Just in from Steve:
I will be spending the next two years on a refit (although the boat is in very good shape), as I will be casting off from Seattle in 2019 for Mexico, the South Pacific, and possibly a circumnavigation (it would be the 2nd time around for this boat!). =)
Steve
Thursday, May 25, 2017
Thursday, May 18, 2017
Seacock Replacement Lessons Learned
The following is a lightly edited email from Carl Miller, Saphria 35LN23.
Well, Saphira is back in her [Hawaii] mooring, about 30 miles each way to the yard. I did replace three thru hull fittings at this time. Total cost about $2000 counting the very expensive yard bill; 11 hrs labor charged. Based on the good condition of the thru-hull made the same way as the one that failed, I do not think the others in the boat require immediate replacement. But I will give you a rundown of each of the three since they each have a separate lesson learned.
I was unable to obtain either Groco or Perko fittings that have the built-in flange. The new fittings we installed with a 3/16” thick fiberglass backing plate, using 3M 4200 sealant inside and out.
1. This is the head discharge, the valve that broke. It is 1¼” valve fitting but connects to 1 ½” hose. (Disregard the plastic n=bilge hose). The shaft thatbturns the ball has rotted (dezincified) and the part that engages the ball had virtually disappeared.
Here are the guts to this valve. Note the slot in the ball where the shaft is supposed to engage. I wire brushed the ball, originally it was chrome plated but the plating was all gone, or covered by sealife crud—see separate photo. Even if the ball could have been turned the Teflon seals were chewed up by the roughness of the ball surface.
Somebody [John Mackie of John William 37VT68] mentioned these valves are not “full flow” --boy is that an understatement. Look at the reduction of the pipe size in the photo below—start with 1.25” ID pipe size (1.23 in2), then the nominal flow is a 1” diameter (.79 in2), then with the crud build-up in the ball which is pretty normal in a head discharge, the dia is .8” (.5 in2)— so the flow area of the valve is reduced by a third by the crud, and the nominal flow is already reduced by a third by the valve design. This doesn’t even consider the reduction from the 1½” ID of the pipe that is carrying the sewage. Use less toilet paper!
The hole in the hull was cut ¼” oversize for this valve, a mystery. The one above for ¾” thru hull (1” dia thread) is even more oversize. Here’s a photo of these holes and the hull thickness is clearly visible. I didn’t measure it but a safe estimate of the hull thickness here is 5/8”.
Hardest part to find was an elbow with 1½” hose and 1¼” pipe thread.
2. Now for the shower sump drain. This is a ¾” thru hull of the very same construction as the larger 1¼ valve described above. Since it was not damaged (note zero corrosion on the shaft) I was able to disassemble and see its interior design and condition. Happy to say that this valve could have stayed in the boat—it was on perfect condition except for the mineral buildup causing roughness on the ball. Plus there was a little slop in the handle which made it impossible to open the valve to full open as seen in the photos. Although the valve would still have worked, I am happy to have it replaced.
Here is how it works—the shaft has a square section on the end, this engages a slot in the ball and allows the turning motion. The shaft has a “head” which makes up to a Teflon seal inside the valve body; another teflon seal is on the outside under the spacer and handle, and the nut draws these to a seal. The ball is slipped into the valve body as the square section engages the slot. The valve interior has another Teflon seal both top and bottom of the ball; the top “nut” fitting makes up that seal, and has the pipe threads for the hose connection. No lubricating fittings. Electrical bonding was completed using a screw tapped into the valve body flange.
The toilet intake valve was also replaced. It seemed OK functionally, and it a more “modern” ball valve construction, but caution led to take it out and “look-see” It wasn’t any trouble to remove! Yikes only tree threads engaged the valve body to the thru hull. This was a result of the ¾” thru-hull threads being cut off too short; instead of a backing plate and a nut whoever installed this used a large brass washer and screwed the valve down to the washer and it is a wonder it held together. It is replaced with a conventional strainer thru-hull, with fiberglass backing plate and large bronze nut, and the new valve is threaded thereon.
