The bonding can also be affected by the amount of sizing or starch that is in the fabric when purchased. For the best results do pre- wash and do not starch.
Also heat and bond is particular on the temp used when bonding. If when the backing is pulled off prior to bonding to the next fabric the heat and bond is not a milky color , the temp on your iron is too high. Then when bonding do not use the cotton setting, using a lower poly setting. Heat and bond is a bit differnent in that it will be absorbed into the fabric if too hot and for too long.
Note :Heat and bond stains most batiks... permenantly both the light and the heavy. Ask me how I know this ... ARGGG.

Yes, make sure it's Lite...Heavy bleeds thru fabric's it's more for leather and heavy fabric. I use lite all the time with my applique's no problems.

more than likely you got the wrong Heat n bond!
For sewing/applique you need HNB LITE..the regular HNB says on the directions DO NOT SEW as it will gum up the needles.

I know, I sell a bolt of LITE a month easily!

I still prefer steam a seam myself, or misty fuse, but most like the HNB just fine!

Yes you need the Heat n Bond LITE.