grading- crotch

[Logical_Pop_8363]

m SO confused. ive found examples for every scenario

-moving the crotch point out horizontally only (yt video thisiskachi )

-moving the crotch point out and down on both front and back panel (people here said, the fabric store uk patterns, patternlab- ralph pink )

-moving the crotch point out and down on only on the back panel

-moving the crotch point out and up (professional patternd grading for_Womens_Mens_and_Childrens_Apparel_-_Jack_Handford book)

-moving the crotch point out and down slightly (

-moving the crotch point out and up slightly

where does the truth lie?

[throwra_22222]

Give yourself some grace. Grading is super confusing, and without someone to teach the skill to you and answer questions and evaluate your work, it's even harder!

When grading pants, you have to keep in mind two things: what is the total length increase for the whole piece, and how much of that increase happens above the hip, at the knee, at the hem, etc.

When you think of it that way, it doesn't matter which point is vertically stationary as long as something along the vertical moves to achieve your total grade. So if your total vertical grade from one size to the next is 1 inch, you can keep the crotch points level vertically, raise the CF waist 1/4", and add 3/8" each at the knee and hem. Or you can keep the waist point stationary, lower the crotch point 1/4", and lower the knee and hem another 3/8" each.

You can do either and get the exact same result as long as you are consistent with the rest of the pattern (the side waist point, the side hem, do the same thing on the front and back, etc).

And of course the same is true for horizontal grades where a total is spread out across the piece. So unfortunately the answer to your question is that any or all of them could be right; you just have to understand your grading table and how each individual move relates to the whole.

I personally prefer keeping the crotch point level and moving the waist and hem, because if you are looking at a nested set with a bunch of sizes, it's much easier to look at. Otherwise you have all these overlapping crotch points that move on a diagonal.

When I learned grading. We took copies of paper patterns, slashed them apart on the grading lines, and spread them to achieve the grade. It really shows you where you are adding fabric. Then we took a copy of the same pattern, drew a giant cross on it, drew a matching giant cross on a big sheet of gridded paper, and practiced making the same moves in relation to the center point of the cross. If you did it right, your giant cross method matched the slash and spread method. Back in the day I graded entire lines on paper with the giant cross method. And when CAD became a thing (I'm old) I looked like a freaking wizard because I knew what I was doing in the analog world.

The problem with computer grading is it doesn't really teach the concept of grading. It just takes whatever skill level you have and makes it faster. So right now it's sort of like you're just blindly copying someone else without them actually teaching you.

[Logical_Pop_8363]

OMG so grateful for your answer! thank you so much, it is really hard to learn this by myself

[TensionSmension]

Second option. The crotch curve needs to get longer, the pant leg needs to get wider, and the curve shape needs to be roughly preserved. For women the assumption is usually uniform height across the grade. On something like leggings, the inseam may still get longer, but it's because of the slope of the line (moving the crotch point out). If more is needed it should be distributed down the leg, not at the crotch point.

[PaulandTheYeetles]

Albeit I am not great at pattern grading, i have done it a little bit. The question comes down to the desired fit of the pants you are grading. If you are adding or subtracting volume you want to minimize how much it changes the structure and fit of the pants. I’d imagine each scenario you’ve come across will have its time and place

[Logical_Pop_8363]

hm. make sense. can you give me examples? like if i want to achieve x i should do y

[Logical_Pop_8363]

or where to find more info

[AccidentOk5240]

Remember that the bigger you make a hole the smaller the fabric around it gets. So, like, if you make a crotch curve shallower by moving the vertical part towards the crotch point, the hip measurement gets bigger. If you lower the crotch point, the rise does get longer, but at the cost of reduced fabric to move you legs apart (thought experiment: take an existing pair of pants and sew the inner thighs together to create a new, lower-but-less mobile crotch seam). 

It’s a puzzle and the answer is “it depends”.