[Toxopholist]

Hi
Why not have a go at making your own? A single loop Flemish twist string only takes around 20 minutes and all you need is a serving jig. No string making jig is required.

Are you sure there's anything wrong with your current string? It's normal for them to stretch when first used as the twists bed in. This sack should then be taken up at the knotted end. Sometimes it is just the knot that slips a litlle also.