Topic : Second Phase Tuning

So, first phase tuning was putting back up the stuff that fell off/broke/came untied/we forgot/was on backorder etc.

Second phase:
a) Slack shroud when I'm beating, how do I rectify or do I just ignore? Increase spreader length? If I want to tighten the shrouds anymore then I need to double up my purchase system since my jib halyard system kicks their butt.

b) Helm is very sensitive is there anyway to make it a little less sensitive? It steers at slightest crew movement, pull on jib sheet, change in wind etc. Some is down to rudder movement, is there any point in adding friction to the pins? Elastic band or somesuch hi-tech device.

c) Are the yellow Crewsaver bouyancy bags really 50% more bouyant than the blue Holt Allen variety as the manufacturers literature says? Our aft bouyancy is marginal to say the least, althoughy a 3rd strap may make some difference. Since we moved the bag attachment points lower in the boat our transom is out of the water but our CB case is about 1/2" under. Does this really matter? It does take some effort to get below it with the hand bailer.

Thanks again

It was 90F and 15-20 knots yesterday with getting the tail end of Tropical Storm Cindy! We got wet!

Posted: 11/07/2005 18:59:37
By: John, NY
a) slack shroud, tighten them up - more purchase required, or shorter shrouds.
Do not lengthen spreaders - will alter mast bend.

c) yes

b) try some mast rake -will give some weather helm.

Posted: 11/07/2005 20:33:54
By: not afloat yet
forgot - class rules say rear bags must have straps no more that 300mm apart - so minimum of 3

Posted: 11/07/2005 20:35:04
By: not afloat yet
I have been following your progress with interest.  It must be very difficult setting up a new Merlin from such a distance!

Tighten the rig tension so the leeward shroud is just snug when beating. The harder it blows the tighter the rig tension as a general rule.

The helm on a merlin is very sensitive - that is what makes the boat such a delight to sail in all conditions. You must sail the boat upright or you will get weather helm.

Buoyancy - it is normal for the stern to be at or below water level after a capsize. You open the flaps bear away and she should surface like a submarine - very impressive. The problem is if you capsize in little wind (easy to do at places like Salcombe) then you need a bucket! Three straps are a must on the bags.

Hope this helps - good luck

Posted: 11/07/2005 21:03:22
By: JC
John ditto above, the initial problem with setting up multipart systems is just to much string. It has taken me a day to get to the stage of being happy enough to cut the excess line off. The travel required for say  a 16-1 jib halliard is emence(16" in fact!!!) so it,s just a matter of spending time on the beach getting it right, leave the drysuit at home then theres no lure of sailing when not prepared.

I must say I have used a 'Loos gauge' to assist in initial set up looking for a base setting of 250lb on the forestay, this is lt/med airs I then expect to increase tention as wind increases always hoping the mast stays in one piece. I hope this helps and doesent confuse any other tips all the best Barry.
ps Loos gauges from Superspars & usual web chandlers.
& ps congrates on finishing your boat; many talk, few can or actually do it. Regards Barry.

Posted: 12/07/2005 07:29:07
By: Barry Watkin
Thanks for the replies.

I have yet to cut excess string off! Its neatly coiled and velcroed under the decking.

I think my main problem right now is that my forestay has too much purchase compared to my shrouds and when i'm running with little rake my shroud lines are immovable but I can always get a little more on the forestay. Hence I tend to end up running with too little rake. I have a very easy way of doubling up my shroud purchase so i'll do that, just need to get the hi-load blocks.

I'll also look at obtaining a Loos guage. Does it come with instructions on how to set a boat up or just on how to use the guage?

Thanks again

John, NY

Posted: 12/07/2005 15:07:04
By: John, NY
Are you trying to alter the rake whilst sailing down wind? You'll need to be samson to increase it.

Let shrouds off down wind , take up slack with jib halyard, then when back on the beat, let jib halyard off to set the rake and THEN tighten up the shrouds till leeward shroud is tensioned.

30:1 on shrouds should be ample.

Posted: 12/07/2005 15:58:29
By: not afloat yet
I set the rake with the forestay and the rig tension with the shrouds.  Full on my shroud tension, measured with a Superspar tension guage, is about 400 lbs

Posted: 12/07/2005 15:59:37
By: JC
My current shroud purchase is 12:1
My current forestay is also 12:1
I guess i'm thinking that since I tension both shrouds at once I need more...
Miles, [at least I think its Miles] I'm trying to tension whilst beating to get rid of that slack shroud. I can't move my shroud string an inch and I don't think I ran out of adjustment under the deck!

