Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 14-07-2013, 15:45   #1
Registered User
 
Blatunga77's Avatar

Join Date: Jun 2013
Posts: 3
Mid-section of mast pumping when beating into choppy seas

Hi!

I have a problem with my mast/rigg. It's pumping in the mid-section, especially when beating, and even more so if the main has a reef in it.

The boat used to have a baby stay, but the former owner removed this when he fitted the boat with a Hoyt bom.

Because of the Hoyt Bom,(which I very much like to keep), its not possible to retrofit the baby stay again.

-The mast has two spreader pairs, swept backwards about 6-8 degrees.

-Single lower stays

Anyone who has any ideas for solving this problem?

I'm thinking of someway to make the mast more rigid in the middle part. Maybe fitting a forward diamond stay,with a single spreader pointing forward of the mast. Could this be a solution?

Sorry for my poor English, I hope it's understandable anyway. :-)

Many thanks!
Attached Thumbnails
Click image for larger version

Name:	image-386208350.jpg
Views:	149
Size:	186.9 KB
ID:	64091   Click image for larger version

Name:	image-4046149433.jpg
Views:	148
Size:	295.2 KB
ID:	64092  

__________________

__________________
Blatunga77 is offline   Reply With Quote
Old 14-07-2013, 16:08   #2
Long Range Cruiser
 
MarkJ's Avatar

Cruisers Forum Supporter

Join Date: Dec 2007
Location: Australian living on "Sea Life" currently in England.
Boat: Beneteau 393 "Sea Life"
Posts: 12,828
Images: 25
Re: Mid-section of mast pumping when beating into choppy seas

Try a running back stay. Put a temporary tang around the mast. Rope, held up by a set of spreaders and down to an aft block and round the windward genoa winch.
__________________

__________________
Notes on a Circumnavigation.
OurLifeAtSea.com

Somalia Pirates and our Convoy
MarkJ is offline   Reply With Quote
Old 14-07-2013, 16:21   #3
Nearly an old salt
 
goboatingnow's Avatar

Cruisers Forum Supporter

Join Date: Jun 2009
Posts: 13,649
Images: 3
Hmm , I can't see running backstays being helpful , since these are primarily to counter head stay action.

Fundamentally, with the spreader arrangement you have there isn't enough fore and aft support for the mid section , which is why the baby stay was there in the first place. I'd consult the mast maker , but I suspect you'll have to reinstate the baby stay

Dave
__________________
Check out my new blog on smart boat technology, networking and gadgets for the connected sailor! - http://smartboats.tumblr.com
goboatingnow is offline   Reply With Quote
Old 14-07-2013, 16:35   #4
********* Emeritus
 
SaucySailoress's Avatar

Cruisers Forum Supporter

Join Date: Apr 2010
Posts: 8,236
Re: Mid-section of mast pumping when beating into choppy seas

Could you not install a split baby stay, so that it runs to new chainplates on either side, rather than removing the hoyt bom? BTW, what's a hoyt bom?
__________________

SaucySailoress is offline   Reply With Quote
Old 14-07-2013, 16:44   #5
Registered User

Join Date: Jan 2010
Location: Narragansett Bay
Boat: Able 50
Posts: 3,057
Re: Mid-section of mast pumping when beating into choppy seas

Tighten the aft lowers. The mast chock at the deck will probably have to be adjusted aft a little too.
__________________
savoir is online now   Reply With Quote
Old 14-07-2013, 16:49   #6
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,314
Re: Mid-section of mast pumping when beating into choppy seas

Removing the babystay was a mistake. This is why the mast pumps. Adding a diamond could help. But do you have space for a diamond there? It may interfere with your jib.

BTW I am with Saucy of how to sort it out.

b.
__________________
barnakiel is offline   Reply With Quote
Old 14-07-2013, 16:53   #7
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,314
Re: Mid-section of mast pumping when beating into choppy seas

Quote:
Originally Posted by SaucySailoress View Post
Could you not install a split baby stay, so that it runs to new chainplates on either side, rather than removing the hoyt bom? BTW, what's a hoyt bom?
Like on Island Packets - one used under a jib and often looking like a bent tube with its end swiveling in a hole just aft of the forestay.

Sorta kinda.

Now possibly obsolete if you have a traveler before the mast.

b.
__________________
barnakiel is offline   Reply With Quote
Old 14-07-2013, 17:56   #8
Registered User

Join Date: May 2010
Location: near San Jose, CA
Boat: Yankee Dolphin 24'
Posts: 113
Re: Mid-section of mast pumping when beating into choppy seas

The baby stay was there for a reason, which you just discovered... 2 options I can think of are to essentially put in a pair of forward lowers (don't have to be as strong as the existing lowers, but each should be no less than the old baby stay), or a pair of diamonds in a forward-facing "V" which the spreaders where the baby stay attached. Both of these options you really want a naval architect, or a reeaally good rigger, to design for you (even if you do the work yourself).
__________________
tenchiki is offline   Reply With Quote
Old 14-07-2013, 18:03   #9
CF Adviser
 
Bash's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: sausalito
Boat: 14 meter sloop
Posts: 7,260
Re: Mid-section of mast pumping when beating into choppy seas

