When cloth diapering my youngest kids, I loved the concept of the all-in-one diaper, but I had the best leak resistance using diapers and covers that were completely separate from each other. And the covers that worked best were the old fashioned nylon pants like these from Dappi. I always kept some around, but I never loved the way they looked. When sewing for our grandbabies I decided to copy the design using PUL (a special fabric lined with polyurethane to make it waterproof) and fold-over elastic to create a cuter cover.
The two photos below show the basic pattern to cut the PUL. The pink pattern is a size small and the green is a medium. I usually make a pattern with newspaper first, and tweak it so that all the curves are smooth and the dimensions are right. I’ve laid my pieces out on a cutting board with a one-inch grid, so that should make it easier for you to figure out the general proportions. Remember when you’re cutting PUL that you CAN’T use pins, since it will puncture the waterproof layer.
Since babies vary tremendously in size and shape, I would encourage you to make just ONE cover at first, and try it on your particular baby so that you can fine-tune the fit before you make multiple covers the same size. One more hint: be SURE that you use polyester thread for the sewing, or else the covers will leak.
SIZE SMALL should fit a baby in the 8-12 pound range. You’ll also need to cut three pieces of fold-over elastic. Measure and cut carefully, because the better the elastic fits your particular baby, the less likely the cover is to leak.
~~Leg elastic= 6 to 7.5 inches.
~~Waist elastic= 11-12 inches.
If you are sewing for a baby who is very lean, or who is at the light end of the weight range, choose the shorter length. If your baby is very chubby or at the higher end of the weight range for this size, you’ll need the longer length. By all means, measure the high thigh area and low waist area of your baby if he’s handy! Keep in mind that sewing the elastic will stretch it slightly, making it a bit looser. Also remember to account for the overlap where you’ll sew the two ends of the elastic together.
SIZE MEDIUM (cutting measurements below) fits babies in the range of 12-18 pounds.
~~Leg elastic: 8-10 inches
~~Waist elastic: 13-15 inches
Start by sewing the side seams. I like to make a french seam – basically a double seam that encases the cut edges of the PUL leaving none of the outside fabric inside the cover. To do this, first sew the side seams with the waterproof layers touching each other, using a VERY narrow seam allowance. Then turn the cover inside out so that the right (pretty) sides of the fabric touch each other, and make another seam close to the other one. This will give you an encased seam that is less likely to leak. The photo below shows the inside of the encased side seam after the elastic has been attached to the leg and waist. All you see is the plastic layer, NOT the outer layer that could wick moisture from the inside to the outside.
After the side seams are sewn, it is time to do the waist elastic. Begin by sewing one end of the fold over waist elastic to the center back of the cover using a zig-zag stitch (preferably a stretchable zig-zag stitch if your machine has it). Just sew an inch or so, then pause and cut your thread. At this point I like to find the center front of the diaper cover and the half-way point of the elastic. Match up those two things, and take a few stitches to tack the center front of the cover to the centerpoint in the elastic, making sure that your fold over elastic is not twisted. (I don’t do this with pins because I want ALL the holes in my PUL to have thread in them.) Cut your thread and return to the center back of the cover, this time attaching the OTHER end of the fold-over elastic to the center back of the cover, again making sure that your elastic is not twisted.
Now that your fold over elastic is tacked down at the front and the back it is time to sew the entire waist seam, carefully positioning elastic as you go, trying to make your gathers as even as possible, and making sure that you’re sewing through both the top and bottom of the fold-over elastic AND the PUL that should be firmly sandwiched between those two outer layers. Sew the elastic while it is stretched out. Go slowly. This is tricky and your first cover will likely not look as good as you wish, but you’ll get the hang of it. In the photo below, you can probably see the tiny straight stitching where I tacked down the elastic at the center front. You can also see that the back edge is not exceedingly lovely, but it works fine anyway!
The leg elastic is done exactly the same way, beginning at the side seam and tacking down both ends and the halfway point before going back to sew around the whole leg edge. Here I’ve just set the elastic at the side seam and am getting ready to tack it down.
Below I’m sewing around the entire leg hole. My machine has a narrow arm that fits the leg elastic just right and actually helps stretch out the elastic smoothly as I sew. Just be sure that your zig-zag catches all thee layers: the top of the elastic, the bottom of the elastic and the PUL sandwiched between the folded-over elastic. PUL is slippery! Watch that it doesn’t shift as you sew– go really slowly. At the end of the seam I zigzag several times over the raw end of the elastic to make it lie down smoothly and not get frayed.
Once you’ve got your last bit of leg elastic sewn, your cover is done! GO HERE to see my cloth diaper tutorial! The original tutorial was written for a size small diaper, but per popular request I’ve added dimensions for a size medium as well.