Creating custom texture - is there a correct resolution?

I have made several attempts to create custom textures torepresent things like ribbon wire, or wave springs.

However, every time I end up with a tiled image that has a solidedge on one of the sides. It is as though I were making the texturetoo small, and SW was adding extra pixels to force the image toconform to some internal standard. I've tried standard binaryincrements, to no avail. My trial-and-error method has failed tofigure it out.

Perhaps someone here can offer some insight?

Joe DunfeeSolidworksGeneral