Sometimes I see sleeve patterns where the center point of the sleeve (maybe that’s not the right term I’m referring to the highest point of the sleeve cap) is not entered horizontally (compared to the sleeve width). I think I’ve seen it edged towards the front notch a bit more than the back notch but maybe I’m misremembering. Why would one do that?
The second question I have is regarding the sleeve width (at the base of sleeve cap that is not the sleeve hem width)… this is (generally) based on the bicep measurement right? In which case I wonder why I sometimes see short sleeve patterns with a difference in width between the bottom of the sleeve cap and the sleeve width considering that as far as I know they’re both based on the bicep measurement.
Oh and a third question… the slope of the front and back notch… what effect does this have on the eventual garment? I get that sometimes slopes are chosen to make sure that the notches match length of the armscye but beyond that I’d like to know if there are stylistic decisions that can be made using the slope of the notches.
Putting the center point of the sleeve cap toward the front increases the ease in the back, giving more room to move one’s arms forward, & less bunching at the front.
That’s the only one that I’m pretty sure of. Someone who is more dedicated to taking their concepts to garments will have to help with the others, (& hopefully not have to correct me about the center sleeve-cap notch.)
You mustn’t forget that the shoulder seam is normally about 1cm forwards at the shoulder tip than at the neck side. This is because of the natural forward position of the shoulders. The centre line of the sleeve is normally placed 1cm backwards from the shoulder tip position and is normally a crease line and is positioned at the position of where the shoulder tip would be if one didn’t bring the shoulder tip forwards on the shoulder line.
The only thing that the bicep measurement plays in the width of the sleeve is to make sure that the sleeve will accommodate the bicep. Other than that, the sleeve width is purely a design feature that is dependant on the type of fabric that you are using, what is the purpose of the garment (how much movement do you want to allow) and how tight or loose you’d like the sleeve to be. If you are using a stretch fabric, then yes, the bicep measurement will suffice as the width of the sleeve.
The notches are only to match the sleeve cap into the armhole and can be extra points added along the sleeve cap curve later, at the same distance from the armpit points as they are in the bodice armhole. They can also serve the purpose of indicating where the gathering of the sleeve cap should be, since it would be uncomfortable to have gathers in the sleeve under the arm, unless it’s a design feature.
The few gathers between the front and back notches also serve to ‘cup’ the sleeve head over the shoulder and the norm for woven fabrics (depending on thickness and stiffness) is to have the sleeve cap curve 2.5cm (1") longer than the combined front and back armhole measurement.
The actual slope of the curve has nothing to do with the notches, but rather depends on the height of the sleeve cap. If the sleeve cap is to be high, the width will be narrow, so the slope will be steep. If the sleeve cap is low, the width will be wide and the slope will be shallow. You will still be able to place the notches at the same distances on the curve as the armholes.
Shallow sleeve caps are normally used in shirts where the shoulder seam is extended over the shoulder tip, to allow for more movement, and the extra distance between the shoulder tip and the armhole edge is deducted from the height of the sleeve cap.
Okay I get that but then I would assume, considering that sleeve notch length is supposed to match their armscye counterpart (maybe this is an incorrect assumption), that patterns that use this off-centred centre would have longer armscyes on the back pattern than on the front. This because moving the centre point towards the front notch would shorten its length and lengthen the back sleeve notch which would need to be reflected in the armscyes of the patterns.
So that is to say that looking at it from the top, the center of the sleeve (if I were to draw a line there irrespective of whether it lined up with the highest point of the sleeve cap) would be in line with the shoulder seam at the point of the neck. But in many patterns the forward facing nature of the shoulders is taken into account meaning the the highest point of sleeve cap is actually pushed towards the front which means that the shoulder seam runs diagonally (looking at it from above). I unfortunately do not know what a crease line is in the context of seams but I think I understand this part of your answer.
Technically… it depends. The back side of a sleeve needs extra room for the shoulder blade, so the back half of the sleeve is usually shorter… which may be offset if the shoulder notch (top of the sleeve cap) is moved forward (green line) to meet the shoulder seam of the bodice. In the pic below the red line indicates how a 1 piece sleeve cap is adjusted on the backhalf:
BTW… for anyone interested… a sleeve pattern is more or less a truncated oblique cone. We had to draft this sort of thing waaay back in 7th grade drafting class.
Correct, from the armpit to the notch should be at the same distance on the sleeve as on the armhole.
No, the highest point of the sleeve cap should always be slightly behind the shoulder seam (of course, depending on what your patternmaking system says - always follow the instructions). An easy way ensure that the centre line of the sleeve is correctly positioned is to place a notch on the back armscye at 1cm below the shoulder tip. However, I’ve gotten away with matching the centre line of the sleeve to the shoulder seam when the cap needs to be gathered slightly.
When you iron a shirt, normally you’d fold the sleeve flat at the seam, iron the seamline area and then fold the sleeve at the seam and and iron the rest of the sleeve, creating a crease at the other side. This is the crease line and is also the centre line of your sleeve pattern.
I just thought of another way… Mark the length of the back armscye on the back sleeve cap and the front armscye on the front sleeve cap. Measure the distance on the 2 marks and divide the result by 2. Mark this point with a notch which will be the notch that matches up to the shoulder seam.
Correct… because arms generally tilt slightly forward, but of course there’s a lot of “it depends”. If it’s a lycra leotard you could be off an inch it aint going to matter at all, a polycotton T-shirt less so… and if it’s a men’s suit jacket 2 piece sleeve being off a 1/4 inch can really ruin the hang of the sleeve.
When I was learning patternmaking, I tried to use this method learnt from my scrapbooking days. It wasn’t very successful 