We have discovered that our superspar carbon mast has acquired a fairly substantial pre-bend. I looked up it a couple of weeks ago while sailing and was mildly surprised at the amount of bend we were carrying for the tensions etc that we had. On taking it down yesterday to push the spreaders forward a bit we discovered that there is about 3" of static bend, when it used to be straight.

Has anyone else had this?  The mast has been on the boat in the dinghy park at HISC for the summer so it has presumably got quite hot, but there has not been any tension on the rig or puller - just enough to hold it up.

As much as working out what has happened, is working out to do about it! I have left it with the shrouds slack, and lowers and jib halyard on tight for the week.  Next move is to bring it home, and sling it up in the garage with a 'corrective' bend in it.  Failing that a visit to Jacko for him to 'cook' it somehow!

Any other ideas?  I know for a fact that ours is not the only mast in the UK to live upright on the boat!  Not least of my concerns is that as Measurement Man I know it is illegal to have a permanently bent spar!!! Do I feel vulnerable to criticism?  Just a bit.....

All donations gratefully received!

ATB

GGGGGGGG & Jude

Hi Graham

Have heard of this before but not experienced first hand.

Somehow it reads as if the mast may have post cured itself in the sun. Would be interesting to find out from Simon Bevin (Superspar), what temperature they post cure the mast at as would be surprised if the mast in the open air got anywhere near 100�C.

I'd chat to Alan and see if you could re-post cure the mast in his oven at a higher temperature. Make sure you strip the halyards and mouse them as not sure what excessive heat will do to the structure of the Dynema etc. Need to also check if the spreader bracket has to come off as not shure what the width of the box is.

Bye for now

Barnsie

I don’t know exactly how your mast is built but the SS ones we used in the 12s a while back had an aluminium track.  We had a couple of instances where the mast had a ‘nasty’ incident and the track was left bent.  The bend in the track applied enough force to leave a prebend in the carbon tube. Some success was had ‘bouncing’ them straight in the same was you did a tin rig in the old days.  Extra care required not to do anything nasty to the track.

Doesn’t sound like anything bad happened to your rig so it may be a completely different issue.

I have heard of this too. I am assuming yours mast is black. I know its stable doors and all that but that's why I have had all my carbon masts painted white.

I think that this depends upon the colour of the twig, we have seen dark blue gelcoats on mega yachts approach and exceed 100 degrees celcius in the strong sunlight. White does not seem to have so much of a problem, but does generate much greater surface temperatures that you might think.

Of course, we haven't had much sun .... 

Assuming all carbon construction and the ali track is a dead end, the only recourse is to heat the stick so that the epoxy starts to move. Back to bare pole and into an oven. As Barnsie notes, the key is to then post cure the restraightened stick to some percentage above the deflection temperature of the resin system.

Sorry to hear of this problem Graham - quite a worry.
For most of its 7 year life, when not in use my own Jacko mast has been kept in the shed casually hung horizontally on its(same)side, but with a fender hung on the cantilevered tip to stop me banging my head on it too often.  Because I thought this loading pattern might induce a permanent set I regularly check it by eye, but to my surprise it has remained absolutely straight.  Not much help to you now I know, but it might put others' minds at rest.
Dan

The superspar on Heaven Sent came from Elusive when owned by Hywel, is at least 10y old and has never been inside.  However it does have  a white coating and is still dead straight.

Guys. Not been on the forun for a while, however I bought a SS Stick from Matt Biggs earlier this year to put on 3582, which appears to have done the same. It does have an alloy track and I too have kept it outside this summer. Looks like I have exactly the same issue.

Whilst the colour of carbon masts may be part of the problem / solution (never under-estimate the heating power of our sun)I think there may be a more fundimental answer to this.

The earlier Superspar masts came from a different supplier. I seem to recall they came from New Zealand. Unfortunately I cannot recall from where I collected this piece of information. It may have been direct from Ken Brackwell or perhaps New Zealand as I have friends there in the marine industry.

I would think (Hope!!) that with the number of black SS masts around that this is attributable to a dodgy batch of masts/resin. It may be worth contacting superspars and seeing if they are interested?

I've just borrowed a SS mast which had a'similar' problem but in reverse!. When stepped with no rig tension, it was inverted and the only way of setting it up was to apply loads of puller against a nominal shroud tension. 
Just got my Chipstow back  -  it's beautiful.

Spoke yesterday to Richard at Superspars; he was not able to offer any immediate suggestions without seeing the mast, as you would expect.  Since we bought through P&B they are going to have a look this weekend (Sale of Goods Act contract chain..).  In the absence of any solution arising from that visit, I will have to work out how to get the mast to Super Spars during working hours for them to carry out an assessment.

Further updates in the common interest as I get them...

ATB

GGGGGGGG

I’m sure that the P&B boys will get the mast back to SS for you if required.  Hope you get it sorted, out of interest roughly when was this mast built?

I heard something very interesting about the Sale Of Goods Act yesterday...

The mast is about 3 or 4 years old - it has been lightly used, and kept principally as a spare while the Chipstow is used, until this season, when we have been club racing alot more.

GGGGGGGG

Graham sounds as if it is the previous generation as we used the first of the current generation on Liquid Dreams at the Pwethelli Nats. Mixing the alloy track with carbon stick has been a concern from my point of view due to different expansion contraction and memory characteristics. However, our one lives as a sparrow perch under cover nearly all year. So have yet to experience any problems. 
Would suggest post baking as pre previous post. Hopefully that should solve the problem.

Without wanting to sound like a broken record, Frank Bethwaite goes through a long explanation of the development of the 49'er in his latest book. He describes the developments of the Rev. 3 mast which had an ali track and was subject to variable bend characteristics. Solve the problem by removing the rivets holding the track on and gluing it on with sikaflex. Suffice to say that the Rev. 9 mast is all carbon.

Not sure whether this is particularly relevant to GGGGGG's problem, but seems like a known issue within the mast world.

Short update; Alan Bax had a look at the mast on Saturday, and thinking it might be a bend in the track tried to bounce it out.  When it made no difference whatsoever, the conclusion was quickly reached that this was a red herring.

The mast is going back to Superspars courtesy our local friend - further updates to follow...

GGGGGG

Let me know how you get on?
I  raced at BandFYC yesterday in bugger all wind and applied a "LOAD" of lowers , with minimul shroud/puller tension and it was still bent backwards!
I was thinking of taking it home this Wednesday to try the same thing, but will now wait!!!!!
Kev