Quote:
Originally Posted by MarkJ View Post
Try a running back stay.
+1. A set of Dyneema runners should solve the pumping. There's a good chance your mast already has attachment points for these, up near where the baby stay used to live. If not, a rigger can install this fairly inexpensively.
__________________
cruising is entirely about showing up--in boat shoes.
Bash is offline   Reply With Quote
Old 14-07-2013, 18:15   #10
Nearly an old salt
 
goboatingnow's Avatar

Cruisers Forum Supporter

Join Date: Jun 2009
Posts: 13,649
Images: 3
Quote:
Originally Posted by Bash View Post

+1. A set of Dyneema runners should solve the pumping. There's a good chance your mast already has attachment points for these, up near where the baby stay used to live. If not, a rigger can install this fairly inexpensively.
Without a inner stay , a backstay there could pull the mast out of column, be careful

Dave
__________________
Check out my new blog on smart boat technology, networking and gadgets for the connected sailor! - http://smartboats.tumblr.com
goboatingnow is offline   Reply With Quote
Old 14-07-2013, 18:18   #11
Senior Cruiser
 
Jim Cate's Avatar

Cruisers Forum Supporter

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 11,450
Re: Mid-section of mast pumping when beating into choppy seas

With swept back spreaders, it may be that inducing a bit more prebend will stop the pumping without any additional rigging. None the less, it seems likely that the baby stay was indeed there for a good reason!

Cheers,'

Jim
__________________
Jim and Ann s/v Insatiable II , lying Port Cygnet, Tasmania once again
Jim Cate is online now   Reply With Quote
Old 14-07-2013, 18:43   #12
Registered User
 
neilpride's Avatar

Join Date: Jul 2009
Location: in the world
Boat: csy 44 tall rig.
Posts: 3,099
Re: Mid-section of mast pumping when beating into choppy seas

Yes, runing backs without a fw stay is not a good idea in my view,probably mitigate the pump to some extent but without a stay pulling forward is ??? You mention a babystay before and previous owner remove it, time to set that babystay back in place .... iguess...
__________________
neilpride is offline   Reply With Quote
Old 15-07-2013, 07:10   #13
Registered User
 
Blatunga77's Avatar

Join Date: Jun 2013
Posts: 3
Thank you all for your tips! I talked to a rigger today and he came to the conclusion that the mast is probably a little to weak for its length (18,5 meter), so probably I will have to replace the mast tube and the spreaders. Maybe not if I'm only day sailing or sailing in secure waters, but my plan is to take the boat to Patagonia from Sweden. :-) So I guess replacing it will be best in the long run...

I also went out sailing for a couple of hours today, and attaching the baby stay, I could see that it helped a little, but the mast was still pumping when going to windward in 15-20 knots of wind.

Anyone who has any experience of replacing just the mast tube and the spreaders and keeping the rest of the hardware from the old mast?

Cheers
__________________
Blatunga77 is offline   Reply With Quote
Old 15-07-2013, 09:06   #14
Moderator
 
JPA Cate's Avatar

Join Date: Nov 2011
Location: aboard, cruising in Australia
Boat: Sayer 46' Solent rig sloop
Posts: 10,673
Re: Mid-section of mast pumping when beating into choppy seas

Is your baby stay adjustable?

Ours has a tackle on the bottom of it, so it can be tightened. I'm thinking, maybe just a little bit more tension on it would help, perhaps. Or, one could install a turnbuckle on it if it is wire. Also, one of our boats had a track for the baby stay, also for the purpose of adjusting it. Your setup will probably determine how you deal with it.

Good luck with it.

Ann
__________________
Ann, with Jim, aboard US s/v Insatiable II, in Oz, very long term cruisers
JPA Cate is offline   Reply With Quote
Old 15-07-2013, 10:36   #15
Registered User
 
neilpride's Avatar

Join Date: Jul 2009
Location: in the world
Boat: csy 44 tall rig.
Posts: 3,099
Re: Mid-section of mast pumping when beating into choppy seas

Quote:
Originally Posted by Blatunga77 View Post
Thank you all for your tips! I talked to a rigger today and he came to the conclusion that the mast is probably a little to weak for its length (18,5 meter), so probably I will have to replace the mast tube and the spreaders. Maybe not if I'm only day sailing or sailing in secure waters, but my plan is to take the boat to Patagonia from Sweden. :-) So I guess replacing it will be best in the long run...

I also went out sailing for a couple of hours today, and attaching the baby stay, I could see that it helped a little, but the mast was still pumping when going to windward in 15-20 knots of wind.

Anyone who has any experience of replacing just the mast tube and the spreaders and keeping the rest of the hardware from the old mast?

Cheers
You mean replace the whole rig? mast and spreaders? do you know the mast brand, maker? Isomat, Sparcraft? old Nirvana? how thick is the walls sections?

With single lowers some pumping is normal, is the mast a custom design and installation? Ask your rigger if is ok to set a couple of aft lowers plus the fwd lowers to get a double set of lowers in each side, the babystay normally is atached on top of the lowers , i mean if is the babystay have a good lenght , normally going higer than the 1 set of spreaders .

The set up is something like that , you loose the aft lowers a bit , tight the babystay to see some rake , tight the lowers , adjust backstay if you feel there is to much aft rake. With double lowers and a tight well set babystay your rig is solid no matter what, a thicker wall section spar is not going to be much diference , is a matter of well suported sections.
aka lowers and babystay. My opinion.
__________________

__________________
neilpride is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 00:21.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.