Quiltmaking 101 -- pressing curved seams

Just as sewing curved seams is a bit trickier than straight seams, pressing is also a bit more worrisome.  But with any kind of seam, you should get into the habit of pressing as a two-step process.  First press lightly from the back side, then turn the work over, check that the seam is good from the front, and only then press enthusiastically.  You want to find and fix any problems before you set them in with lots of pressure and moisture.



If you have sewed parallel freehand strips into a larger module, as in the block above, wait until you have them all stitched before you press anything.  Then sweep your iron across the entire set, pressing all the seams in the same direction in one swoop.  Fabric has a lot of forgiveness and will usually ease itself together nicely even if the edges aren't mathematically exact.  But it seems to lose a bit of flexibility every time it's pressed, so the first time is always the best.  If you have to return to a finished module and add more curved strips, spritz your existing seams well with water before you press in the new seams.

With more pronounced curves it is important to press the seam allowances toward the outside edge.  It's easier to get fabric to spread out under the iron than to get it to squeeze in and still stay flat.

When you press toward the outside, the dark fabric gets to keep its exact original shape; the seam allowance on the lighter fabric has to spread out a bit on the edge to lie flat.  Not a problem; fabric is usually willing to stretch.

When you press toward the inside, the dark fabric gets to keep its exact original shape and things look good from the back.  But underneath, the lighter fabric has to squeeze in to make the extra fabric fit.  

Sometimes this will work out just fine, but sometimes, especially with very tight curves, the underneath fabric can't squeeze in enough and instead it forms pleats.  A problem. 

No matter which way you press, you may come up with the occasional extreme situation where there seems to be just too much or too little fabric in the seam allowance.  If you have sewn garments in a past life, you may be tempted to get out your scissors and cut notches in the seam allowances to make them lie flat, just as you would do at the underarm of a set-in sleeve or at the curved edge of a patch pocket.  Please overcome that temptation!

Instead, try pressing first with plenty of moisture and see if you can encourage the fabric to stretch out and lie flat.  If it still resists, you can get your scissors, but instead of cutting slits in toward the seamline, cut around the edge parallel to the seam to reduce the width of the seam allowance and see if that works.  You can safely cut to within an eighth-inch of the seamline on a quilt that's intended for the wall; stick with a quarter-inch if you plan to use and wash the quilt.  If all else fails, it's better to make several slits that stop at least an eighth-inch shy of the seamline than to make a few that go all the way in.

One last word about pressing: we all were brought up to think that pressing occurs on the ironing board.  But quilters would be better off using the ironing board for fabric storage, as I do, and making another surface to actually iron on.  That's because it's important to have your entire piece lie flat as you press.

As soon as your piecing outgrows your ironing board, you're only able to get part of it to lie flat, and then you have to shift it around.  What frequently happens is that each segment is indeed flat, but the whole thing isn't -- just as you are able to press a garment in flat segments, even though the whole dress curves to fit your body.

So make yourself an ironing surface on your work table or a countertop or even on the floor.  You don't need fancy metallic ironing-board cloth; an old mattress pad, wool blanket or two thicknesses of a towel will do very nicely.

Quiltmaking 101 -- freehand and curved seams 3

If you want to sew S-curves or even more complicated curves, you probably need more precision than you can get from the just-sew-it approach described in the last blog post.  Instead you need to establish a seamline and cut seam allowances on either side.

You don't need to go all quilt-police-traditional and make templates to accomplish this, but you do need a way to make a copy of the curve that will become your seamline.  Why not do templates?  Because you would lose the spontaneity of the freehand curve and change the character of your improvisational composition, and also because exact templates are so fiddly and time-consuming.

Instead, here are two methods of making your curves fit together perfectly while keeping the freedom of the immediate free-cut line.  I call them semi-templates.  You don't need to cut templates to accomplish this, but you do need some way to "remember" your curve so you can add seam allowances as you cut.

The first method uses a template, but it's a free-cut template with a minimum of tedious fuss.  Start with some pattern material that's big enough to draw your entire curve, and a cutting mat big enough to let you do it with one swoop of the rotary cutter.  The pattern material can be freezer paper, newspaper, interfacing or tissue paper.  Lay it out on your cutting board.  Take your rotary cutter and slice a gorgeous curve through the pattern.  If you want, you can stop there, or you can cut more curves as long as they don't cross any of your previous cuts.

