HOW TO DRAFT A PANT TROUSER PATTERN

Hi hiveians.

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Happy Friday, Wishing you a weekend filled with fun and happiness.

TAKING MEASUREMENTS

The key to sewing clothes that fit properly is taking accurate measurements.

Taking the body measurements for a pants pattern
Taking body measurements is the first step in the process. It is very important to take accurate measurements. If
they are not accurate, it might influence the final result significantly.

Measurements and calculations for drafting a flat pants pattern:

¼ Waist

Measure the waist at the smallest. Or, if you prefer the pants standing lower on the hips, measure that circumference. Divide it by 4, because we are going to work with 1/4 of the pants details.

¼ Hips

Measure at the widest part of the hips. Again, divide this number by 4.

Crotch depth/rise

You can get this measurement by sitting on a chair and holding a ruler next to your hips. Measure from the chair up to where you want those pants to stand.

Hip depth

This is the distance between the waist and the hips you just measured.

The magic formula. To draw the crotch curve, we will need to know how far we should extend it on both the front and the back pattern detail. There is a simple formula to help us with that.

Front crotch extension formula: Back crotch extension formula:

15% of ¼ hip # 45% of ¼ hip

Or, once you’ve calculated the front crotch using the formula above, just multiply it by 3 to get the back crotch.

Length

Measure the overall length of the pants on the outer leg. Start from the waist (or a bit lower if you prefer lower-rise) and measure down as long as you want the pants to be. ..

Let’s begin the construction of the pants. The front and back pattern will be drawn side by side:

DRAFTING THE PATTERN

The pattern will be drafted in 2 sections. There’ll be one section for the back, and one for the front. These sections will then be cut on doubled fabric, so you’ll have 2 back pieces and 2 front pieces.

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TROUSER FRONT

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Take your pattern paper and down one edge, draw a vertical line the same length as the distance from your waist to your ankle. If you are making trousers for yourself, you might need to stick pieces of paper together.

On that vertical line, mark on your waist (that’s at the top), distance from waist to hips, your rise, and waist to knee.

Now you’re going to draw on the horizontal lines. These will go where you marked on the vertical line.

Take your waist measurement and divide it by 4. Add 1 cm for ease and draw that line at the top of the vertical line.how to draft a trouser pattern

Take your front hip measurement and divide it by 2. Add 1 cm, then draw that horizontal line where you marked your hips.

Underneath that, where you marked your rise, draw another horizontal line the same length as your front hip measurement.how to draft a trouser patternThis line will need to be longer, so we have to calculate the crotch extension (I wish they’d call it something else!). How long was the line you just drew? Multiply that by 0.25, then extend the rise line by that amount.how to draft a trouser pattern

Now find where you marked your waist to knee measurement on the vertical line. Divide your knee measurement in half, and 1 cm for ease and draw it on.

At the bottom of the line, draw a last horizontal line. This will be the width you want the trousers to be at the bottom.

Now join the lines up! The waist to hip line will be straight.how to draft a trouser patternThe next part, the hip to rise, will need to be curved. For this you can use a French curve, or a plate will do if you don’t have one.how to draft a trouser patternThe rise to ankle will also be a straight line.how to draft a trouser pattern

To position the fly shield in place, place the straight edge of the fly shield over the left fly extension, and align the top of the fly shield with the waist of the pants. Pin the fly shield in place so that when it is sewn with a 1/4″ seam allowance, the stitch line will just catch the left zipper tape.

Don’t worry about joining it to the knee line. Just make sure that you don’t go through that line, or you’ll have issues getting your trousers on!

Before I draft the back pattern I want the trouser to have side pocket

How to make side pocket

Take 2cm away from outer trouser front pattern curve, mark 3.5inches from side seam and mark 6inches down the side connect the line together for an open pocket side then cut it out.

DRAFTING THE TROUSER BACK

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Drafting the back section is done in exactly the same way as the front, with 2 exceptions.

The first is that where you draw you hip line, you will need to use the measurement you took around the back of your hips, divided by 2, plus 1 cm for ease of wearing.

The other exception is that to work out the crotch extension, you will need to multiply the hip line by 0.3.

ADDING THE SEAM ALLOWANCE

You will need to add a seam allowance to your pattern pieces. You can either draw around your pattern piece to add a seam allowance, or you could just add it in when you’re cutting out.

thanks.

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