Most people call it Shape Flex - some Call it SF101 - we know what you are talking about!
After all it is one of our Top Sellers!
Shape-Flex SF101 is an all purpose woven fusible interfacing.
It provides crisp support for collars, cuffs, yokes, pockets, facings and other detail areas of a garment.
It can also add body and permanent stability when used as a backing for needlework and punch embroidery.
(When combining Shape Flex with other fusible interfacings, such as Fusible Fleece, first fuse the Shape Flex to the wrong side of the fabric before adding the Fusible Fleece.)
Savvy sewers know interfacing is the secret to professional-looking bags.
Interfacing may not be very exciting but it's absolutely essential for bag making as it provides body, structure, and durability to your chosen fabrics.
Without interfacing your bag will look limp and be flimsy.
The interfacing of a bag is as important as the foundations of a building.
It is fusible (the glue on the interfacing melts from the heat of your iron) on one side, so you would iron it with the fusible side (the fusible side feels rough/tacky) against the wrong side of your actual fabric.
Use Shape Flex first and then Thermolam Fleece-
The reason that the Pellon SF-101 gets fused to your actual fabric first is that it provides a nice, smooth base, since it is woven like your actual fabric probably is.
The Pellon Thermolam, which is a fleece fusible interfacing, is thicker, like actual fleece fabric, but it can look wrinkly (in my opinion), so that's why it comes after the Pellon SF-101, if you're using it for a bag.
We use Shape-Flex in all our Bags!
The Pellon SF-101 interfacing will not make your fabric stiff, but it will lend it more body.
For example, when ironed on to a quilting-weight/mid-weight cotton fabric, the fabric will now have the body of a decor-weight fabric.
It is great for areas of a project that take a little more wear, such as the pockets of a bag.
For patterns calling for Vilene interfacing this Pellon interfacing is similar