Legend Mast Tuning - pumping, new rigging

[baycloud]

Hey all, well long story short I got her sailed down the Oregon and Northern California coast safely to the SF bay. Don't have time yet to do a long post about it, but I will say that night sailing in the Pacific is truly something other-worldly!

She sailed beautifully as could be expected - brand new standing rig, decades old sails - both ripped a bit. Oh, and there was that minor issue that despite bringing 12 fuel filters, my fuel *line* clogged and I had to run the boat directly from jerry cans...and THEN siphon + filter fuel *back from the tank* while running downwind to make it in before some gales

Anyway, during some flogging I noticed while laying on the settee (ahem, of course I wasn't steering at this point), the mast would seriously pump forwards when the main sail went from flogging to catching the wind. It looked like a solid 6 inches, but keep in mind this is a brain that had gone many days with no more than 2 hours of sleep at a time. My rigger in Portland told me that he put the uppers at 11% tension, 10% on lowers, 12% on intermediates. Forestay was tighter, forget what amount. He said we should get it retentioned after the trip. I may have been using some amount of backstay bridle at this point; based on reading some threads, maybe I shouldn't have touched those?

Anyways, I have a loos tension gauge on the way. Also, has anyone measured/estimated the amount of bend in the mast at the dock? This mast is SO curved, it's like a banana, even sitting horizontally in the boatyard! Has a sweet look. Sails easily past 8 knots. Now let's get it setup properly. Any help/resources appreciated.

 

[fero]

You may want to go through this document, some good points/hints.
http://www.riggingandsails.com/pdf/selden-tuning.pdf
Good luck.

 

[ben solomon]

Download the Brian Toss DVD on "Tuning your Rig". He did this on a legend 37.5 (the model I have). It is very helpful. I have the DVD. It is very good!!

Here is the link:

Amazon.com: Tuning Your Rig (DVD version) : Mark Herlinger, Brion Toss: Movies & TV

Find Tuning Your Rig (DVD version) at Amazon.com Movies & TV, home of thousands of titles on DVD and Blu-ray.

www.amazon.com

The document Fero sent is also helpful. Sounds like you had a great adventure!!!

Ben

 

[baycloud]

Thanks guys, I ordered the DVD and am continuing to read. To me it sounds like my upper shrouds are too loose. They feel like it.

Any updated opinions on using the backstay for these rigs? In other threads, folks were saying that it loosens the upper diagonals and reduces bend which could cause pumping forwards

 

[ben solomon]

What I have done in the past is sail on one tack, i.e. port tack and then tightened the leward shrouds, then tacked and tightened the other side. Some masts have pre-bend, and your may have that. The other thing to do is take the main halyard to a midship stanchion, and mark it. Then go to the other side and see if it is equal. If not, adjust the turnbuckles accordingly until it is equal on both sides.

Also, your jib halyard may be able to be tightened further. That will help with the headstay sag.

 

[baycloud]

Ok, this is dredging up an old post but I wanted to FINALLY come around and update it since it's been fixed and in case it could help someone else out there on the internet with the same issue. Basically, the B&R rig needs to be tuned differently. I read everything I could, including some papers on the 37.5 tuning - since our rigs do have backstays as well.

Long story short, I tuned it to 11%, 8%, 9% uppers/mids/lowers. I read how these rigs like to be tightened relatively evenly. I will probably up the mids to 9 as well when I recheck after this sail. FINALLY figured it out!

 

[baycloud]

Oh yeah - I agree with some other posters here that the backstay probably shouldn't be torqued down too much. Can't find my notes on tension, but I keep it very loose.

All measurements done w/ 2 Loos gauges.

 

[SV Maverick]

Hi Baycloud good to hear that you have worked the problems out. I am contemplating getting new rigging for my 94 40.5 also. It has the original rigging so it should be replaced. My observation about our current rigging is similar to your original comments. The mast has "a lot" of curve to it. We have a backstay also and it looks like all of the adjustment has been used up to keep everything very tight. In stronger winds it feels like the boat has excessive weather helm. Thanks for updating your findings. Curious to the cost also. Possibly message me if you want to share that information.

A few other issues have to be taken care of at the same time. Adding a wind transducer, getting the reefing lines to work more smoothly and hopefully finding the source of a small mast base leak. Probably a good time to evaluate the roller-furling also. I want to get this done before deciding to get new sails in a year or so.

 

[baycloud]

Lots of posts here on the mast base leaking. Someone installed an instrument cover as drip cup in n the cabin above the access plate in mine!
i show it in my video

I used butyl tape, and not sure if the yard did a drip loop.

Anyway, I don't have anything to hide, it was just under $14k with a new Harken Ocean furler, in Oregon so prices were reasonable. Parts alone were 11k. In the future I will consider a diy but glad I got this one done in a yard. Included other minor items like lights and lines.

Can't comment on weather helm, but I normally sail with a reef in the main here in the SF bay. It's a big main. My mast has just a small amount of rake.
BTW the first thing that broke in the old rigging was a backstay fitting. I wonder if someone torqued it down too much. I now have something like 5% tension. Forget exactly but it's very low.

