No Traveler
Posted: Sat Sep 04, 2021 1:04 pmHelping a friend rig his 1970's DS 1. It came without a traveler and he is debating not installing one. He has a vang and mid boom mainsheet. Is this a good option?
That said, boom vang + midboom mainsheet doesn't sound too bad, except the boom vang shouldn't be a 3:1 in that case.
That would be a focused upgrade and one I can recommend, even if you later add a traveler.
Now, if he's sailed that boat for a number of seasons, already has a strong (12:1 or greater) vang and feel it's not working, then I would begin to look further.
There are a number of different traveler setups. A typical one would have a fixed triangle with a block at the apex to which the mainsheet is led before returning to the boom. This means that 2x the pull from your hand pulls at the end of the boom, and 1x pulls at the block in the center of the boom. Overall, this gives you the equivalent of a 5:1 center boom setup (because the lever arm at the end of the boom is twice as long).
4/5 of that pull go into the direction configured by the traveler, 1/5 goes in the direction to the center cockpit, so that contribution is so small we can approximately ignore it.
The block position at the apex of the traveler is not 100% fixed, because the triangle is not stiff. Your pull, when the boom is out, will be in the direction from end of boom to the quarter block opposite. When the boom is in far enough, both sides of the traveler will see some tension and the pull will be in the direction to that block.
Overall, the effect is that the mainsheet now pulls more sideways than without (and you use the vang to add leech tension, even upwind).
If you have an adjustable loop, you could move the apex position a bit, but I read that people don't bother. Mine allows fixed or floating (for downwind), but I regularly forget to change and wouldn't know whether it even makes a difference if the vang is engaged.
Hardware required would be two standup blocks at each quarter (a bit aft of the coaming on either side of the aft deck), a single block (swivel) and a line.
Here's a picture of the end of the boom with associated hardware and the top of my traveler. The block is fixed to a butterfly knot.
(click on images to enlarge)
The two ends of the traveler are tied together with a knot that leaves a loop that can be hooked over a hook in the center. I have mine attached to the back of the rear wooden coaming, where it is out of the way of the tiller. You may be able to guess its location from the second photo. If you wanted to use a pure fixed traveler, you could use eye straps instead of quarter blocks.
(If you want to copy my setup, you would use a sheet bend to tie the two ends together, but double one of the two ends before tying the knot. The result will be a short loop where otherwise a free end would stick out. If you pick the right end for the doubling, that loop can be loaded and the knot will still hold.)
One upgrade I strongly recommend is to change the block at the center boom to a ratchet block.
The final piece of conversion to a traveler is that you will need a different block / cleat on the centerboard, but if your friend has a fiddle block there, he could just no use the second sheave.
It's a moderately sized project, hence my suggestion at the beginning to make sure to upgrade the vang (something you might want to do anyway) and to sail using "vang sheeting", and see whether that works for you.