(In the photos below I've made four cuts, the start of a large "striped" panel that can keep on going as long as I want. After these pieces are sewed together, I'll have to retrieve the template paper with the curved edge of 5, then make more cuts for more pieces.)

Don’t separate the two halves of the cut yet – first take a pencil and mark across both pieces every six inches or so, and/or at critical points on the curve. And mark across both pieces at the exact top and bottom of the curve.

Pick up one piece of the pattern and lay it on your fabric, making sure you keep track of whether this is going to be the right-hand piece or the left-hand piece. Now visualize how wide you want your seam allowance to be, and free-hand cut that distance away from the template.

It doesn’t have to be a perfect quarter-inch – no need to fuss with rulers, just eyeball it. There’s enough give in the fabric that you will not have problems. Finally, pin the two pieces together at the marked points, and sew. The seam will press perfectly flat.






















Look at that beautiful curved seam!  Now put template #1 aside, get templates #2 and #3 and repeat the process for the next curve.

Place template #2 right up against the seam, and cut along its left edge, adding the seam allowance by eye.  In this photo template #3 is waiting, but I will actually cut it from a third piece of fabric, not maroon.

Note that I do not suggest you cut out all the pieces at once.  It's way too easy to lose your place and try to sew the wrong pieces together (ask me how I know).  Instead cut two pieces (one curve), sew and press, then move on.

With this method you can make curve after curve, as in this quilt of mine.  With some practice you can use this method to make winding-road seams with multiple changes of direction, as long as you mark and pin the seams carefully.

A variation of this method uses a marking wheel to draw your curved seamline directly onto the two layers of fabric, thus eliminating the template.  If you're not familiar with this tool, it's like a rotary cutter except its "blade" is dull, not sharp.

Instead of using the rotary cutter to make your curve, you use the marking wheel, which works exactly like the rotary cutter, with the same arm motion that gives you those nice, loose, artistic swoopy lines.

Layer two pieces of fabric where you want the curve to go, giving yourself plenty of fabric underneath (you don't want your curve to run off the edge of the bottom layer).  Limber up your arm and make a swoopy curve, pressing hard enough to crease both layers of fabric.

The creased lines don't show up all that well in the photos but they do in real life, at least long enough for you to cut and sew as needed.

Now separate the two layers, noting carefully which direction you need to extend for seam allowances. Switch to a rotary cutter and by eye, follow your creased curve a quarter-inch away.

As you did with the paper templates in the first method, put one or two marks across the seams and pin them so you match the curves before stitching.  The more complicated the curve, the more places you should mark and pin.

In the next post I'm going to tell you to press your seam allowances toward the outside of a curve.  That's great with a C-curve, but how about an S-curve?  The "outside" may be toward the left as you start, but then the curve changes direction and "outside" is toward the right.  I can't give you a hard-and-fast rule for these situations.  If one leg of the curve is more gentle than the other, press that one toward the "inside" so it will become the "outside" when the going gets tough.  If all else fails, flip the direction of the seam where the curve changes direction.  Use your best judgment, and plenty of moisture and elbow grease at the ironing board.

Quiltmaking 101 -- freehand and curved seams 2

If you have chosen to cut your quilt pieces freehand instead of using a ruler, or if you are deliberately using curved seams, you face a construction issue: how to make the finished seams lie perfectly flat.  If the curves are gentle -- think the profile of a watermelon -- and if they curve in the same direction, you can usually just sew one to the other and they will be fine.

This approach works as a new construction method if you layer two pieces of fabric on top of one another, then cut a gentle curve through both layers.  Swap the pieces and stitch them together.

The piece above was made with three cuts, not one, and of course it yielded a mirror image piece with the same curves but the opposite color arrangement.  Note that the middle seam ended up wonky, with the black quite a bit longer than the orange, even though they were presumably the same length to start with.  This is not a failure of sewing skill; it's an unavoidable and unpredictable result of the process of sewing two bias edges together.

When this happens to you, and it will, don't feel guilty, don't try to rip the seam and redo it, just trim off the edge.

The just-sew-it approach also works with random pieces that you may find in your stash and want to sew together.  As long as the curves have approximately the same radius, and point in the same direction, you'll probably be fine.  But if they point in opposite directions, or are too radically different in profile, you'll end up with bulges or clots.  Plan ahead, and don't do that.

These pieces will most likely go together beautifully.  

These pieces won't.

