Quiltmaking 101 -- Sandwiching your quilt

After your quilt top is sewed together, it must be pressed very, very well.  It's almost impossible to do an adequate job of pressing a full quilt top on an ironing board, so find a table or even a floor where you can lay out a padded surface (an old mattress pad is great, or a wool blanket covered with a sheet).  Protect the table or floor if necessary with newspapers or another blanket underneath.

As with pressing individual blocks, start from the back and make sure all the seam allowances are pressed to one side or another -- no flips in between seams, which may be visible in the finished quilt and may hinder your quilting.

See if you can easily fix any flips by opening the seam, pressing in the right direction and sewing the seam closed again.  If you can't, because the bad place is too close to an intersection or is otherwise inaccessible, never mind; it's not the end of the world.

After everything is pointed in the right direction, turn the quilt right side up and press again, getting all the seams nice and flat.  Most important, make sure the top lies perfectly flat.  If it doesn't, figure out where you need to take in a seam or let one out.  If you have a bulge or valley in the top don't tell yourself  "it'll come out in the quilting" because it probably won't.  Fix it now!

If you follow traditional quilting directions, they will tell you to trim the quilt top to a perfect rectangle right now.  You can do this if you want to, but I tend to wait until after quilting to trim.  The fabric often gets a bit (or a lot) distorted because of all the stitching, and why take the time to trim it first only to realize that you have to trim it again?  So you'll notice that the edges of my quilt top in the photos are still kind of raggedy.

Now you can sandwich the top with its backing and batting. First lay out the backing, right side down, and press it well. 

Then put the batting over it, smoothing it out neatly.  (If the batting comes out of the package crumpled up, spritz it with some water and let it tumble in the dryer for a while to get rid of the folds.)

Put the quilt top over the backing and batting.  Leave yourself at least two inches of extra batting and backing beyond the edges of the quilt top; sometimes the layers shift in quilting and you don't want to run out of backing and have to cut off some of your precious piecing!  Press the three layers together.

Inspect the top carefully under the best light you can muster to catch any stray threads peeking up through the seams, or showing through a light-colored fabric, or any other glitches.  I sometimes bring a portable lamp over to the work surface to make sure the shadow of my head from the overhead light doesn't camouflage any bad spots.

Here's a stray thread peeking through the seam.  If you can't pull it free from the top, go to the back, find where it's coming from, and pull it to the back.

Here's the back view of a seam where light and dark colors abut and the seam allowances were pressed toward the light.  Note how the dark seam allowance was kept narrower than the light, to minimize the chances of see-through. Nevertheless, those stray threads raveling off the dark fabric will be visible from the top of the quilt.  Get a tiny scissors and clip them off.

When you're sure the quilt looks perfect, press it again.  Pressing helps meld the layers together and keep the quilt sandwich in place.  But pressing probably won't be enough to keep the three layers of the quilt sandwich properly aligned while you sew them together.

Quilting is a rough, tough process.  You have to manhandle your quilt and move it around a lot.  You have to force a relatively large volume of fabric under the relatively small harp of your sewing machine, by rolling, folding or wadding it to fit.  If you're not careful, the three layers can get out of whack, as one or more stretches a bit or warps on the diagonal or wraps farther around a fold then the other layers do.  As a result, you can get pleats or wrinkles on the top or bottom of the sandwich.

To prevent this shifting, quilters generally use some method of temporarily holding the layers together until they're permanently attached with the quilting stitches.  This can be done in three ways, each with its drawbacks:

You can baste the layers together with thread, in large stitches.  Drawbacks: Basting takes a lot of time, and it can be messy to remove the thread afterwards if you have sewed through it.

You can pin the layers together, either with safety pins or straight pins.  Drawbacks: Safety pins take longer to insert and remove, and that process is hard on your hands.  Straight pins can scratch and impale you while you're working.  With either type of pin you must remove each one just before you sew over it, lest you break your needle.  Quilters who like to pin sometimes do it in stages, pinning only a small area of the quilt to begin with; then after they've quilted that area, they lay the quilt flat, press it again and pin a new area.

You can glue the layers together, with a spray adhesive or a thin layer of heat-set glue (aka fusible web or fusible batting).  Drawbacks: The sprays can make a mess on your work surface and perhaps create a health hazard (you may want to wear a mask or respirator).  Any type of adhesive or fusible is expensive.