MERLIN ROCKET FORUM

Topic : Carbon masts

I'm pretty much old school and the boats I sail have alloy masts.  Getting the right mast profile is important because different bend characteristics suit different crew weights, and sails are usually cut to suit a particular set of mast dynamics.

Now I've bought a Merlin with a carbon mast. From what I can see, most manufacturers just make the one carbon profile for a particular class. Do the dynamics change from one mast supplier to another (i.e, a SuperSpar is stiffer than a Chipstow etc)? Or is it that rig controls for carbon masts make the mast so controllable that different characteristics are redundant and that any spar can be controlled to suit any mainsail?

Sorry for such a basic question, but I'm that sort of a guy...


Posted: 10/06/2013 13:13:47
By: Derik Palmer
The characteristics of the different masts are different, and need to be combined with sails cut to fit the particular mast you have.


Posted: 11/06/2013 13:21:16
By: Ben 3634
Ah, good.  I was beginning to think that the first rule of carbon masts might be that 'we don't talk about carbon masts'...

Yes, I understand that different mast dynamics require sails cut to suit; no, really I do. I probably didn't explain myself very well to start with.

Utilising an alloy mast setup, most classes might have several different profiles to choose from the same manufacturer. On the FD I might have used a Gamma, or an Epsilon or for a very flexible setup a Nimbus, all made by Proctor. There was a similar choice from SuperSpar and multiple choices also from other foreign spa manufacturers like Goldspar of which I have no personal experience. But most carbon spa makers seem only to make the one profile. So; are carbon spas from a particular manufacturer all similar, relying on rig control to make the difference? Or are they all individually made to specific customer requirements?

There's a point to this line of enquiry. If I broke the Epsilon on my FD and didn't have the cash for a new one, I might have looked for a secondhand one; all else being equal, it would behave in a similar manner to my previous stick. But I see carbon masts being advertised on this forum just by the manufacturer's name; recently a C-Tech mast was advertised as just that, and while I hesitated about buying it to replace a less than perfect condition Chipstow because I wasn't sure what the name implied in terms of bend characteristics, it sold. Very fast, to someone who obviously appreciated immediately what was unclear to me. It might help newbies to carbon stickery if we could formulate some sort of table ordering the available Merlin offerings in terms of stiffness etc.


Posted: 11/06/2013 21:52:26
By: Derik Palmer
I don't really know enough about them to comment definatively, however my understanding is that Superspars are the stiffest, Chipstow the softest and Selden somewhere in between. Each manufacturer seems to make just one profile at a time although I think there is a MK1 and MK2 Selden the latter being a bit stronger. you now have high modulous masts being built by Superspars and Allen which are a smaller section and lighter but roughly the same as a Selden I think. There is at least one more High Mod mast being made but I don't know who by.

I am sure someone will correct any mistakes I have made with that rough guide to masts, but I hope it helps a little.

Oh and the C-Tech never really took off as Chris Lewns left the class before he proved how good they where. I think they where somewhere close to the Chipstows but I could be wrong. There are only a couple of them about and I doubt anyone will order another one. Not a bad mast though.


Posted: 12/06/2013 08:46:58
By: Jez3719
The raking rig removes the power element from rig choice - the choice becomes response style, budget and availability. 

** Egg sucking alert **
The rig is set for optimal power when upright (0 Rake).
As you get progressively overpowered just rotate the rig back - keeping the same shape.
When you get to 11 on the rake - then panic.

Remember to move the board up to match

A Superspars (white or black) will be less smooth than all the Chipstow based designs, but *much* better than any tin rig and *very* robust.

All of the popular Carbon rigs are fantastic - just some are more fantastic than others.

/Dave


Posted: 12/06/2013 17:37:20
By: DL 3554
As Dave sys the power is from raking but the gust response  - i.e. the bend allowing the leech to open spilling wind in gusts -  is determined by the stiffness and other characteristics such as diameter and wall thickness.
Maybe this is the choice that could be explored - Is a Chipstow quicker gust response than CTech and Superspars and the new high modulus? For lighter crew quick gust response is good, for the heavier then stiffer that give less gust response maybe better - some who prefer to sail using the ain and kicker to control the gusts more than he mast characteristics may not notice so uch diference between the masts!


Posted: 13/06/2013 11:15:46
By: Piers 3671
The NEW high modulus SuperSpars mast has similar bend characteristics to the Chepstow (bendy) – and is if anything even whippier (gust response).  (It is also just as "smooth" – whether in this context "smooth" means an even bend with no hard spots or if it refers to the surface finish.)

If you haven't seen one yet, we'll be at Whitstable 22/23 June.


Posted: 13/06/2013 17:54:55
By: Richard
What is the delivery time on these masts? Suspect they can't be taken off the shelf?


Posted: 14/06/2013 12:07:23
By: Mr X
Our shelf is a bit cluttered at the moment - if you want to drop me an email?

Dave


Posted: 14/06/2013 13:13:32
By: Dave Charlton
"High rig mast, with longer luff mainsail, will flex more than mast for shorter luff mainsail". Discuss.


Posted: 17/06/2013 10:44:33
By: ....
David C Thank you for your update on your shelf!!! However, I sail an old boat, pre-low bow tank. Many of the older boats that have been refurbished are sporting high rigs and are (old) hog stepped. How long does it take to make these longer masts and how easy is it to extend deck stepped masts? Many thanks,

X


Posted: 17/06/2013 14:51:19
By: Mr X
Has anyone got further info on the dynamic difference, benefits and drawbacks of the different rigs available or is the info here still pretty accurate.


Posted: 11/12/2013 17:22:05
By: Gareth Griffiths

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