With gentle curves the actual sewing will be very much like holding straight edges together -- no big deal.  But when you sew more pronounced curves -- as the watermelon profile becomes more like a cantaloupe or a grapefruit -- it's harder to maintain the proper seam allowance because the two edges are so different in profile: one a distinct hill and the other a valley.  It will be easier if you hold the "valley" curve on top and the "hill" on the bottom, even though that makes a lousy mnemonic.

Establish the seam allowance at one end of the seam and put your needle down through both layers.  If possible, set your machine so it automatically stops with the needle down, to make sure the pieces don't slip out of alignment when you stop to reposition the fabrics.  Carefully align the edges of the two layers and stitch for maybe a half inch.  Stop needle down, and reposition the fabric.

Make sure you can see the edge of the under layer, because it curves away from the needle and if you're not careful you can sew right off its edge.  If you stitch with a hint of pink peeking out from under the yellow, you'll be fine.  Yes, this is slow going, but this is how you get a perfect seam.

The top layer will form ruffles behind the needle as you stitch around the curve.  Don't pull tight on the top layer as you hold it in position; if anything, ease just a bit of extra fabric into the curve as you sew.

After you get to the end of the seam, flip it over and check whether you have inadvertently sewed any pleats into the bottom layer of fabric that you couldn't see.  If you have, get your seam ripper and open the seam for a quarter inch on each side of the pleat.  This time sew with the "hill" side up so you can watch carefully as you ease the fabric under the needle and get it smooth this time.  It's important to fix any glitches before you press, while the fabric is at its most flexible.

Sometimes you'll sew curved edges together, press the seam, and it looks as though everything is perfect.  But when you flip back to the right side, you'll notice that the two edges didn't match perfectly. When you turn that curved seam over, run your fingernail along it from the downhill side to find any hidden pleats.

If you find one, don't worry -- it's very easily fixed.  Turn it back to the wrong side and notice that the iron has creased the fabric at exactly the right place to give you your perfect seamline.  Restitch the seam along the crease mark and the curve will look exactly as it did before, except the new stitching will have closed the pleat.

Looks great from the front, but....

....there's a huge gap at the end of the seam between black and  yellow.

Go back and stitch exactly on the crease line. 

You will note that all the curves in this post go in one direction only -- no S-curves or multiple-winding roads.  If you want to sew these more complex curves, you'll need a more precise method to make them lie perfectly flat; stay tuned for the next tutorial.

And then there will be more about pressing curved seams in a further installment of Quiltmaking 101.  Wait and read that before you take your seam to the ironing board.

Quiltmaking 101 -- freehand and curved seams 1

The rotary cutter is a blessing for anybody wanting to make straight edges, a huge improvement over tracing around a template with a pencil and then cutting along the line with a scissors.  Rotary cutters, paired with rulers, make perfectly straight edges with very little work.

Although traditional quiltmakers have always worked with ruler-straight edges and seams in most block construction and when sewing blocks together, contemporary artists often prefer the looser look of freehand cutting.  You still use the rotary cutter and mat, but instead of lining your blade up against a ruler you cut without a guide.  Even when an edge/seam looks almost straight, you can see the artist's hand in a freehand line where you don't get that vibe from a ruler-cut line.

On the left, freehand straight lines; on the right, ruler-cut:

Can you see the difference?  It's subtle, especially if you're only looking at one block, but gives a different character to the finished quilt.

The problem with freehand cutting is friction.  In an ideal world, your fabric wouldn't be the least bit slippery and your rotary cutter would be so sharp and roll so smoothly that it would cut a clean edge without pulling at all on the fabric.  You would finish your cut with the two pieces of fabric exactly in their original places, so perfectly aligned that you would barely be able to see that they were cut at all.  In the real world, the blade catches just a bit and pushes or drags the fabric along with it a hair as it rolls along; you'll often see a bubble of fabric moving ahead of the blade as it cuts.  This is especially true if you are cutting two layers of fabric at the same time.

To prevent this, and to make sure that the cut goes exactly where you want it to, it's helpful to hold the fabric in place as you cut.  For short cuts, you just hold it down with your fingers (being careful, of course, not to cut yourself).  For longer cuts, anything over a foot, I like to hold the fabric in place with the plastic ruler, but keep the cutting line at least a quarter-inch away from the edge of the ruler.  That way you get the best of both worlds: the freedom of the freehand cut, where you can wobble or curve your line if you want, plus the ease of cutting fabric that stays where it's supposed to.

