dyform

[mld]

Our 10 year old Beneteau 45f5 was on the hard in Grenada during Hurricane Ivan. The boat ended up on her side but with the rig intact. To put her upright they had to cut the rig off. In addition to fixing the boat we have a problem with the rig - it is no longer on the boat and many of the turnbuckles are frozen on. The rigger in Grenada suggests we rerig with dyform. We know nothing about this stuff, we liked our rod rigging, we are floundering! Are we crazy to spend time trying to inspect our existing rig ( got to get those turnbuckles off! )? Is dyform a good replacement for our rod? We do not race but do like performance sailing - we raced a 470 prior to going cruising. Any thoughts would be most appreciated.

[Brion Toss]

Hello,
Dyform will give you nearly the performance of rod, with a good deal less bother in your current situation, as it ships fairly compactly, and the terminals can be assembled on site. And I'm not sure that your boat would notice the difference. The hangup in a conversion is usually at the ends: do you have conventional tangs? Some rod tangs are incompatible with Dyform terminals, so you might have to install new ones.
The spreader tips can also be a problem: is this discontinuous rigging?
And what do you mean when you say that the turnbuckles are "frozen on"? If they are galled, they are not worth salvaging. And if they are Navtec turnbuckles, you are better off getting conventional ones for your Dyform.
If you use Dyform, make sure that the wedges for the Sta-Lok or similar fittings are specifically for this construction. Do NOT use Dyform for your backstay if it has a hydraulic adjuster on it.
Fair leads,
Brion Toss

[Bob Pingel]

Why don't you want to use dyform with a hydraulic adjuster?

Bob

[mld]

Thank you Brion for your help,
Our rigging is Ageca and yes, it is discountiuous. We have been told that they can not use the spreader tips with the new rigging. As for my meaning of "frozen on", we have gotten a few of the turnbuckles off with much work and it seems to be a lot of gunk such as salt, Afican dust etc. that cleans out once you get the turnbuckles off but many of them will not come off and we do not want to gaul them. Some rigging information from Beneteau indicates that the upper terminals may have been put together with Locktite. We do not want to hurt the metal with too much heat so maybe we are not heating them enough. We have used WD-40 to soak the ternminals with little result and are considering other solvents eg. acetone. Do you think that might work?
Is there one type of end fitting better than another for use with dyform?
Not a worry about the back stay - it is already wire and it is just for tuning since it is a fractional rig with swept back spreaders and mechanical adjustment.
MLD

[Brion Toss]

Hi again,
It would be tough to damage the metal with too much heat; you have to get it extremely hot to do that. Are the upper terminals fixed in "turrets" in the mast? If so, they almost certainly screw together through the mast, so you have to get the rod at right angles to the stick to unscrew. Have you tried that? It seems unlikely that acetone or anything else will help, regardless of the terminal type.
But what are the tangs? If they're turrets, they're not suitable for Dyform, so you could just install conventional tangs a short distance below.
And Bob, I can't figure how to respond to your question separately, so I'll say here that Navtec had some amusing dismastings with Dyform backstays before they discovered the cause: unlike 1x19, both core and cover on Dyform are laid in the same direction, so under load the wire wants to unlay. And unlike with a turnbuckle (a thoroughly cottered one), there's nothing to stop its doing so; it continues to unlay until something gives.
Fair leads,
Brion Toss

[Jason]

See techinical notice here:
http://www.navtec.net/support/technotice.cfm

best,

jason

[mld]

An update on our rig in Grenada - seems that heat was tried on the turnbuckles with no movement. Seems we are going to have to give up on our rod rigging and dyform was recommended. Does anyone know if you size the dyform the same as the original rod (if we had 10mm rod for our V1 and D1 would we use 10mm dyform in their place)? It seems odd that the wire would be as strong as the rod.

[Brion Toss]

Hello again,
Dyform is neither as strong nor as inelastic as the same diameter rod, but the whole idea of it is to approach rod in both categories. We always start by determining what the loads are, and choose the materials accordingly; the 10mm rod may or may not have been the right size to begin with, and there's no need to clone someone else's mistake.
Whatever rod size you actually need, it's likely that approximately the same size Dyform will be right ó rod is typically measured in yet another unit of measurement, the "dash" size, as in - 22 or - 4. Anyway, make sure of your loads, and choose accordingly. You won't, in any event, need to change pin sizes.
Fair leads,
Brion Toss