Rig Tuning - Dufour 34 Performance

[amusgrave]

Hi .. I have the Brian Toss video on rig tuning which is excellent .. but looking for some more info on doing a rig tune on a Dufour 34P w/ fractional rig w/swept back spreaders.

http://www.dufour-yachts.com/dufour....os_voiliers-34

I can't seem to get even the most basic info for tensioning the rig from Dufour or Sparcraft. (It has a Sparcraft Ocean series rig).

Most riggers seem to do this by feel .. but to the uninitiated who don't have the touch yet, this isn't much help.

Do you have any suggestions on tensioning the outer (5/16") shrouds and inner lower and inner uppers (9/32"). Are there any specifications on how much tension is optimal. I have a Loos Professional PT-3. Any thoughts would be appreciated.

[Brion Toss]

Hello,
The sailplan shows a double spreader fractional rig. It appears to be discontinuous, branching at the lower spreaders. If I understand your terminology, the verticals under the spreaders (V1's) are 5/16" and the other shroud bits all 9/32". Is this right? Is the forestay also 5/16"? Are there check stays and/or running backstays? Is there an adjustable backstay?
So far all I can tell you is that the if you have a discontinuous rig, the V1"s are likely going to be set at around 10 to 12%, the D2's (from lower spreaders to the mast at the upper spreaders) at barely 10%, perhaps less and the V2's (to masthead) and D1's (lower shrouds) negotiable. Check in about configuration, and we'll go from there.
Fair leads,
Brion Toss

[amusgrave]

Thanks for the info .. I'll try to explain further.

The rig is indeed discontinuous, branching at the lower spreaders.

The V1's (5/16") run from the deck chainplate (where there is a turnbuckle) to the lower spreader discontinuous tip. These currently have quite a bit of tension on them. The V2's (5/16") run from the lower spreader discontinous tip through the upper spreader continuous tip to the mast head. There's no adjustment (ie. turnbuckle) on the V2's.

The D1's run from the deck chainplate (where there is a turnbuckle) to the spreader bracket for the lower spreader. The D2's run from the discontinuous spreader tip on the lower spreader (where there is a turnbuckle) to the upper spreader bracket. The D1s and D2s are 9/32"single strand stainless steel Dyform cable.

The forestay, backstay and outer verticals are all 5/16". The D1's and D2's are 9/32"

The backstay splits with a 32:1 purchase and is adjustable. There is no checkstay.

Further info on the rig and spreader tips specifically can be found here:
http://www.charlestonspar.com/us/tec...ders_ocean.pdf

I've posted a couple of pictures of the rig including spreader tips here: http://sailorman-familyblog.blogspot.com/

[amusgrave]

Brian .. Can you check in on this .. I posted some additional info .. thx.

[amusgrave]

Brian .. as per your note ... here's the additional info on the configuration on my Dufour 34 that I posted earlier ... Let me know any thoughts on tensioning the rig and any specifications on how much tension is optimal on the V1s, D1s and D2s.
__________________________________________________ ______

The rig is indeed discontinuous, branching at the lower spreaders.

The V1's (5/16") run from the deck chainplate (where there is a turnbuckle) to the lower spreader discontinuous tip. These currently have quite a bit of tension on them. The V2's (5/16") run from the lower spreader discontinous tip through the upper spreader continuous tip to the mast head. There's no adjustment (ie. turnbuckle) on the V2's.

The D1's run from the deck chainplate (where there is a turnbuckle) to the spreader bracket for the lower spreader. The D2's run from the discontinuous spreader tip on the lower spreader (where there is a turnbuckle) to the upper spreader bracket. The D1s and D2s are 9/32"single strand stainless steel Dyform cable.

The forestay, backstay and outer verticals are all 5/16". The D1's and D2's are 9/32"

The backstay splits with a 32:1 purchase and is adjustable. There is no checkstay.

Further info on the rig and spreader tips specifically can be found here:
http://www.charlestonspar.com/us/tec...ders_ocean.pdf

I've posted a couple of pictures of the rig including spreader tips here: http://sailorman-familyblog.blogspot.com/