DN NA Class

I really like the chain-stitch/braided mainsheet, but it is a bit difficult to get the chain-stitched part through blocks smaller than 57mm.

To try and improve things, I am experimenting with a "composite" construction.
The chain-stitch is done using 3mm (~1/8") double-braid line instead of the usual 3/16". This line is not strong enough to handle the mainsheet loads itself, so a 3mm Dyneema single-braid line is used for the un-tapered part and woven through the center of the chain-stitch section to carry the sheet-tension.

This gives a slightly smaller diameter chain-stitched portion of the sheet (the primary goal). A secondary benefit is a smaller diameter line running through the blocks at the back of the boom.

Here's some more information: http://performancesailingproducts.com/HiTechChainstitchMainsheetPrototype.html

(http://performancesailingproducts.com/misc/IMG_5435_650.jpg) (http://performancesailingproducts.com/HiTechChainstitchMainsheetPrototype.html)

make a cone at front o f the knot, use some carpet foam or similar and wrap with sail thread and coat with some epoxy  to keep it together 

An update: a friend is using the sheet on my loaner DN and he seems to like it a lot.

I used it on my blokart® at Ivanpah in November and it worked really well.
It's a perfect fit for the blokart® because we use 57mm ratchets and ~29mm sheet blocks.
Currently the class limits mainsheet diameter to a minimum of 6mm. Hopefully they will eliminate that restriction.

I made one up using some type of 4 mm line I got from the local sail loft. It works great and I'm even using double ratchet blocks. It's also plenty strong enough.

Thanks for the report. I also made one with 4mm "Finish Line" (850 lbs. breaking). I haven't used it yet, but I think it may be a nice compromise between the typical 3/16" (4.8mm) and the "almost too small" 3mm+"core". I was a little worried about strength, but I'll give it a try soon.