Combine stainless scruds with dynema ?

[Alf Lande]

My Maxi 108 from 1981 is masthead rigged ( Selden) with stainless wires. The mast is keel-stepped and has two in-line spreaders.
Some years ago I replaced all wires except the forward and aft lower scrouds (no seperate baby stay).
I want to replace the lower scrouds (the others scrouds are «new»), and I would like advice if the lowers can be replaced by dynema.
The reason is simply being able to do it myself. Can a rig have both stainless steel scrouds and dynema scrouds and still function safely? is there a risk of failure?
Please give me your views and advice.

Picture of the rig below:

[neilpride]

With wire you can DIY to, i wouldn't mix different materials with different rigging properties, either go dynema completely or switch to wire, in my opinion.

[thinwater]

Originally Posted by Alf Lande

My Maxi 108 from 1981 is masthead rigged ( Selden) with stainless wires. The mast is keel-stepped and has two in-line spreaders.
Some years ago I replaced all wires except the forward and aft lower scrouds (no seperate baby stay).
I want to replace the lower scrouds (the others scrouds are «new»), and I would like advice if the lowers can be replaced by dynema.
The reason is simply being able to do it myself. Can a rig have both stainless steel scrouds and dynema scrouds and still function safely? is there a risk of failure?
Please give me your views and advice.

Picture of the rig below:

The way shrouds work, they must all stretch in a similar way to keep the mast in column (straight). It is OK if the mast leans slightly to one side (it will), as long as the center moves 1/2 as far as the top; the mast will remain straight.



The challenge I see is keeping the mast tuned under load. The Dyneema will creep at a different rate and the Dyneema will need to be sized to have the same stretch rate as the stainless. impractical.





Mixing shroud materials will make this "dance" complicated. The backstay, for example, can be Dyneema and still have stainless shrouds. The dance is simpler and does not have be as well choreographed.

[psk125]

Thinwater's position sounds reasonable. A rigger or engineer should be able to figure out what size Dyneema would work, but paying them for their time might make the costs even out. (And I would always be worrying about whether they were actually right.) Many people use Norseman fittings for "do-it-yourself" stainless steel rigging.
Norseman swageless mechanical wire terminations are availible in eye, turnbuckle stud, fork, t-bar, shroud terminals and insulator configurations at Rigging Only | RiggingOnly.com

[Alf Lande]

Thanks for advice!
I was not aware that swageless T- terminals are available.
I will get T-terminals from Norseman for the Selden mast attachment, and «normal» swedgeless terminals for the turnbuckle attachment.

Thanks again for your advice.

Alf

[s/v Jedi]

Originally Posted by Alf Lande

Thanks for advice!
I was not aware that swageless T- terminals are available.
I will get T-terminals from Norseman for the Selden mast attachment, and «normal» swedgeless terminals for the turnbuckle attachment.

Thanks again for your advice.

Alf

Norseman is bankrupt. Try Sta-lok as an alternative