Mid-section of mast pumping when beating into choppy seas

[Blatunga77]

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!

[MarkJ]

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.

[goboatingnow]

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

[SaucySailoress]

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?

[savoir]

Tighten the aft lowers. The mast chock at the deck will probably have to be adjusted aft a little too.

[barnakiel]

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]

Originally Posted by SaucySailoress

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.

[tenchiki]

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).

[Bash]

Originally Posted by MarkJ

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.

[goboatingnow]

Originally Posted by Bash

+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

[Jim Cate]

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

[neilpride]

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...

[Blatunga77]

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

[JPA Cate]

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

[neilpride]

Originally Posted by Blatunga77

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.