When you're joining almost-straight strips and blocks, you can pretty much just put them together and sew a straight seam; the fabric will have enough give to press flat. But as the seams get longer, or as you're joining long rows of blocks, or if your freehand cut had a bit of curve to it, you have to be a little more careful.  If you're not, you can end up with a hill or a valley or both, and even the most diligent pressing won't make them disappear.

Stay tuned for tips on how to sew not-straight pieces of fabric together and still have them come out perfectly flat.

Quiltmaking 101 -- batting cleanup

Several years ago I started a series of blog posts that I call Quiltmaking 101 -- tutorials on all the basics of machine-pieced quilts.  Early installments deal with how to use the rotary cutter, how to stitch seams and how to press.  Moving along through the production process, you can learn how to efficiently sew block-to-block quilts together, how to put the quilt sandwich together, and how to quilt it.  Finally, you can learn how to finish the quilt, with bindings or facings, and how to put a sleeve on for hanging.

I think that somebody who never saw a quilt before could probably learn 99 percent of what she needed to make one by following this series of tutorials.  If you want to read them, they're all right here.

But I realized recently, as I went back to check out one of the posts, that I had left some gaps in the instruction.  Most embarrassing, I realize that I never explicitly discussed freehand cutting -- the heart of improvisational quilting -- and how to sew together a quilt with curvy pieces.  So I am putting together a series of posts on piecing curves.  By that I mean both gently curved seams like these:

and more severe curves like these:

I'll be posting these new tutorials in the next couple of weeks.  Meanwhile, I invite you to look at the Quiltmaking 101 link above and tell me if there are other basic skills that you'd like to see additional tutorials on.

Quiltmaking 101 -- facing your quilt with curved edges

Facing the standard quilt (one with straight edges and square corners) is pretty easy, but recently a friend asked me how she should face a quilt with curvy edges.  Basically you use the same techniques, but with a few tweaks.  Start by reviewing the directions for facing a standard quilt. 

The first step is to trim your quilt to the appropriate smooth curvy edge.  Remember that you'll need an extra half-inch seam allowance to turn under.

Now contemplate your quilt and note just how curvy those edges are.  Lay your quilt out on a cutting mat (or for big quilts, on a floor with straight boards or linoleum pattern) so the curvy edge pretty much follows a straight line and the highest peak of the curved edge falls right at the line.  Now lay a ruler or straight edge on top of the quilt, parallel to the line on your mat or floor, to find approximately where the edge of your facing is going to fall.  Allow two inches of facing below the deepest valley.

This little quilt is aligned at the zero inch mark on the cutting mat.  We'll need to cut the facing 3 1/2 inches wide.

This side has a gentler curve, so the facing only has to be 3 inches wide.

You'll need to remember where to place the facing when it's time to sew.  Before you lift your ruler, put some pins along the edge, every six or eight inches.

Do the same thing for the other sides of the quilt: establish your straight line, pin-mark the edge, and cut facings to the correct width.  Depending on the curves, the facings may be different widths, so make sure you keep track of which facing goes on which side.

Lay the quilt out flat on your work table, good side up.  Place the facing on top of the quilt, right side of the facing against the right side of the quilt.  Line up the inner edge of the facing with your pin marks, making sure that you have the facing smooth and taut along the length of the edge.  The outer edge of the facing should just touch the tops of the curves on the edge of the quilt.

Pin the facing to the quilt, every eight inches or so.   But how do I know where to put the pins, you're saying!  I can't see the edge of the quilt!  That's right, but you can feel it, so you can tell that you've pinned through the facing and the quilt.  Now remove the original pins that were marking the edge of the facing; they've done their job and you want them out of the way.

If you'll recall the standard facing directions that you reviewed earlier, you would hold the facing on top of the quilt as you stitch.  But as you just noticed, you can't see the edge of the quilt, so that would be difficult.  Feeling the edge was accurate enough for pinning, but it isn't accurate enough for sewing.  So turn the quilt over, with the facing on the bottom and the back of the quilt up.

If you have a fussy sewing machine that doesn't like to sew over pins, or if it makes you nervous to sew with pins on the bottom of your work instead of visible on top, you can carefully put new pins on top, then take out the pins on the bottom.  

Now you can sew the entire length of this side of the quilt, leaving a half-inch seam allowance.  Don't use too small a stitch length, because you're going to have to take out some stitches at the corners for the next step and you don't want to shred your fabric.