In the photo you can see how little thread held this fitting into the boat—scary! Once again we found a problem BEFORE it happened at a bad time.
We could have reused this valve—it is perfectly functional-- but I will clean it up and keep it for a spare.
Pictures of completed installations coming on a few days.
Well, Saphira is back in her [Hawaii] mooring, about 30 miles each way to the yard. I did replace three thru hull fittings at this time. Total cost about $2000 counting the very expensive yard bill; 11 hrs labor charged. Based on the good condition of the thru-hull made the same way as the one that failed, I do not think the others in the boat require immediate replacement. But I will give you a rundown of each of the three since they each have a separate lesson learned.
I was unable to obtain either Groco or Perko fittings that have the built-in flange. The new fittings we installed with a 3/16” thick fiberglass backing plate, using 3M 4200 sealant inside and out.
1. This is the head discharge, the valve that broke. It is 1¼” valve fitting but connects to 1 ½” hose. (Disregard the plastic n=bilge hose). The shaft thatbturns the ball has rotted (dezincified) and the part that engages the ball had virtually disappeared.
Here are the guts to this valve. Note the slot in the ball where the shaft is supposed to engage. I wire brushed the ball, originally it was chrome plated but the plating was all gone, or covered by sealife crud—see separate photo. Even if the ball could have been turned the Teflon seals were chewed up by the roughness of the ball surface.
Somebody [John Mackie of John William 37VT68] mentioned these valves are not “full flow” --boy is that an understatement. Look at the reduction of the pipe size in the photo below—start with 1.25” ID pipe size (1.23 in2), then the nominal flow is a 1” diameter (.79 in2), then with the crud build-up in the ball which is pretty normal in a head discharge, the dia is .8” (.5 in2)— so the flow area of the valve is reduced by a third by the crud, and the nominal flow is already reduced by a third by the valve design. This doesn’t even consider the reduction from the 1½” ID of the pipe that is carrying the sewage. Use less toilet paper!
The hole in the hull was cut ¼” oversize for this valve, a mystery. The one above for ¾” thru hull (1” dia thread) is even more oversize. Here’s a photo of these holes and the hull thickness is clearly visible. I didn’t measure it but a safe estimate of the hull thickness here is 5/8”.
Hardest part to find was an elbow with 1½” hose and 1¼” pipe thread.
2. Now for the shower sump drain. This is a ¾” thru hull of the very same construction as the larger 1¼ valve described above. Since it was not damaged (note zero corrosion on the shaft) I was able to disassemble and see its interior design and condition. Happy to say that this valve could have stayed in the boat—it was on perfect condition except for the mineral buildup causing roughness on the ball. Plus there was a little slop in the handle which made it impossible to open the valve to full open as seen in the photos. Although the valve would still have worked, I am happy to have it replaced.
Here is how it works—the shaft has a square section on the end, this engages a slot in the ball and allows the turning motion. The shaft has a “head” which makes up to a Teflon seal inside the valve body; another teflon seal is on the outside under the spacer and handle, and the nut draws these to a seal. The ball is slipped into the valve body as the square section engages the slot. The valve interior has another Teflon seal both top and bottom of the ball; the top “nut” fitting makes up that seal, and has the pipe threads for the hose connection. No lubricating fittings. Electrical bonding was completed using a screw tapped into the valve body flange.
The toilet intake valve was also replaced. It seemed OK functionally, and it a more “modern” ball valve construction, but caution led to take it out and “look-see” It wasn’t any trouble to remove! Yikes only tree threads engaged the valve body to the thru hull. This was a result of the ¾” thru-hull threads being cut off too short; instead of a backing plate and a nut whoever installed this used a large brass washer and screwed the valve down to the washer and it is a wonder it held together. It is replaced with a conventional strainer thru-hull, with fiberglass backing plate and large bronze nut, and the new valve is threaded thereon.
In the photo you can see how little thread held this fitting into the boat—scary! Once again we found a problem BEFORE it happened at a bad time.
