Tuff Luff Problems: Is a 1205 Tuff Luff too small for J/30? New sail strips-out:

Boat had an old 1205 Tuff Luff. When I bought a new 163 (sailmaker "A"), put on a new 1205. But "A" put a #6 tape on sail without thinking about it. When it didn't fit, "A" removed the #6 and put on a #5, warned #5 is too small for J/30, and "all Annapolis J/30's use #6/1206." New sail (with #5) strips out of 1205 foil from the head down, even in light air. "A" said make sure we keep the sheets free/don't jerk/snap halyard during hoist, which pulls head out. Didn't help. Also, stripped sail caused groove damage to new foil, so I need to replace foil again. Older 155's (Sailmaker "B") worked fine in old and new foils. "A" said maybe the tape cloth was running thin, but measured only .006" smaller dia than "B"s sails. Consulted Sailmaker "C". "B" and "C" tell me all tapes come from 2 suppliers, and are the same. "B" and "C" think spending $1,000 to upsize sails/foil to 1206 is waste and the new 1205 sounds defective. Schaffer Marine says its a halyard angle problem (!?).

Headstay diameter is correct. Don't have a cap on top of the foil (per "A"s advice to KISS). Took effort to spread the foil and slide it on, but don't think I damaged it installing (Spring - warm day). Followed the directions.

I've heard other boats have this problem. Anyone solve it? Anyone seen a defective foil? Anyone sailing with a 1205?
hunter@i-stat.com

Thanks to those who called/emailed. Here’s what I’ve learned:
-You can ID luff tape size by color-coded threads in rope; #5-black/orange, #6-black
-Schaefer recommends using welded, not stitched luff tape.
-Sailmakers I spoke to use stitched-only. Easier to repair, time-proven.
-A poorly stitched luff tape could flatten and pull out. Try pinching the rope… does it flatten?
-Some think foil top-cap is important, others don’t.
-Schaefer and some sailmakers think #5 is right size for J/30, #6 overkill. I’ve carried #5 tape 155% in 35+ knots with no problem. Note, aluminum extrusions typically #6.
-Halyard angle to luff is critical. Parallel ideal. Reduce angle by cutting tape back further from the head (if the head/tape is close to the sheave), and/or flare the tape a bit (restitch) towards the top – done on BIG boats where sheave must be offset.
-Some sailmakers cut new sails long in the luff to compensate for shrinkage (as much as 8”!!!), this might bring the tape-top closer to sheave (different angle) than other sails.
-Haven’t heard from any Headfoil users...

Next season I’ll stick with #5 (Schaefer is sending me a replacement 1205 - thanks!). Will add top cap, match tape length to other sails, maybe flare a bit and stick with stitched. And since I have an old foil to play with, I’ll try making a plastic wedge to expand the foil for extracting a stripped sail quickly without causing major damage (or having to remove the bottom feeder) – hopefully wont be needed.