Now I know why I bottled out and removed the 1/4" pop rivets from my hounds replacing them with a 14" bolt going straight through both hounds and the mast!

Posted: 12/07/2005 16:27:37
By: John, NY
Lee shroud should not go slack - have a look at tuning guide on Dick Batt's site (

Also do not worry about transom under water after capsize - this is a device to allow geriatric helms to float over transom and into boat! Seriously, forget bailing and instead get boat going as fast as possible with flaps open and leave the water behind - it does work.

In the absence of wind, only recourse is either vvvv large bucket or a trip ashore.

Posted: 12/07/2005 22:10:28
By: RichardT
Found out!

Hi John, The diagram I sent you should give 36:1, can email it again if you wish.

My creation still in paintshop :(

Posted: 12/07/2005 22:37:03
By: Miles
After being nominated for the Radox award for the best bathtub when we capsized the Merlin and were totally unmanoeuvreable, we found the biggest problem is that the entire centeboard case is under water and it comes up the slot faster than we can get it out. Sitting the crew on the case with a thigh blocking the slot actually enabled us to get the boat going again and reduce the water level sufficiently. Any other bright ideas?

Posted: 15/07/2005 08:25:03
By: Another lady newcomer
I had this problem in my old Merlin and have a roll of bubblewrap the size of the slot tucked behind a webbing strap which can be pulled out and fits neatly in the slot and stops the water coming up.  Hope this helps

Posted: 15/07/2005 08:42:18
By: Garry R
Easiest solution is to add extra buoyancy next to the front tank.

The main trick is not to capsize, the problem does not then occur. I believe this takes a lot of pratice so get those extra buoyancy bags in until capsizes are a rarity.

Posted: 15/07/2005 09:52:53
By: Miles
So, a day or two ago we took her out and capsized her in shallow water with the bouyancy better anchored and moved down a little. Made all the difference, we floated with the transom about 2" [50mm] above the water even with me back in! Still have the problem of the CB case being under water but when the board is up we are well enough sealed that water ingress is slower than bailing and so we managed to sail dry in 5 minutes or so. Flaps and Andersons open and fully operational. Still think i'm going to switch to the Crewsaver bouyancy since its 50% more bouyant [?] and appears to have a better surfacing on it for wear resistance/puncture proofidity. We already have a leak in the Holt Allens.

Going to add 2:1 to the shrouds giving me 24:1 in total. I'll see how I handle that and change it to 3:1 if I need to. Thanks Miles, still have the diagram, i'm pretty much there just didn't add the leading 3:1.

Blocks: I have been using Ronstan 20mm [used to be 19mm] with Hi Load versions on wire and the leading block on a purchase system. Is a 20mm double OK for use as a leading block on my shroud system? What sizes are you guys using? I started using Ronstan after getting 50% off list for a bulk order with one of my suppliers so no logical choice was made as to suitability.



Posted: 15/07/2005 14:10:48
By: John, NY
Do Crewsaver really advertise that their bags are 50% more buoyant than the Holt equivalents? I think they need Physics lessons!?
A buoyancy bag works because it contains air -which is lighter than water. The amount of bouyancy (or force lifting the boat higher in the water) depends only on the volume of air in the bag which is underwater. Anchor points are important to keep as much of the bag underwater as possible.
But if you want more buoyancy just install a bigger bag.

Posted: 16/07/2005 06:44:10
By: tom collins
Crewsaver Bags are bigger, the measurement 36 x 12 is internal to the seems for crewsaver bags, actual bag size for Holt Allen

Posted: 16/07/2005 09:46:32
By: Gasman
It was the nominal vs actual dimensions I had assumed were to play in the Crewsaver vs H-A bag fiasco. Unfortunately the H-A bags are almost free they're so cheap but the Crewsaver ones... Ow! 75 bucks a piece! The next size up in the H-A's is much bigger.

Put the 2x multiplier on my shroud system, no difference. Seems we wiped out a couple of 500lb cheek block below decks and our system is jamming. Looks like a combination of insufficient nut torque and too small bolts (mm vs inches!). Going to go up a size in blocks and change the way they're attached. Oh well, kinda expected some teething problems. Just annoying because we missed the tail end of the Hurricane today [reasonable winds on very sunny days for us here in the Norh East, not the devastation they get down south].

Thanks again for the info, we'll be back in the water by next weekend with a better/higher purchase shroud system.

Happy sailing

John, NY

Posted: 18/07/2005 01:57:25
By: John, NY


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