I did have a failure due to rubber bands folding the flat fabric into a hot dog bun. I should not have dyed the shirt and moved to another one but chalk that one up to learning. That swirl was the worst but "there is no bad tie dye." So I purchased some polypropelene purple twine. I can understand why one would not want to use cotton because of the dye. I think this will be ok since it does not seen to bleed in hot soapy water. I know that the color is added to the resin so I don't think it should bleed.
Anyone use this twine? Also is there an alternative to synthropal for the wash out? I have used two loads and already used 1/3 of the bottle. Maybe using too much. Thanks need to go to work.