We could have reused this valve—it is perfectly functional-- but I will clean it up and keep it for a spare.
Pictures of completed installations coming on a few days.
Carl
Wednesday, April 26, 2017
More Detail on Bobstay Failure
This is the welded nut on the lower end. Failure occurred about ½ way inside the nut. Inspection would not have revealed an incipient problem. I suppose turning the nut would have broken the rod. The threads backed right out, no sign of stress near the threads.
Broken ends of the ¾” dia. stainless rod. Color is distorted by flash by crystalline structure is apparent.
No flash color here. Not much held the rod together! This failure was a long time in coming. The threads into the fitting are ugly but seemingly not affected by the fatigue.
The solid end fitting for the rod ends had no toggle, no way to dissipate sideways motion imparted by an anchor line rubbing on the stay, so there is no doubt fatigue caused the failure and water/salt corroded in the fatigue cracks. The top end fitting had no sign of stress.
The replacement was simple and inexpensive:
I hope this experience can keep somebody from the problem happening when it would lead to serious damage.
Carl Miller
Sunday, April 16, 2017
Exumas Cruising
Mike and Linda Wiens, Fairwind 41LN10, are cruising the Exumas. Read about their on going adventures.
Monday, April 10, 2017
Check Your Bobstay...
Just in from Carl Miller, Saphira 35LN23
In a fair breeze and a 110%genoa, the bottom end of our LN35 (1987) bobstay fractured. Since my local rigger said he had seen the EXACT failure in Hawaii on a 41 Lord Nelson, it makes me think there could be a design issue.
At one rod end, they drilled out a 3/4" nut, and WELDED it to the rod, so there is a hex to rotate the rod for tension adjustment. But the weld heat changes the metallurgy of the SST and with trapped salt under the nut, and some side flexing from the occasional anchor line rubbing, the fracture occurred inside the welded nut. The failure was clearly metal fatigue, and it was a long time coming. The fracture surfaces are crystalline looking, all dark and rusty across the fracture. Because the failure was occurring concealed behind that welded nut, there was nothing to inspect or a crack to see from the exterior. If you have a LN any size and the bobstay rod is OEM, please think about replacing it before something bad happens at a bad time.
In a fair breeze and a 110%genoa, the bottom end of our LN35 (1987) bobstay fractured. Since my local rigger said he had seen the EXACT failure in Hawaii on a 41 Lord Nelson, it makes me think there could be a design issue.
At one rod end, they drilled out a 3/4" nut, and WELDED it to the rod, so there is a hex to rotate the rod for tension adjustment. But the weld heat changes the metallurgy of the SST and with trapped salt under the nut, and some side flexing from the occasional anchor line rubbing, the fracture occurred inside the welded nut. The failure was clearly metal fatigue, and it was a long time coming. The fracture surfaces are crystalline looking, all dark and rusty across the fracture. Because the failure was occurring concealed behind that welded nut, there was nothing to inspect or a crack to see from the exterior. If you have a LN any size and the bobstay rod is OEM, please think about replacing it before something bad happens at a bad time.
Sunday, March 26, 2017
Peccatore 41LN29 For Sale
Hello!!
Here is Mauro, from Peccatore!
We are actually in Bonaire, heading to Puerto Rico, Virgin Islands, Turk and Caicos, Bahamas then Florida.
Unfortunately it's time to put Peccatore again on the market. If anyone around the Lord Nelson world is interested you can contact me on my e-mail peccatoreboat@gmail.com.
Below are some pics!
Thanks to everybody!
Tuesday, January 31, 2017
Ellida 41LN48's New Owners
I am happy to advise that my wife and I are now the proud owners of "Shadow" 41LN48 or as she now is "Ellida". She is now at the Newcastle Cruising Yacht Club marina [NSW, Australia], with a rebuilt bowsprit and a rigging upgrade. I will write more and send some photos when we have finished the renaming.
Kind Regards, Geoff Duce and Sidsel Grimstad
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