Jib Luff- Wire or String

Can anyone share their opinions on this? If the luff is properly tensioned I can’t see any reason for using wire.

Hi Don

I think the issue arises at the extreme 1/2" or so at the head and tack of the sail. Wire is locally very stiff, and effectively reinforces these areas, particularly at higher apparent wind speeds. String allows these areas to distort or collapse.

Modern Footys that still have jibs mostly use bar forestays (usually carbon tube) so that the forestay stays reasonably straight even with a relatively light unstayed mast. Because thre is little or no tension in the forestay, the compressive load on the mast ios reduced and it can be made lighter still. Schemes have been suggested involving spreaders and sgrouds on bar forestays. I don’t know if anyone has actually tried one, but the idea is ceetainly wandering around.


I think the issue is ‘stretch’. You want the material that has the least stretch to resist the forestay sagging during gusts. The thickness of the line should not be a major issue as usually, it is buried in the jib luff.

The wire sizes that are used commonly in the IOM class have effectively zero stretch at the loads involved.

A forestay of a nonstretch line (if it exists) should work as well. So called low stretch line would not be as effective as wire.

In the IOM class be sure to check the rules for allowed materials.

Don, for your US1M, I don’t know of any materials restrictions.

Hi Don -

as noted above, you may want to drop a note to Earl Boebert - as he is using a carbon tube for a forestay in his RG-65 jib. Since it’s been on the water and sialing, he probably could give you a good idea of performance versus wire versus string.

Just a thought as I read the thread.