Sew Sarah smith

Dartless FBA for Knits – Do You Need One & What’s the Best Method?

Sew Sarah smith

Today’s mega topic for discussion is all about creating dartless Full Bust Adjustments for knit sewing patterns. There are loads of different methods out there; do you really need one and, if so, which works best? Are you sitting comfortably? Then we’ll begin!

Muse patterns

You may recall that recently I sewed up my first Jenna Cardigan. Whilst this is an easy pattern to sew it did throw up an interesting challenge, personally. The Jenna is designed for a B cup and has slight negative design ease in the bust. Being a D cup there was no getting away from the fact that I was going to need to create some extra room in there for my boobage!

With my first Jenna I did a ‘cheater FBA’; relying on the stretch of my fabric I merely attempted to create extra width by grading out a size at the side seam starting at the underarm and tapering back in at the waist. It was ‘kind of’ sufficient but I mostly found that I had excess fabric at the underarm and still needed extra snaps to get the button band to lay flush. Overall it left me feeling a bit ‘meh’.

So, I got out pen and notepad and set to work, researching the various methods for a creating a dartless FBA suitable for knits. This post covers what I found to be most, ahem, pert-inent 😉

// If you’re in a rush to get to the method I liked best, feel free to scroll to its full demonstration lower down! //

But, before I go any further into the various methods of knit FBA’s I discovered, I think when approaching your next knit project it’s worth asking yourself these three key questions:

Do you really need a FBA with this particular project? Don’t just assume you do! 

Basically the stretch quality of your knit fabric may be sufficient, if you’re working with a particularly s-t-r-e-t-c-h-y jersey for example. Some negative ease can also be  fine sometimes, say in a fitted Tee. However, in a front fastening cardigan it’s less likely to be enough. Check the finished measurements on your pattern; how much ease is built in? Is there enough to ‘cover your assets’? You’re never likely to need a FBA with the Linden Sweatshirt for example!

Importantly, if you are going to progress to doing a FBA it is crucial to assess the percentage stretch of your jersey as this will also influence how much, or how little, a FBA you need to do. With a woven FBA you would simply add half your required amount to your half bodice piece; however with a stretchy knit you may, for example, only need to add a quarter of that.

Are you shorter or taller than the pattern is drafted for?

If you are, it may be that your boobs won’t be accommodated properly irrespective of whether they’re technically in the right size garment or not, simply because the fullness of your chest won’t be in the same place the pattern assumes it will be! For example, if you’re shorter you may find you have lines, or a folded flap of fabric, radiating from the armscye of your finished garment. If so, you may need to do a Petite Bodice Adjustment, i.e shortening or folding your pattern piece horizontally across the upper chest and through the armscye to take out the excess length there.  You may still ALSO then need to do a FBA!

Are you planning to pattern match, say, stripe fabric?

Choose your FBA method wisely, not all are geared with this in mind (see below).

Ok, we’re getting closer to the fun stuff!

Basically, I discovered there are as many ways to do a FBA as there are to skin a cat.  I will say this though; no one method will ‘click’ for everyone. You have to discover the one that makes the most sense to you.

To this end I’ll merely list a few other methods in case the one I’m about to fully demonstrate below makes nada sense to you personally!

  1. Cheat – you know what they say, if in doubt…cheat. Just add extra width/grade out at the side seam. It works … to a degree.
  2. The ‘Pivot & Slide’ method advocated by Patterns for Pirates and Maria Denmark. Relatively quick and easy, this method essentially works by pivoting your pattern piece at the shoulder to re-grade it at the chest. In essence then, it just adds width in the bust area which is ok if you don’t need to do too big an adjustment perhaps. I personally wanted extra length at the front as well.
  3. The ‘Vertical only FBA’ see Communing with Fabric  which proposes doing the exact opposite of the Pivot & Slide method by simply adding length at the front by slashing and spreading at the chest.
  4. Alexandra Morgan’s two line FBA (You Tube) A lovely reader sent me this Vlog link (thank you Kathleen!) which is easy to follow. It illustrates two methods including one which simply eases the bust dart into the side seam, in pretty much the same way you’d ease a sleeve head into an armscye. This would only work sufficiently if your resultant dart legs were an inch or less wide. Side note of caution, bear in mind if you’re planning to sew with stripe fabric, again this is going to royally mess up your pattern matching!

NB. For an FBA larger than 1.5” it might be worth looking into Palmer-Pletsch’s Y Dart Method (illustrated here by the Curvy Sewing Collective) as a starting point. You will still need to rotate that dart out afterwards though.

But the one method, BY FAR, that made by brain sit up and take notice was the dartless method prescribed by Jennifer Lauren Handmade. Now, I admit, the first time I attempted to follow her diagrams I got a bit stuck at one key point – though this was probably 80D9C70D-E145-4D9C-BB41-49E65B61D435due to suffering the effects of severe sleep deprivation! When I went back to it I had a face-palm moment when *cue music* it finally clicked, the sun came over the horizon and all the little birdies started tweeting. You get the picture!

