SV Seeker

[Drunkonwatch]

Assuming you are talking about SV Seeker, why would you think there is going to be a structural problem associated with welding ??
As you and I know, once the basic skill has been achieved, steel welds perform extremely well, and are largely over engineered in most situations.

Lack of structural analysis could lead to possible failures in an extreme situation, but from my observations, steel hulls rust long before they fall apart.

Cold welded aluminum house for one. Look close at those welds. like I said I’m no expert folded a few dozen aluminum boats is all. The basic skill lol 😝It is the duug thread if not structural than than just rolling over is your bet. I was trying to bring up a pool idea on the boat as a lesson and a mental exercise with a prize. I’m just not convinced the bow won’t crumple in extreme conditions it’s a feeling not a super computer calculation lol. He’s has done so much so wrong I won’t go into it. But place Your bets lol

 

[Drunkonwatch]

I can see some failures were n the alloys used for sure but really didn’t want to devote enough time to hearing him.

 

[Jim in Halifax]

If Dugg persists in trying to sail the Boat Shaped Object, the failure mode will be the inability to stay upright and/or recover from a knockdown without down-flooding. Structural failure may accompany or follow stability failure. Of course if he cuts the masts off and uses it as a motorboat, we'll be in the realm of structural failure before long.

 

[Drunkonwatch]

Maybe a Spread sheet for the bets. Here’s my kick on da booty plus a bottle of Alaska vodka. Shipped to the winner.

 

[noaano]

Sextants and condoms share a similar price point/value for money ratio equation… Most folks that buy and rely on them, dont wanna suffer the consequences should they fail.

A brix sextant can be constructed for sub 5 bucks, though.

And beats any "real" / commercial sextant in accuracy.

 

[MR.CLEAN]

A brix sextant can be constructed for sub 5 bucks, though.

And beats any "real" / commercial sextant in accuracy.

WTF is a brix sextant

 

[opcn]

Can anybody explain how to replicate the Capsize Ratio = 0.68 published for Seeker on Marine Traffic, Sailboat Performance Specs, Vessel Details Wiki? I get ~1.5.

I entered virtually all of the information in that wiki. I probably had a typo somewhere.

Edit: Using the formula WLbeam/((displacement in pounds/64.3)^(1/3)) and assuming 154000 lbs for the loaded weight and 15' for the beam at waterline I get 1.12 . I expected this to be very good because she is massively overweight and the fact that he just stretched her longer meant that her beam was narrower than designed.

I have no idea how I got to .68 though, did not save the excel spreadsheet I used as a scratch pad for the math.

 

[Fah Kiew Tu]

Reasons You Want to Avoid Welding Stainless Steel to Carbon Steel​

1. Difficulty. Combining dissimilar metals together, such as welding stainless steel to carbon steel, adds extra challenges to the process. This translates into increased labor, rejection/error rates, and costs.
   
   
2. Hot Cracking of the Stainless Steel. Because it is more electrically-resistant than carbon steel, welding stainless steel with resistance welding heats up the metal much faster than with carbon steel. While waiting for the carbon steel to reach weld temperature, the stainless can overheat and become riddled with hot cracks. Using filler-based welding or preheating the plain steel can ameliorate this, but these methods aren’t perfect.
   
   
3. Thermal Expansion in High Temperature Service Conditions. Another problem with using dissimilar metals in a welded wire form is that thermal expansion from heat will affect each metal differently. This difference in expansion rates between the two metals can cause extra fatigue to the welded joint—reducing the wire form’s structural integrity and useful life.
   
   
4. Increased Bimetallic Corrosion. One of the reasons you generally want to use stainless steel is because of its strong corrosion resistance. An uncovered weld of plain and stainless steel that is exposed to extreme corrosive conditions, such as immersion in saltwater, could cause corrosion. This is because the intermingling of plain steel particles with the stainless alloy compromises the protective oxide layer of the stainless, allowing rust to form.
   
   
5. Reduced Weld Strength. Another problem with joining dissimilar metals is that it can lead to weaker welds—even with filler-based welding methods. The differences in weld temperatures and operational tolerances alone can easily compromise the strength of the welded joint.

To boil it down, welding dissimilar metals together is difficult to do right, and often produces inferior results to using metal alloys that are similar or the same.

Rubbish. It's done successfully all the time and isn't a problem as long as you follow prior art, using the proper gear and filler rods, shielding gas etc.

Some of those points are correct but the overall tone is far too full of doom IMO.

I have done a LOT of stainless (316L) to A36 mild steel welds and none of them have failed or look like failing.

FKT

 

[DELETED]

A brix sextant can be constructed for sub 5 bucks, though.

