEPTH to 8” because that is my desirable/helping measurement. At 8” hip depth, the crotch length measured 26.9”. This means my crotch length is about .5” too long (26.9, when I need 26.5).

Next, I look at CROTCH DEPTH of this pattern.
Draw a line perpendicular to the grainline across the BACK pattern from the top of the inseam to the sideseam. Measure the vertical distance between this line at the sideseam to the SIDE/WAIST point. That is the crotch depth of this pattern.

My pattern’s crotch depth was too long--11” when I need 10.5”.

In PMB, to change the pattern's crotch DEPTH,
• You can first look at what you have selected for the crotch EASE. Increase or decrease the crotch EASE to raise or lower the crotch level.
• If you are already at zero crotch ease and you need to shorten the crotch depth further, you can use the waist drops. Drop front, back and side waist EQUALLY to adjust the crotch depth.
• Or, you can reduce the CROTCH LENGTH measurement in the chart.

For now, I leave the crotch as is, and continue to compare other areas of the pattern.

I check the INSEAM length. The FRONT inseam was correct, but the back inseam was .25” too long.

I check the SIDESEAM. The length of the sideseam needs to match my SIDE/WAIST-TO-FLOOR measurement. My pattern’s SS is too long--I measure 42.5” but my pattern’s SS is 42.9”.

Note: I am NOT clicking on the side seam segments to measure--I am drawing a straight line from sidewaist to level of hem and measuring that straight line. This is because I measured straight down to floor--I did NOT follow the contours of my body when I measured this. FYI, The difference in the straight-line measurement and the actual seam length is about .25”.

So, this sideseam was about .5” too long--the same amount that the crotch depth was too low.

The TILT of the waist will be determined by the waist to floor measurements.
In my case, my side- and back-to-floor measurements are EQUAL but my front-to-floor is 1" shorter.

Now I look at the pattern--again, I draw a straight line from the CB/waist point to the hem level and from the CF/waist point to hem level to measure these distances.

I have chosen the WILDCUT, so I know the pattern’s center back waist will be higher than the side waist (and it is--by about 1”). My pattern measures 43.8” CB TO FLOOR (hem) but I need 42.5”. So, my pattern’s CB waist is about 1.3” too high--which is MORE than the amount that the side-waist and crotch depth need to be lowered.

The front waist on my pattern measured 42.9” from hem--I need 41.5”. That means I will need to lower the front waist by about 1.5”.

Now I have the numbers.
Using the waist drop tool, I need to lower-
• the SIDE-WAIST by .5”,
• the CB-WAIST by 1.25”,
• the CF-WAIST by 1.5.

Ok, so now I remeasure from these points to the hem, and now my pattern’s waist tilt matches my body’s WAIST TO FLOOR measurements.

The CROTCH DEPTH is now correct.

But what about the CROTCH LENGTH? It is now too short--24.5” when I need 26.5”.

Well, according to Karen Howland in the article I am referencing, the next step is to increase the crotch extensions.

I have recorded the separate front and back crotch lengths, so I can compare these separately.
My target FRONT crotch length is 12”--the pattern measures 11”. I need 1” more.
My target BACK crotch length is 14.5”--the pattern measures 13.5”. I need 1” more.

After increasing the crotch extensions by 1” each, the total crotch length measures 26.38”. That is pretty close to the 26.5” target.

Now, something else to think about. I took my BACK waist to floor measurement straight down from the hip--but I want my pants to cup under my bum a little. So, that CB-to-floor measurement COULD be increased to allow for extra fabric to contour under the bum. So, I raised that back waist up by .25”--in essence, increasing my CB-FL measurement to account for the contouring, which means I would only need to lower the pattern’s back waist by 1”, not 1.25” as I originally did. Doing this makes my CROTCH LENGTH measure 26.64”--better!

So now the pattern reflects my measurements. The crotch depth is right; the crotch length is right; the side waist to floor, CB-FL, CF-FL are all right.

Now, I rechecked the INSEAM lengths. The FRONT inseam is now too long by 0.125”, but the back inseam is now .299” too long. I will change that manually, trimming the top of the inseams at the crotch points.

However, the legs are much wider on these pants now that the crotch extensions have been lengthened.
• My patterns measure 28” across the top of the thigh area (at crotch level).
• My own thighs measure 23” at the top.

I decide to give them a try, and print the pattern.

Here is the back can see that the waistline at the side and center are about the same 'height'. Notice that back side-thigh area...see how I have redraw the sideseam and marked (in red) the amount I wish to remove? Remember, on the NAVY pants I just finished, remember how I said I kept wanting to grab a wad there and remove it? WEll, at this point I still had not had my 'lightbulb moment' I was just going to reshape that seam (and did).

Notice how wide that back body space looks! Also notice the note on the pattern...the back inseam is too long and must be shortened so it won't be longer than the front inseam.
I had a bad feeling about this pattern. Before commiting to fabric, I tried out the front pattern on my body. I aligned the center line down the center of my leg and compared the waist and center front seam. Oh my! This front seam is about 2" farther toward the side than the seam on the pants I am wearing! This tells me that this isn't going to work...this pattern's front crotch extension is way too long! Shortening the front cr.ext. will move the leg laterally as compared to the waist and hip.
I was also skeptical of that waist tilt in front. It was scooped way too low! So, I shortened the front crotch extension AND raised the front waist drop. This kept the length of that front crotch seam stable, but it DID change the waist to floor measurement. oh well.

I went to fabric and cut, using 1" seam allowances for the sides and inseams.

