Swinging spreaders

[nigelf]

If anyone with a moment to spare could assist with a serious gap in my slowly accumulating knowledge about modern N12 spreaders, I would appreciate that very much. My new Paradigm was collected with the spreaders on its Superspars carbon mast fixed by Rondar, apparently to avert the possibility of inverting the mast, although I knew even then that limited swing spreaders were probably universal. Most times when I have had the chance to look at other boats' arrangements the mast has been upright in the boat and with the spreader arrangement out of view. More recently I have seen a variety of settings varying from what appears to be removal of the inner fixing bolt, and the spreaders free to swing within the radius of the bracket to a more limited setting controlled by elastic round the front of the mast. Is there a recommended arrangement which could be described by a simple explanation? I tried to obtain information from Superspars but without response. I also assume that limited swing spreaders must go hand in hand with adjustable shroud tension - fortunately that is already provided and I have what currently looks something approaching the correct pre-bend setting of the rig. However the question of the swinging of the spreaders has me beaten for the moment.
 

[Jeremy C]

Nigel,

My new superspars mast arrived at the weekend so I have quickly taken a couple of pics of the P+B systen for swinging spreaders.
The white line which goes round the spreaders stops them from swinging forward too far, whilst the blue elastic encourages them back into place when you pull the shroud back on. Can see that with the elastic their might be a problem getting them to swing open in light airs, so might replace it with thinnner elastic. Images below to help explain:

[Kevin]

The line around the front of the mast (white in Jeremy's case) is standard, but I have never seen the elastic before and do not understand the need for it except possibly to stop the bolt from randomly rotating and self-adjusting the spreader angle. I have never had a problem with the leeward spreader swinging back to the correct position when reapplying the rig tension. My advice to Jeremy, and anyone else with a Superspars mast, is to replace those horrible wing nut bolts with a machine screw that is a little shorter with a nylock nut on the inboard end. The nut removes the self-adjusting feature and the shorter bolt reduces spreader poke and wear on the mainsail when the leeward spreader is allowed to swing (you will still need the chafe patches on the mainsail though).
 
Kevin

[Jeremy C]

Totally agree, the wing nuts are a real sail destroyer! It's not as if you need to adjust them that often, I was thinking of changing mine to nice round head allen bolts. Thanks for the heads up on the elastic, I'll remove it as I can't really see why it was there..

[grazz]

I cut off the wing nuts on ours and cut he bolt down so the whole thing is hidden within the spreader bracket. I simply cut a slot in the bolt that was left using a hack saw so it is adjustable with a screw driver. Seems to work pretty well but then I think our spreader bracket is deeper (being an Angel) 

Graham

[nigelf]

Very many thanks to you all. I have a little metal working to do but at least I know the general direction to go in and now understand why I have seen bits of elastic and other miscellaneous cords on some masts. Perhaps some enterprising person might come up with a spring-loaded adjustment screw device which would do away with the restraining cord.
Nigel. N3535.

[nigelf]

Since my initial post and subsequent helpful advice, I have assembled (thanks to P. & B.) a set of Superspars angle adjusters, machine screws etc. It seems that however you fit these there is likely to be a sharp edge ready to work its way into the mainsail, either by cutting off the head of the machine screw or simply leaving the head exposed. I was in RC yachting for some years and find I still have a good supply of shrink tubing, of which you use a lot in model yacht building and tuning and it comes in various sizes. Someone must have tried this already, but I reckon that one and perhaps two layers of this tubing over the end of the machine screw (or its original head) would encase the sharp edge neatly and of course it can be easily cut off again if you want access to the slot to make further adjustment to the settings. Is this too simple?
Nigel. N3535.

[Jeremy C]

pimped:

used shrink wrap tube to stop the spreader bolts moving, also has the benefit of holding the retaining string in place was going to use pan head bolts but could only find one long enough so cut down the originals as per grahams suggestion.

[Jeremy C]

no: 2