And beats any "real" / commercial sextant in accuracy.

https://en.wikipedia.org/wiki/Bris_sextant

ok… The “Bris sextant” is the Unformfit,unribbed,unlubricated,no teet,no frills survival condom… It’ll get the job done and probably withstand a dropping a washing and a reuse or 3.

Edit: Respect to Sven Yrvind for the design.

 

[Drunkonwatch]

Rubbish. It's done successfully all the time and isn't a problem as long as you follow prior art, using the proper gear and filler rods, shielding gas etc.

Some of those points are correct but the overall tone is far too full of doom IMO.

I have done a LOT of stainless (316L) to A36 mild steel welds and none of them have failed or look like failing.

FKT

We know it can be welded but can it go to sea?

 

[Zonker]

Assuming you are talking about SV Seeker, why would you think there is going to be a structural problem associated with welding ??

That's easy. Because he's fucked up virtually everything on the boat. Why is the welding any different?

Actually I think hull plating deformation in any sort of seas is more likely from what I have seen. It won't be the welds (well except where they attach to the "Frames")

His aluminum welding is often shit. Lots of grinding and re-welding makes it LOOK ok but it sucks. This jumped out at me during his latest video. Not nice even tightly spaced welds as he rotates the pipe but big blobs he grinds down.

 

[Excession]

WTF is a brix sextant

I think he's talking about this.

Bris sextant - Wikipedia

en.wikipedia.org

 

[Fah Kiew Tu]

We know it can be welded but can it go to sea?

FFS, almost every steel vessel out there has stainless welded to it somewhere.

And I only put in the 'almost' in case someone finds a steel vessel somewhere that doesn't.

Welding 316 to carbon steel using 309 electrodes/wire is a standard practice.

There's lots of scope for picking on Doug for stupidities but let's get real here, this sort of thing is just ignorant.

FKT

 

[Drunkonwatch]

when she starts pitching about you’ll be on board? I am skeptical is all I’m saying enough so that I won’t be on board if offered. I never once said anything about mixed metals I think the boat will heel wildly under 25knts putting extreme strain on a modified design. His overall welds will become a test then. The house and his aluminum will all crack I know it. I can bet may of his square fitments he wire wheeled the mill sheen off and then started welding are already failed. The one thing g I still don’t know was what the hull Plating is?

 

[Drunkonwatch]

She’s going to heel and buckle that’s my bet. Right after the mermaid almost midship.

 

[opcn]

The deck house is sitting right on top of the engine room that has transverse bulkheads in front of and behind it (and I believe the head compartment in the aft cabin also has steel bulkheads) so it's probably the most torsionally stable part of the boat. I wouldn't be surprised if the first gust of wind he gets into that mainsail overloads the poor welds because it is sheeted to blocks welded onto the edges of the cabin top but I think it is possible that the hull has never been stressed to the point where it transfers loads to the deckhouse and breaks anything.

My prediction for the end of seeker was that it'd face a condition like the bounty where Doug goes out to open ocean to keep from being dashes ashore by a hurricane and the bucking/sagging/hogging breaks open a weld seam on the other side of the cedar and foam and a relatively slow leak fills her up, shorts out the bilge pumps, and the vanishing stability leads to her dipping a rail in deep enough to flood the companion way and takes her down a lot faster than Doug realizes.

 

[See Level]

Hull plate is 1/4"

I figure the first real waves it gets into could go very, very poorly, stability wise.

 

[socalrider]

Best case failure mode is a freak 15kt gust on the beam knocks her down under full sail in 15' of water during one of his endless attempts to get the rigging sorted in light air. She down floods immediately and sinks to the bottom, and everyone kick-paddle kick-paddles to shore safely with no casualties. That's honestly what I'm hoping for. Still a messy salvage operation.

 

[peterAustralia]

I have followed this guy on youtube,,, but only became aware of this thread today. If I understand correctly, he built the boat, sailed it a little, found it to be tender, and then added weight to the bilge by pouring in lead. After that it was still too tender. we can assume it is tender because it has a high hull length to width ratio

My 2 cents worth is that he would be better off adding weight down as low as possible, by that I mean adding weight to the soles to the two bilge keels

Having an over sized propeller for the engine seems silly, are there not books that deal with all that? I am sure I read there is a formula,,, David Gerr(?) I am sure wrote something about this. If the propeller is too big, then maybe try a smaller propeller?

The placement of the tender at the stern is way too low,, assume he tends to fix that later?

Rake of the forward mast is just the way Chinese have always built junk rigs, there is a reason for it, sail balance or something,, IMHO it looks unusual but is a time tested way of setting the foremast

 

[MR.CLEAN]

we can assume it is tender because it has a high hull length to width ratio

is that what you can assume?