PROCESS: Hemming Denim With a Union Special by Self Edge
Step 1 / The storied Union Special 43200G Chain Stitching Machine
The storied Union Special 43200G Chain Stitching Machine – The machine we use at Self Edge Los Angeles is from the 1970′s, the third and last generation of these sewing machines before they stopped production on them. These machines are known for their durability and the beautiful roping effect that they create on jean hems. They are becoming increasingly rare and fetch astronomical prices when they are put up for sale. Thread clippers, a rotary cutter, a ruler and other sewing tools help to complete the job.
Step 2 / The Cut
We start with a short consultation with each customer to determine what length to hem their jeans to. We measure out the correct length to cut off, mark it with tailor’s chalk, then use a rotary cutter and a ruler to make a clean, straight cut. The old adage “measure twice, cut once” strongly applies here.
STEP 3 / The Fold
Setting the initial 1/2″ fold is a crucial step in hemming a pair of jeans. Before teaching someone how to actually sew with the 43200G, I first have them practice making a 1/2″ fold several hundred times to develop muscle memory of the motion. The fold only needs to be set where the chain stitching begins, as the rest of the hem is rolled into the folder before it reaches the needle.
Step 4 / The Chain Stitch
Once the fold is set, the hem is tucked over the lip of the folder and held in place by the presser foot. The jean needs to be perfectly straight before starting to sew, so that the stitch will align when it comes back around. I was taught to use both feet on the pedal because it gives more control over the speed of the machine. As I’m sewing, I use my left hand to hold the leg of the jean taut, and my right hand to roll the hem as it feeds into the folder.
Step 5 / Lining Up the Finish
Most factory chain-stitched hems begin and end at the inseam to hide imperfections. We start and finish our chain-stitched hems at the selvedge outseam. I once asked one of our Japanese colleagues, with over a decade of experience in the denim industry, which was the correct starting point: “Outseam,” she said, “it shows that you have the skill to line up the stitching properly.”
Step 6 / Cleaning Up
The presser foot is lifted and the jean is pulled out of the machine. The excess threads are tied, then trimmed closely.
Step 7 / The finished product
The finished product is a clean chain stitch that aligns perfectly, making it difficult to distinguish where it starts and where it ends. The torque from the machine has created that highly sought after roping effect on the hem, which will become more and more evident as the jeans fade over time.
Mar 30, 2012