 

[SV Maverick]

Thank you Baycloud! It is cool to see your working on a sister ship. Please keep on posting. We have done a lot of work to get Mav looking good. I did a modest lithium-inverter-solar install which really opens up the cruising range and functionality of the boat. Next year the Bahamas! LOL

 

[chp]

Ok, this is dredging up an old post but I wanted to FINALLY come around and update it since it's been fixed and in case it could help someone else out there on the internet with the same issue. Basically, the B&R rig needs to be tuned differently. I read everything I could, including some papers on the 37.5 tuning - since our rigs do have backstays as well.

Long story short, I tuned it to 11%, 8%, 9% uppers/mids/lowers. I read how these rigs like to be tightened relatively evenly. I will probably up the mids to 9 as well when I recheck after this sail. FINALLY figured it out!

I take it you're talking about the diagonals. For my 280 the manual doesn't give any numbers for the diagonals only about using them to adjust the prebend. For the upper and lower shrouds they recommend 20% of breaking strength. My sailmaker told me that the B&R rigs have to be tight.

 

[baycloud]

I take it you're talking about the diagonals. For my 280 the manual doesn't give any numbers for the diagonals only about using them to adjust the prebend. For the upper and lower shrouds they recommend 20% of breaking strength. My sailmaker told me that the B&R rigs have to be tight.

Not sure of your system but the 40.5 only has 3 shroud wires total, it doesnt have separate diagonal wires. I do like keeping my tensions lower, and yes probably they should be all a bit higher, but I'll err on the low side especiallyif my mast is balanced and not moving. I dont seem to have much headstay sag either.

Thank you Baycloud! It is cool to see your working on a sister ship. Please keep on posting. We have done a lot of work to get Mav looking good. I did a modest lithium-inverter-solar install which really opens up the cruising range and functionality of the boat. Next year the Bahamas! LOL

I have 600 Ah of lithiums waiting to be installed. Keep using the boat and if you're north, I'll assume you have a big off-season for upgrades and repairs


Do you have any pics of your solar setup? I just added 720w. Looks only ok, but works great

 

[SV Maverick]

Planning on another 300-400W flex cells on bimini and separate MPPT controller for a total of 800W for 400ah. Not really an issue of battery capacity, but how to get enough solar to charge it back up or break even after a few days. Only use about 15% of battery capacity per 24 hours depending upon solar input. With a 85A alternator and DC-DC charger (to protect the alternator) only charge at 15A at best. 400W under boom is an easy but not so efficient place to mount cells. The biggest power saver was reinsulating the refrigerator and freezer areas and designing a digital spill over freezer-refrigerator system.

 

[baycloud]

Thanks for the pics @SV Maverick. Interesting setup - different than mine. Gives me design decisions to ponder. I was planning on putting the lithium batteries below the aft berth where they are now. Also, I built a solar arch. Unlike many other boats, we have a pretty high freeboard and cockpit, and resultant seeming low boom. So my solar arch is at about the same level as the boom instead of what you often see - often the solar is above the boom.

Also, my dinghy stays where your solar lives - I'm planning on adding another 100w flexible on top of the dinghy. Maybe another 100 on the dodger.

Lastly, can you plz tell me how you did the fridge/freezer insulation? The only info on here that I've seen was drilling many holes from inside the fridge/freezer, then covering those holes. Was that your method?
My fridge/freezer is at about a 60% duty cycle at ~13 amps total, so probably draws 190 amp-hours/day

 

[SV Maverick]

The refrigerator (8 cubic feet) and freezer (5 cubic feet) are pretty big. The front and top opening door on the frig at least on my boat did not seal well. I sealed all the holes and plugged the drain hole. Built new foam floors (6 inches) and walls (1-2 inches) with foam board covering the door. Lined with reflective bubble wrap to make it easier to clean and provide a little more insulation. Makes food access much easier for my wife and improved insulation. The spill-over uses an oversized evaporator plate and a digitally controlled fan about 2/3 down the compartment that blows cold air into the refrigerator. There are three air return holes at the top for return air to the freezer. You can essentially build new insulation into the boxes because the volume is so big and improve efficiency. I decided to try the spill over first, but you could always install two evaporator plates and compressors. Not sure the cold plate system has much of an advantage any more but some regard it as the best. It is "cool" to be able to see, set and monitor the system with the digital controls. No more opening the door to see what the temperature is. Uses about 4.5 amps on a 65-70% duty cycle so about 75 amp-hours/day which is just about covered with 400W solar on a good day. The new insulation made it significantly more efficient. Works great, but having the two compressor system would be fine also. The freezer temp is set to 12F and the refrigerator 40F.

You will notice that most component refrigerator systems have "guidelines" for insulation thickness. If you don't improve the insulation you will probably be disappointed with the results. The other option is doing some cabinete work and putting a self contained system in.

Sorry I don't have any pictures of making patterns and installing the foam sheets or the final bubble wrap. Also put a sheet of bubble wrap on top of doors and thin flexible foam.

 

[baycloud]

Interesting - so you only use 1 compressor and do a spillover? I was considering that...it sounds like you accomplish the same thing I do with half the power?
And you didn't do any insulation outside the fiberglass box - all inside and reducing the overall space. I was considering doing some of that. Thanks for you explanations! I would urge you to add this project of yours to the SBO website for the 40.5:

Hunter resources, by model

Hunter resources, by model

hunter.sailboatowners.com