Sleeve block: How to start pattern drafting
As part of my pattern drafting series, I continue with a sleeve tutorial. I will show you how to draft a sleeve pattern from from scratch using your own body measurements. Creating your own blocks are a great way to ensure your garments fits you perfectly. Once your block is complete, you can then hack your pattern to sew any style you like.
Remember learning something for the first time can be tricky, but enjoy the process!
Tools you will need
- Pattern paper
- Measuring tape
- Pencil
- Ruler
- (Optional) Frech curve; this is a curved ruler that is used to draw round shapes such as the sleeve cap area in a pattern. Personally, I don’t use this very often and you can definitely follow this tutorial without it.
Body measurements
Shoulder to elbow
Bicep circumference
Shoulder to wrist
Wrist circumference
Note: I use this as my wrist measurement so when I sew my sleeves, it will fit through my hand.
Before you start
You probably would have noticed with shop-bought patterns, the instructions will say; “cut on the fold”. If a sewing pattern is the same on both sides, it can be divided in half lengthwise along the centre and cut on the fold of your fabric. So after you’ve un-folded your fabric, you’ll end up with the full pattern piece.
In this project, you will start by drafting the sleeve block on the fold. Once the pattern is completed, you will then make small adjustments to the sleeve cap. This is because the shape for the front and back sleeve will have a different curvature to accommodate the slope on your shoulder area.
This block is a fitted sleeve pattern designed for non-stretch fabrics. Pattern ease is not included in this tutorial and the sleeve will therefore fit very closely to the arm. Once the block is complete, you can then add ease or adjust to suit stretch fabrics.
After you’ve drafted the sleeve block, you can then add your sewing allowance.
Sleeve block tutorial
On your pattern paper, mark your shoulder – Point A and draw a straight horizontal line to Point B. The length of this line is your bicep circumference.
Next, measure the distance from your shoulder to your wrist. From Point A draw a vertical line to Point C, this is your sleeve length.
Draw a horizontal line from Point C to Point D to mark the wrist. For now, this line is the same length as Point A to Point B.
The Cap Height of the sleeve is the distance from the shoulder to the base of the underarm. Measure this distance, then draw a vertical line from Point A down to Point E.
Next, divide your bicep circumference by 2.
Formula: bicep circumference ÷ 2 = E to F
Starting from the centre fold line, Point E draw a horizontal line to Point F.
Measure the distance from your shoulder to your elbow. From Point A draw a vertical line to Point G, to mark your elbow point.
Divide your elbow circumference by 2.
Formula: elbow circumference ÷ 2 = G to H
Starting from the centre fold line, Point G draw a horizontal line to Point H.
Divide your wrist circumference by 2.
Formula: wrist circumference ÷ 2 = C to I
Starting from the centre fold line, Point C draw a horizontal line to Point I.
Using your ruler, draw a diagonal line from Point F to Point I.
Mark the half way point between Point A and Point E which is your cap height.
Time to draw the sleeve cap. The top of the sleeve cap will form half of a semi-circle, so that when it’s unfolded the top of the sleeve cap will have a semi-circle shape.
The bottom half of the sleeve cap will also form a half semi-circle shape but it will be flipped so the curve is facing the inside of the sleeve.
You are almost there! This is what the basic sleeve block looks like without ease and without seam allowance.
Now you can add your desired seam allowance. Do not add seam allowance to the center fold as it marks the middle point of your pattern block.
Right now, both sides of the sleeve cap look exactly the same. However, the cap needs to have a different curvature at the front and back to accommodate the shape of the armhole.
The red line shows the change I made to the back section of the sleeve. The top half of the cap needs to drop slightly whilst the bottom half has a less pronounced curve. This to help the sleeve lay in position when sewn to the bodice.
Redraw your seam allowance lines.
Add notches that will help you clearly distinguish between the from and back back of the sleeve.
For the front, I added one notch.
For the back, I added two notches.
Sleeve block in action
Final Thoughts
Congrats! Happy to see you at the end! Thank you for following along. Sewing is not an exact science and there are many different ways to draft which will achieve a similar effect. The technique I showed you above is what works personally for me. Whilst I hope this tutorial will work for you, follow your intuition and do what works for you.
you’re welcome to reach out if you have any questions or leave a comment below.
Want to continue your self-drafting binge? Click HERE to see my skirt block tutorial.
