@Sudsy, I prefer the choices at JoAnn's Fabrics to the selection at Hobby Lobby or Walmart. I use the #40 cotton drill from JoAnn's and have found a great 100% canvas from JoAnn's.
Your patches are telling you that the material is too thin, the crown is too sharp and the lands have burrs. You will be well served by smoothing out the crown, taking some of the sharp edges off the lands and getting a thicker patch.
Your patches are telling you that the material is too thin, the crown is too sharp and the lands have burrs. You will be well served by smoothing out the crown, taking some of the sharp edges off the lands and getting a thicker patch.