So, I thought I’d use my Jenna bodice piece to illustrate how I interpreted Lauren’s diagrams. Spoiler alert, the end result is TOTALLY BLOOMIN’ FANTASTIC AND ABSOLUTELY WORTH THE EFFORT. You get me?!

// The Demo Bit //

First off, I lay my pattern piece atop the ruler guides of my cutting board as it makes it easier to accurately slash and spread your pattern to the exact increments you’re after. You then start off by doing a standard FBA in exactly the same way you would for a woven garment…before rotating that dart out.

Unfortunately, determining and marking your apex is slightly trickier with a knit bodice pattern piece – if you haven’t made the garment before pop on a similar fitted jersey top and mark your apex with some masking tape. Whip it off again and then place your pattern piece over your top and transfer the marking.

Once you’ve marked your apex, draw in your usual cut lines – like this:


Cut through the red line from the hem through to the armscye; stop cutting a couple of millimetres before the armscye to create a moveable ‘hinge’. Cut the green line from the side seam, again stopping a couple of millimeters short of the apex point to create your second hinge.

Then spread your pattern piece at the apex point by your required amount. (I initially spread mine at 0.5”). This will automatically create the side bust dart you’ll remove later – you will also notice that your side length is now longer than your centre front length:

hiw to rotate out bust darts

Cut straight across along the blue line and lower that piece so it’s aligned:

FBA dartless knit sewing pattern

(I decided to go the whole hog and increase by an inch!)

Pop some more tracing paper under your cut pattern and stabilise it with pattern weights, tins of beans or whatever else you’ve got handy.

Align your ruler and draw in the line on your bottom paper, as a reference point for later, like so:

Dartless fba

Now tape your side bust dart back together (being careful NOT to stick it to the paper underneath!) – see how far your side piece now moves away from the reference line you drew in the previous step?

dart rotationBefore you taped your dart together, remember how it’s ‘hinge’ was at the apex point? Well, now we’ve taped the dart together we are again going to cut through it BUT this time cutting across in the opposite direction – from the apex to the side seam – again stopping a couple of millimetres shy of the side seam to create that all important hinge. What you’ve essentially done then in these last two steps is merely move the position of the hinge of the dart from one side to the other:

knit fba tutorial

Now this next step is where I initially got flummoxed when I first looked at this method *need sleep* but, simply, move the bottom left section back up to realign with the reference line you drew earlier. Notice how in order to do this, the piece above is overlapped? Bye bye dart!

moving out a bust dart

The last thing you will need to do is draw a curved line (like my dotted one above) to draw in your new hem line.

You have created extra width, extra length and rotated out your dart! (See note below regarding the potential need to retrace your waist curve).

At this point I drew around the whole thing to create my new bodice piece. Look how my finished piece compares with its original:

fill bust adjustment without dart

You may need to redraw your side seam – it is worth mentioning again that the bodice piece I’ve used here is a very cropped bodice which is finished with a long hem band and only then ends up sitting at the natural waist. I simply eased the excess width at the hem point into my original hem band piece to avoid baginess at the waist. If your bodice piece is of regular length you may want to consider redrawing your waist curve, i.e tapering back in at the side seam so that your waist measurement remains true.

dartless FBA knits

Clearly I’m no Oracle on the subject nor am I any kind of Pattern Drafting Ninja BUT this is what the finished cardigan looked like; see how the button bands meet equally along its entire length, with zilch gaping or straining at the bust? Result!

How to do a full Bust Adjustment with knit patterns

Until next time, I hope this was useful – let me know and please leave any other tips or suggestions you may have!

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Sewing with knits

The Jenna Cardigan by Muse – a workhorse of a pattern!

Sewing with knits

Hurray I’ve finally sewn up a Jenna Cardi! Although a relatively simple pattern, it wasn’t without issues; mainly around fit. Let’s just start by saying that Muse state this pattern is designed for an hourglass figure (hurray!), a height of 5.10″ (boo!) and a B cup (ah hum). I’m 5.3″ and a D cup…

I managed to resolve some of the issues – which were more than my standard adjustments –  at the paper stage, but I’m not done finessing yet. I’m considering this a wearable toile. I actually made it as part of this month’s Minerva Craft Blogger Network using their plain cotton jersey in the navy colourway – head on over to my post THERE for the full low down.

(If you’re looking for a simple tutorial on how to fit plastic snaps on your Jenna, I have one HERE).

Now, I do love this pattern, don’t get me wrong. I got the Jenna Cardigan Pattern Bundle (the basic pattern plus sleeve and neckline expansion packs) as it offers so much scope to mix ‘n’ match to create a whole array of different cardi’s. It’s because of its potential that I’m determined to nail the fit 100% – to make the pattern work for me as much as I worked for it, haha – because I see this being a pattern I reach for again and again…

…So now I’m set to research doing a ‘proper’ Full Bust Adjustment with knits (i.e without incorporating a dart) rather than the ‘cheat’ I utilised here (but, hey, whatever works, right?!) Expect to see me posting on that shortly! If you’ve any tips you want to share in the meantime, then please do!

Until next time, thanks for stopping by!




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