S shaped mast, what do I do?

T

Travelling Westerly

Well-Known Member
Joined
20 Dec 2019
Messages
460
Location
Dorset
Visit site
Evening all, just had my rig tuned to take out a slight aft rake on my mast (in mast furler). Rigger has got rid of that but introduced a slight s shape in it now. He has warned me about it and says the reason is the bolts are siezed at the end of the spreaders and to release them he needs the mast down.

Questions are

1 Will this S in the mast cause any issues short term (its very slight) like weaken it etc
2 Dont understand the set up of bolts at the end of the spreaders, can anybody enlighten me
3 Anybody come across this before and manage to release the bolts without dropping the mast?

Thanks
 
To help you we will need more info.

Pictures of how the spreader ends are attached to the rigging and what material the spreaders are made from

Are there any rigging screws at the spreader ends

Are the upper and lower rigging seperate which connect to the spreaders or is it a single length from deck to mast attachment point.

There days its not unusual to have the spreaders bolted to the rigging but older ones like mine are.

My old spreaders were aluminium and I had to cut the ends off the spreader to disconnect the rigging.

I replaced my al spreaders with stainless steel tube with stainless steel end caps and bolts fitted with a grease.
 
How slight is 'very slight'?
Is this side to side, not fore/aft?
I would say a couple of cm on a mast that's 10cm across is somewhere near the max, but I'd listen to other opinions.
You should be able to sight up the mast track or groove and gauge the bend fairly acurrately.
Or pull a thing rope or wire to the masthead and see how it lies down the track.

The bolts at the ends of the spreaders clamp the shrouds, so the length from spreader tip to hounds (where the shrouds attach to mast) can't be adjusted.

HTH?
 
Thanks guys
Back home now so limited for info but so far;

  1. The S is side to side looking up the track, its not more than a couple of cm for sure. The first curve starts just above the lower spreaders, the biggest and last curve is near the top of the mast
  2. The speaders are Selden aluminium but thats all I know at the moment without going up. The end caps are black if thats any indication of anything?
  3. The rigger said its probably a good winter job to plan for so presume its not the end of my sailing season just yet?
 
Sounds like the rigger is saying it's OK for the rest of the season.
With having had a rigger look at it, you are being more prudent than a lot of us.
You could look at the Selden stuff on the web or even contact them if you need further reassurance.
Just my opinion, no warranty!
 
TernVI said:
Sounds like the rigger is saying it's OK for the rest of the season.
With having had a rigger look at it, you are being more prudent than a lot of us.
You could look at the Selden stuff on the web or even contact them if you need further reassurance.
Just my opinion, no warranty!
Click to expand...
Thanks Tern, was reading that the same way.. If I need to unstep it then I will, just could do without having to go down that route if somebody knows a way of freeing these off
 
I'm afraid I smell fish. The spreader end clamps are used to set the spreader heights/angles (so that the spreader correctly bisects the angle the relevant shroud turns through) and the type I think you have are normally nipped up before final tightening of the bottlescrews.

Spreader to mast angles change very little with final tensioning and so I can't think why he'd need to change them, unless the angles were badly wrong in the first place.

Anyway, assuming that the angles do need changing, and that the screws really are stuck, that's no reason to leave a bend in the mast - correcting a slight bend will have almost no effect on an incorrectly set spreader.

I've rigged and re-rigged more than a few boats, and find it surprising that a Selden screw is so badly stuck that the correct tool and a little oil won't shift it.

Was he short of time?
 
anoccasionalyachtsman said:
I'm afraid I smell fish. The spreader end clamps are used to set the spreader heights/angles (so that the spreader correctly bisects the angle the relevant shroud turns through) and the type I think you have are normally nipped up before final tightening of the bottlescrews.

Spreader to mast angles change very little with final tensioning and so I can't think why he'd need to change them, unless the angles were badly wrong in the first place.

Anyway, assuming that the angles do need changing, and that the screws really are stuck, that's no reason to leave a bend in the mast - correcting a slight bend will have almost no effect on an incorrectly set spreader.

I've rigged and re-rigged more than a few boats, and find it surprising that a Selden screw is so badly stuck that the correct tool and a little oil won't shift it.

Was he short of time?
Click to expand...
When I had my rigging renewed, the rigger set up the spreader angle with the mast down. When I queried this he made the comment that tensioning would make little difference to the angle as I was pulling the stay tight at the time. I learnt quite a bit from the rigger that day!
 
Boathook said:
When I had my rigging renewed, the rigger set up the spreader angle with the mast down. When I queried this he made the comment that tensioning would make little difference to the angle as I was pulling the stay tight at the time. I learnt quite a bit from the rigger that day!
Click to expand...
With a lot of spreader ends the clamp has to be tightened before the end goes into the spreader, so you've no choice other than to do it before the mast goes up (deck stepped anyway). Nearly all the ones I've done that just meant pushing the spreaders as high as they'll go in their root fitting and setting the end to suit. I think the OP has cleverer ends where the screw is available at all times. A fair few don't have any clamps at all.
 
Probably suggesting something you already know, but the best way of 'sighting' up the mast track/groove is to use a small mirror held at an angle against the mast rather than trying to look directly up the track. I always keep a small 'vanity' mirror with my rig tension gauge to view the mast track.
 
As has been said check the angles between the spreader and rigging.

If there is a big difference upper and lower angles, try tapping the spreader up or down to correct the angle.

I cannot see how the end caps on a continuous rigg can hold the spreader to an extent it cannot be corrected with a rubber mallet.

I also cannot see how a misaligned spreaders could put enough force on a mast to bend it. So it could be a permanent bend in the mast not a a result of the rigging tension or spreader misalignment.
 
Rogershaw said:
As has been said check the angles between the spreader and rigging.

If there is a big difference upper and lower angles, try tapping the spreader up or down to correct the angle.

I cannot see how the end caps on a continuous rigg can hold the spreader to an extent it cannot be corrected with a rubber mallet.

I also cannot see how a misaligned spreaders could put enough force on a mast to bend it. So it could be a permanent bend in the mast not a a result of the rigging tension or spreader misalignment.
Click to expand...

You obviously haven't seen how tight some people think the clamp has to be! (They only need to be nipped, as above some end fittings do a perfectly good job without clamps).

I don't see any suggestion that the spreaders are causing the bends. It's probably not relevant to this thread, but any slight and fair permanent bend below the cap shrouds can usually be eliminated by tweaking the relevant shroud pairs.
 
Last edited:
anoccasionalyachtsman said:
You obviously haven't seen how tight some people think the clamp has to be! (They only need to be nipped, as above some end fittings do a perfectly good job without clamps).

I don't see any suggestion that the spreaders are causing the bends. It's probably not relevant to this thread, but and any slight and fair permanent bend below the cap shrouds can usually be eliminated by tweaking the relevant shroud pairs.
Click to expand...


Yes I agree I think the spreader ends and the "corroded" end screw is a red herring in the mast bend.

As you say its more to do with the rigging tensions than the spreader to rigging attachment.
 
OK guys update, went up the mast this morning and used some WD40 on the threads, managed to free both sides up no problem. Rigger coming back to take out the bend. Not sure how to upload photos on here to show end caps.
Thanks for your help
 
You must log in or register to reply here.

Share this page

Top