When a coat comes down to me to put together, ready for a forward fitting, I need to baste the cloth, canvas and other parts together as well as sew other seams permanently. On the front section of a coat you can see in the picture, the front edge (the leading edge, where the buttons will be) has been sewn together using a machine and the pockets put in, as well as the cloth being basted to the canvas to keep it flat.
The first and most important step is that basting to the canvas, which is done by the three rows of white stitching you can see here. I need to make sure that these two elements are perfectly flat and perfectly aligned, that there is no excess in the cloth anywhere. When the coat is complete, these stitches will be removed and the two materials will be able to move freely against each other, to adapt to the wearer’s chest. But at the fitting stage you want to remove any possible movement, to make sure the fitting is precise.
The hip and out-breast pockets are sewn in first, before these two materials are basted together. The pockets are sewn in permanently. A further row of temporary stitching is then run down the front edge, just a little way in, to keep it in place and rolling ever-so slightly inwards. That means you don’t see the seam from the inside. The same thing is achieved by a row of basting stitches on the inside of the coat, where the facing meets the lining.
Once the coat is fitted, adjusted and ready to be finished, these basting stitches will be taken out. The canvas will be secured at the front edge, around the armhole and at the edges of the pockets. But otherwise it will be able to move and mold to the customer.