If you are serious about dressmaking, it may be a good side at stay away from fusible hem tape and choose more long-term, machine applied techniques. While fusible hem tape is not a method used too often in the garment construction process, it can be  quite effective and convenient when sewing single use garments (such as Halloween costumes) or reinforcing fabric folds and hemlines when stitching is not an option. The projects lifespan and care should be considered when deciding whether to use a fusible hemming technique. 

If you choose to finish your garment's hem with a fusible  hem tape, consider how the hem tape will effect the hemline's final drape and movement. Once fused, the hem tape melts to permanently bond the fabric layers. The melted adhesive can often add some stiffness to the hem layers thus it works best with medium to heavier, already structured, fabrics. 

It is also important to consider whether the hem tape will successfully bond to the fabric surface. Some heavily textured and decorative fabrics do not respond well to the hem tape application. The adhesive may not bond well, coming apart easily when pulled. In this case, it is best to use either a hand applied or machine stitch to finish the garment's hem. 

You should not use fusible hem tape with sheer, see-thru fabrics like chiffon, organza and netting (to name just a few). The hem tape will show through the garment's hem resulting in a less-then-professional finish. It is also important to keep in mind that sheer fabrics are often lighter weight, featuring a more fluid drape. Hem tape tends to stiffen the folded fabric edge which will affect the finished garment's draping capabilities, 

You should never use bonding hem tape with fabrics that are susceptible to bleed-through. While you may not know how a certain fabric will respond to the hem tape adhesive just by looking at it, it is smart to test a scrap piece of your fabric to check if any bleed-through occurs. Fabrics that are most vulnerable to bleed through are those that have a satin finish like the one shown in the image above. 

It is important to consider that hem tape is a permanent finish. If you've applied it incorrectly the first time, the bonded fabric layers will  become stained with adhesive which is very difficult to remove. For taht reason, check twice before bonding the finished hemline and always test a scrap piece of your fabric prior to applying the hem tape to the final garment.