To sew the second side, pin as you did the first, except when you get to the corner.  As explained in the directions for standard facing, you need to finger-press the turnback for the facing and hold it in place.

Then place the new facing on top, pin and sew.

When you get back to the first corner, you'll need to rip back the stitching on the first facing strip so you can place the fourth strip underneath.  (Just hold it in the same orientation as this photo to make sure you're doing the right thing.)  And you'll cut the first strip off about a half inch past the edge of the fourth strip.

Now trim the facings to a half-inch along the curves.  As explained in the directions for standard facing, rip out the stitches at each corner, fold back the backing and quilt top and clip off a little triangle of the bulky batting and backing.

Restitch the corner.  It looks like this on the other side.

Turn the corner inside out and fold back the facings, feeling and pressing with your thumb and fingers to get everything lying flat. Working from the wrong side of the quilt, turn the facings a bit farther back than the actual fold line so they will not be visible from the front. Pin the facings every one or two inches as you go.

Because of the curves, you'll  have to work those edges more than if they were straight.  Pinch, fold, massage the various layers into submission.  You may find a couple of places where you need to clip the inner layers to let them spread out around a valley, or to notch them to let them cram into a hill.  But DO NOT CUT all the way to the seam, just halfway. You dare not risk that a clip might migrate past the seam and show on the top of your quilt!  And if you need to cut more than one layer, stagger the clips or notches so they're not directly on top of one another.

DO NOT CUT anything unless you first try to fingerpress it into place.  Fabric has a lot of give to it, and with gently curving edges, you may be surprised that you can ease things into place without clipping or notching.  On the other hand, make sure to inspect the right side of your quilt carefully before you proceed.  A place may have felt OK as you were pinning but have an ugly pucker when you look at it closely.  (Like right below that white pin.)

I removed the pins and clipped the inner layers in a couple of places, then repinned.  Much nicer now!

As you can see in the photo above, the facing will have a straight edge toward the center of the quilt, but will vary in width with your curves.  You may want to keep the outer pins in until after you have stitched the facing down.  You may also want to press or block the quilt to set the folded edge more securely.

Quiltmaking 101 -- binding your quilt 3 -- folding and stitching the binding

Take your quilt to an ironing surface and lay it face up.  Press the binding out toward the edges of the quilt, admiring how neatly the corners have mitered.  You can't press the binding out beyond the corner, because it isn't long enough to lie flat, so just do the part over the quilt with the tip of your iron.  Or you can just finger-press the binding outward.

Now flip the quilt over face down onto a work surface so you can work along a top edge.  Start in the middle of a side -- we'll do the easy part first before tackling the tricky corners.  Pull the binding over the edge and toward you, pulling as taut as you can.  Fold the binding in two, with the cut edge right up against the cut edge of the quilt, then fold the edge down to just barely cover the stitching line.  If for some reason it isn't wide enough to cover the stitching line, you can ease the fold out a bit; at this point it's more important to cover the stitching line than to extend the binding all the way to the edge on the inside.

Pin the binding in place, every two or three inches.  Work out to the right and left, stopping about three inches from the corners.

Place one corner of the quilt on your work surface, facing top right.  You're confronting a section of binding that kind of stands upright as it turns the corner, because it's not long enough to lie flat.  That's good, because you now have to fold all that extra fabric in at the corner, and the less you have to deal with, the less bulk you'll have at the corner.

On either side of the corner you have already established a final folded width for the binding, and you are now going to finger-press that fold line all the way around the corner.

Once it's creased inward, pin the right-hand side of the binding up toward the corner.  When you get to the corner, take a sturdy needle and use it to push the rest of the binding all the way up to the top edge of the quilt.  Simultaneously, make sure you are pulling the binding as taut as you can around the right-hand edge of the quilt.  Pin the binding in place as close as you can to the edge.

Now fold the top part of the binding down over the needle.  Because you have creased the foldline into the binding, it should stay in place pretty well.  Pin that down quite close to the corner.

Check the corner of the quilt, front and back.

On the front, the diagonal miter should come out of the corner of the seam and go exactly to the corner of the quilt.  The binding should fold over to the back and lie flat, with no bubble at the corner.  If there's a bubble, unpin the bindings and pull the right-hand edge even tauter around the cut edge of the quilt, while urging the top binding to fold down flat.