These pants didn't look awful when standing but sitting was painful and very difficult! Plus, there was still too much fabric in the front in my lap. The legs were pretty wide.

Overall, the waist tilt was pretty close to correct. The sides are a little higher than the back, though, which answered the question about the Wild cut! No, you should NOT lower the back waist to make it match the WAIST-TO-FLOOR measurement if you are using the Wild Cut!

So I went back to the computer and redrafted the pattern...this time, moving the sideseams forward (-.5) and reducing that front crotch extension from (+.5) to (-.25).

The front looked better, but now sitting was even more difficult....despite that fact that the back crotch extension was (+1).

Remember, I had decided to use the ROUND crotch shape for this exercise.
And I was feeling it!
These pants were tight across the bum at hip level.
Like a sports know how a sports bra will kinda push both boobs together, rather than lift and support each breast separately? Well, that is how these pants it was giving me a uni-butt! My cheeks did not have enough coverage, separately.

These pants were just too straight up and down! No bias...

I redrafted again and printed a new pattern to recut these pants once more. At this point, I was out of seam allowances...down to 3/8" s.a.s, which is what I usually use on pants that I KNOW will fit!

Although difficult to see, I had drawn the hip line on these pants (FRIXION erasable gel pen from Pilot...wonderful marker, it disappears with a touch of the iron!). As you can see, once you cut a FLAT crotch shape, which is slanted, the hip line meets the center line at more of an angle. This means this line will NOT be level when on the WILL have a slight 'V' shape, just as it shows here.

Because the last iteration was SO tight across the seat and thigh when I sat (despite being fairly wide in the thigh area!), I decided to try using the Flat FRONT crotch shape. I had not used it previously...I always use the ROUND front shape. But someone else on the chat list mentioned that she needed to use the flat front shape, so I thought I would give it a try.

Well, stupidly, I put the fly zipper into that new pant front BEFORE testing the fit of the FLAT front crotch shape.

Uh oh!

It was awful. These pants were SO baggy across the front hip area! Look at those folds!

Pinching out the front crotch made them look better. Too bad I couldn't just resew that area smaller (like it would be if I had used the round crotch shape)...BECAUSE I HAD INSTALLED A STUPID FLY AND ZIPPER!!!!

Needless to say, I was pissed.

They were starting to look better in back, though. There was more room for each bum cheek now.

As luck would have it, I had just enough fabric to cut out another pair of fronts.

But I HAD to make this existing back work, though...there wasn't enough fabric to start over with both pieces.

And it was obvious that I needed to extend that back crotch even MORE than it was extended on this pattern. Hmmmm..... how could I do that, as I was out of seam allowances?

I decided that if I moved the pattern's sideseam BACKWARDS in my settings, the new front would be wider and the back would be narrower. And I could fit this narrower back on the old back fabric to recut (if I didn't mind making the lower legs slightly narrower...which was fine!). The new wider front could be cut from the remaining extra fabric. The front would be wider than usual, to make up for the back being narrower. Seemed like it might work.

(Now, this is NOT what I usually do. Normally, I would move the sideseam FORWARD. But to be able to use the back pattern that was already cut, I had to do this)

So that's what I did.
The new front had a ROUND crotch shape with the crotch extension SHORTENED (-0.5").
The new back has a FLAT crotch shape with the crotch extension LENGTHENED (+0.75").

(BTW, I used the WILD CUT for ALL these various iterations.)

This new one seemed good. After all, I am practically back to using the same settings I had used in the past, in Version 3!

With the wild cut and flat back crotch, I could sit in these pants. The longer back crotch extension combined with the shorter front one put the inseam at the right (more-forward) location.

The upper side seam, though, was a bit more towards the back than I desired, but I didn't change the ss placement AT and BELOW the knee (so the lower leg section was still cut as if the SS position was a (-.5), which is my desired SS location...I just joined the two patterns together at the knee) so the overall look of the pants from the side view is fine. No one would notice the more-backward upper sideseam if I didn't point it out.

I thought this was gonna work.

However, it was just a bit too tight across the upper back area. Moving the sideseam backwards makes the back darts smaller. I need back darts that are bigger! THAT is a major reason for moving the sideseam forward! make larger back darts. These smaller darts needed to be sewn larger...and once that was done, there was a gap in the side seam.

Below, you can see the difference between the pattern I started with (in RED) and what I ended up with. You can see that as fabric was removed from the center back to angle that seam, it needed to be added to the side back. Well, I only had 1" of seam allowance to work with.

So I made the painful decision to cut off the top of the back of these pants and replace it with a yoke! I figured I could cut the yoke WIDER to replace the missing fabric!

Here, you see the little vertical 'wedge' I added at the side seam (to the right). I cut this from fabric and crossed my fingers! I wondered how this shape would look on my behind. Would I suddenly look like SpongeBob Squarepants? Or SquareButt?

This was a last resort to save these pants.

Funny, because this fabric had already been relegated to the give-away bag. I had put it there, thinking I would not use it because it was 'scratchy'. Well, it isn't scratchy. And now I have become attached to the outcome of this experiment, determined to end up with wearable pants!

I took a deep breath and cut off the top of the pant back...


SueC56 said...


Sometimes I have to concentrate really hard to follow all your details, but I love the analysis. I'm anxious to see how this works out.

Marilyn said...

Okay, I'm exhausted now and must go back to bed. I personally think those pants looked great and applaud your tenacity in getting the perfect fit.

Anonymous said...

Your blog is "Priceless".
Thanks so much for the time you spend to give us such great details. (PMB)
I know your pants will fit great!
Rosemary (RJ388)

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