Forums > Windsurfing General

Downhaul: actual vs. specified

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Created by jmac > 9 months ago, 18 Feb 2009
jmac
WA, 29 posts
18 Feb 2009 3:11PM
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Hi

I just got a new Severne Blade 5.3 and have a question on rigging it.

I rigged it up yesterday and pulled on the downhaul until I saw a crease that covered ~ the back 1/3rd of the top silver panel. I then outhauled it until all of the battens were behind the mast. It still had good body to it, and felt great when sailing. My problem is that I ended up using much more downhaul and outhaul than specified on the sail.

I have a technolimits 66% 430 RDM mast, and the sail is meant to be used with a Severne redline 100% carbon RDM mast.

If I am using a different % carbon mast to the one specified for the sail, should I still be using the exact amount of extension specified for the sail? Or should I ignore the specs and just rig it to look the way I think it should be?

I am thinking that as my mast may be much less bendy to the 100% carbon one recommended, that I need much more downhaul to get the same shape in the sail.

Thanks,
John

FlickySpinny
WA, 657 posts
18 Feb 2009 3:56PM
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I can't comment on the specific sail or masts, but check out the IMCS for the mast and the IMCS recommended for the sail. IMCS is the measure of "bendiness".

The amount of carbon doesn't directly influence the bend characteristics - it's the IMCS you need to keep an eye on. More information here:

www.seabreeze.com.au/forums/topic.asp?whichpage=-1&TOPIC_ID=36902&REPLY_ID=226013

If the IMCS of the mast and sail match, then you're probably ok.

I suggest that you check that the mast cap on the sail (if it has one) is in the correct place. I have before now had to use loads of downhaul because the cap was 5cm further out than it should have been!

Another option is to check the mast extension you're using. I use a Chinnook extension on Naish sails, and always have to use at least 2.5cm less extension than the sails recommend - I believe it's because of the mismatch between manufacturers.

In addition, I don't tend to outhaul my sails until the battens are all behind the mast - you may be applying too much.

I suggest that you experiment and rig it as per the recommendation and try that - see how it feels...

Actually, I'd also definitely take it into the shop you bought it from and ask for their advice - I'll bet they've got some answers for you.

Don't take too much of the above as gospel - I'm no expert on rigging (I know how to put my gear together, but that's about it), and I have no experience of the Blade. Seeing as you're in WA, you could probably get straight onto Severne themselves - I'm sure they'll sort you out.

Let us know how you go - be interesting to find out what the deal is.

jmac
WA, 29 posts
18 Feb 2009 4:24PM
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thanks FS - I'll try a few different things with it, and take it into the shop to see what they reckon

Sailhack
VIC, 5000 posts
18 Feb 2009 7:47PM
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jmac said...

Hi

I just got a new Severne Blade 5.3 and have a question on rigging it.

I rigged it up yesterday and pulled on the downhaul until I saw a crease that covered ~ the back 1/3rd of the top silver panel. I then outhauled it until all of the battens were behind the mast. It still had good body to it, and felt great when sailing. My problem is that I ended up using much more downhaul and outhaul than specified on the sail.

I have a technolimits 66% 430 RDM mast, and the sail is meant to be used with a Severne redline 100% carbon RDM mast.

If I am using a different % carbon mast to the one specified for the sail, should I still be using the exact amount of extension specified for the sail? Or should I ignore the specs and just rig it to look the way I think it should be?

I am thinking that as my mast may be much less bendy to the 100% carbon one recommended, that I need much more downhaul to get the same shape in the sail.

Thanks,
John



Just be careful...I (manually, mind-you) pulled downhaul on a Severne NCX 5.5, that I'd used half a doz times max...It exploded along the 2nd batten, and halfway through the luff pocket! No-one this side of Melb (4hrs away) is able to repair it.

It's sitting in the shed in 2 pieces, and looks like it will be for a while.

[edit] Ok Mr red thumbs...I deserve that for posting a negative report on a brand, I actually really liked the sail, and Severne sails in general. I'm just p***ed-off 'cause it was bought new (from the year before's stock), and I only got 5 or 6 glorious sesh's with it (over 18mths, due to studies), then BANG! I sent it off to get fixed, and was given it back (after 6+ weeks) and that they can't fix it, and to try myself!

I guess after reading Bondallucci's post on a good-natured sail supplier, I was hoping one might turn-up at my door and say "here-ya-go, pick a new one!" [edit]

Leech
WA, 1933 posts
19 Feb 2009 12:29PM
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If the sail looks and feels right then it is right. Ignore the measurements.

However, by outhauling until all the battens are behind the mast you'll lose all the bottom end power.

Rigging with the crease 1/3 into the top panel gives good bottom end in marginal conditions. If there's good wind take it 1/2 way. The sail is more stable this way and has better top speed. Use the outhaul to trim the "belly" for more/less power. Min outhaul is ~3cm positive I reckon.

Haircut
QLD, 6491 posts
19 Feb 2009 7:28PM
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heya sailhack. that's a bit rough hey. was it a new sail? surely it must have some sort of warranty against this sort of thing? I've had the same thing happen to an all mono charger that had gone brittle from UV and sounded like a shotgun going off i think the stickyback lifts under the stitching and all the tension is put on the holes in the mono where the needle went through

Sailhack
VIC, 5000 posts
19 Feb 2009 11:03PM
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Haircut said...

heya sailhack. that's a bit rough hey. was it a new sail? surely it must have some sort of warranty against this sort of thing? I've had the same thing happen to an all mono charger that had gone brittle from UV and sounded like a shotgun going off i think the stickyback lifts under the stitching and all the tension is put on the holes in the mono where the needle went through


Mono's perfect! not even a crease, never seen sun (Vic remember) Anywho, my opinion is that the mono didn't have enough cover along the edge and it just pulled all the stitching through the mono out from the batten...no warranty, '06 sail bought late '07. Prob is, my main sail is a 6.5, so I hardly ever used it, now that I'm starting to play in waves in stronger winds, I need a smaller sail...(or sails)



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"Downhaul: actual vs. specified" started by jmac