After you have all four corners mitered and pinned, you can stitch the binding to the quilt.  If you sew by hand, work from the back and stitch through only the backing layer so your stitches aren't visible from the top of the quilt.  If you sew by machine, it's hard to keep a straight stitch exactly on the edge of the binding, both front and back.  But a zigzag stitch camouflages any slight differences in binding width and looks great from both sides.  I like to stitch from the front side of the quilt, centering the zigzag just a bit inside the seamline (closer toward the edge of the quilt).

Sewing the binding with a zigzag stitch -- front of the quilt

Sewing the binding with a zigzag stitch -- back of the quilt

Quiltmaking 101 -- binding your quilt 2 -- sewing the binding

Time to sew the binding to the quilt.  I use a walking foot, because the three layers of the quilt can shift under the pressure of a regular foot, even after they have been quilted together.

Place one end of the binding strip about halfway down one of the edges of the quilt, aligning it with the cut edge, but don't start sewing right at the end.  Instead, leave about six inches of strip hanging loose before you start sewing.  Sew at your predetermined seam allowance till you get almost to the corner.

Stop your stitching exactly one seam allowance from the corner.  Make a back stitch or two to hold the strip in place.

Cut the threads and take the quilt out from the machine.  Rotate it 90 degrees counterclockwise and place it on your work table with the edge you've sewed at the top, and the new edge straight ahead of you.

My finger hides the edge that has just been stitched.

Fold the binding strip up and away from you.  The right edge of the binding strip aligns with the cut edge of the quilt (that's why you place it right ahead of your nose, so you can eyeball the straight line).  Pull the strip taut so the diagonal fold line comes through the end of your stitching.  Press the diagonal fold with your thumbnail to help it keep its place.

Now fold the binding strip back on itself, exactly at the cut edge.  Align the fold with the top edge of the quilt, and align the edge of the binding with the side edge of the quilt.  The diagonal fold should end exactly at the corner of the quilt.  Put a pin through all layers, about a half-inch from the edge.

Back to the sewing machine; start sewing at the edge of the quilt and stitch the binding strip almost all the way to the next corner.  Repeat the mitered corner.  Twice more, and you'll get back to the side of the quilt that you started on.  Stop sewing about eight inches before you get to your starting point, cut the threads and take the quilt out from the machine.

You have about six inches of binding hanging loose from the beginning, plus whatever is left of the strip you have been sewing.  You now have to join those two ends at exactly the right place so the finished binding won't be either too long or too short.  You are going to sew those two ends together, which means you'll need a quarter-inch seam allowance on each end, which means your strip has to be a half-inch longer than the finished length.  So let's build in that half-inch right now.

Fold back one of the strips (doesn't matter which one) right at the end of the stitched part.  Put a quarter-inch tuck in it, and pin that in place.  There's your extra half-inch, ready for when you need it.

Arrange the two loose ends of the binding smoothly on top of one another and cut through both strips with one snip of the scissors.  (Don't cut the quilt top or any other fabric that might have sneaked in between the blades.)  Hold the scissors at an angle, or perpendicular, whichever way you did the other seams on the binding.

Here the two ends meet exactly at the snip line.  When you remove that pin tuck, you'll have the extra half-inch seam allowance to sew the two ends together.

But this seam is going to be tricky, because you need some extra room to maneuver, and the big quilt wants to spring loose and lie flat.  So make it give you the room you need -- pin a two- or three-inch fold into the part of the quilt that hasn't yet gotten its binding.

Notice the blue pin holding the big fold into the quilt, to give you slack to work with.

Pin the ends of the binding together, just as you joined the other binding strips.  Manhandle the quilt into place so you can sew the seam.  Make sure the weight of the quilt is well supported so it doesn't pull away or spring loose as you stitch.

When you take the quilt out from the machine, unpin the big fold, and lay it flat, the binding should be exactly as long as you need it.  In fact, it should be just a hair shorter, because the fabric will stretch a bit and the seam will lie perfectly flat.

If the binding is even a bit too long, DO NOT plan to ease it in as you stitch, because you'll get an ugly bubble and bulge.  Instead, go back to the machine and restitch the seam just a hair inside the previous stitching line.  No need to take out the first seam, just sew alongside it.

With your joined binding lying perfectly flat on the edge of the quilt, go back to the machine and complete the seam, overlapping for a half-inch or so on top of the previous stitching.

Next week:  folding the binding and stitching it in place.