Lead/concrete in bow

[macsail]

1984 Marine Trader 50,
We were about to install a bow thruster, and found a large poured lead/concrete fill in the forepeak below a fiberglassed cover. Drilled down at least 9 inches and all solid. I assume that the lead/concrete mixture was poured for weight and balance during construction. It covers a large area, extending back to the fwd water tank and appears flush with the hull.

The problem is that the yard in New Orleans is stumped on how to do the tunnel bore. Florida Bow Thrusters won't touch it either.
* Is this common for MT 50's or other trawlers to have this fill in the bow?
* Any ideas on how to do the bore?

I'm starting to think that I'll have a new bow thruster system for sale (past return date by 1 week).

 

[Max Simmons]

I was thinking possibly a concrete coring company, but you still have all the guts and stuff that's mounted in the boat, so I'm stumped.

 

[Comodave]

It might take a jack hammer to get it out. Maybe look at an Exturn bow thruster. It only takes 3 holes. But there might still be a problem with the length of the threaded tube length from the thruster into the boat.

 

[mvweebles]

Willards have ballast in the bow - concrete and steel punchings. I recently had a bow thruster installed. Crew used a rotary hammer (small jackhammer) to bust it up and remove - it all came out (800 lbs) The weighed the debris and it has been replace with lead ingots after the thruster went in. Lead is about 3x more dense so takes up 1/3rd the volume for same weight.

Peter

 

[Jeff F]

I was thinking possibly a concrete coring company, but you still have all the guts and stuff that's mounted in the boat, so I'm stumped.

The stuff would all be on top of the tube though, right? The top of the tube could be at/near the surface of the fill.

Not sure you'd find anyone to take that on though

 

[Comodave]

Willards have ballast in the bow - concrete and steel punchings. I recently had a bow thruster installed. Crew used a rotary hammer (small jackhammer) to bust it up and remove - it all came out (800 lbs) The weighed the debris and it has been replace with lead ingots after the thruster went in. Lead is about 3x more dense so takes up 1/3rd the volume for same weight.

Peter

That would work too...

 

[Jeff F]

Do you know how far you need to go down with the tube? It might only need an athwartships trench.

 

[Jeff F]

Also how's your trim as you use the boat now?

 

[O C Diver]

You have to remove the ballast in the area. It's not about making the hole, it's about fiberglassing in the tube. Most of the glass work is inside the hull for strength. You have to be able to reach all the way around the tube to do it correctly.

Ted

 

[mvweebles]

My ballast was pretty dense with the steel chunks. Not like busting-up regular concrete that once you get started it falls apart fairly readily. I think it took my crew (Mexico) two guys 1-1/2 days to get the old stuff out. It's grunt work - I'm sure they took several breaks. I found salvage lead at about $1.25/lb. Was actually more expensive in Mexico - I found it in the US for about $1.00/lb.

For my boat anyway, it's the type of job that you just have to bite the bullet and muscle through it. Trying to do a half-assed job by only removing part of the concrete would take longer in the long run and look like doo-doo in the end.

Good luck - please update with whatever you decide!

Peter

 

[Nomad Willy]

Peter,
I didn’t even know W30’s had fwd ballast. Is it under the sole at the foot of the berths?

I was at the boat today and I have corrosion at the joints on my heat exchanger. It appeared like strange ice formations. Wen’t down to work on it but 90% of the white stuff is gone but there’s a bad noise at the stern at about 1800rpm in gear. I’m worried it’s the shaft tube again but I have no leaking .. that I know of. Could befilling up the bottom of the lazarett I spoze.

 

[Comodave]

A concern if jackhammering lead and concrete mix out of the boat would be the lead particles getting dispersed throughout the boat. It can be very dangerous, ask the Flint residents. So take a lot of care and use protection.

 

[mvweebles]

Peter,
I didn’t even know W30’s had fwd ballast. Is it under the sole at the foot of the berths?

I was at the boat today and I have corrosion at the joints on my heat exchanger. It appeared like strange ice formations. Wen’t down to work on it but 90% of the white stuff is gone but there’s a bad noise at the stern at about 1800rpm in gear. I’m worried it’s the shaft tube again but I have no leaking .. that I know of. Could befilling up the bottom of the lazarett I spoze.

I can't speak to W30s. It's been about 25 years since I owned 1972 W30 hull 5 and I just don't remember what ballast she had and where. But my W36 definitely has concrete ballast forward.

Eric, not talking to you as I know you're a very knowledgeable owner. But for others - sounds like a small saltwater leak. I'm pretty sure you have a 4.107 or 4.108 on your W30 nomad. There is no such thing as a small leak

The above said, a few Willards have reported the aft concrete ballast shifting and messing with stern tube alignment. Not sure if you're referencing this?

Peter

 

[mvweebles]

A concern if jackhammering lead and concrete mix out of the boat would be the lead particles getting dispersed throughout the boat. It can be very dangerous, ask the Flint residents. So take a lot of care and use protection.

I believe fumes from molten lead are the big problem. Chipping should not be an issue but even just concrete dust is not healthy. Grinding would be a different story. A decent respirator/mask is definitely recommended.

 

[macsail]

Thanks all for the ideas… I feel ready for round two. Honestly I was a bit down.
The ballast will be necessary as I feel the boat level is correct.
I've been assuming it was lead in the aggregate (the yard told me that too). Steel was mentioned above, so I checked some pieces with a magnet…it's steel, very fine particles.
The block is very hard but cut easy enough with a 4" diamond masonry blade.
Sounds like the rotary hammer will do the trick, maybe with the assist of an angle grinder.
I don't want to cut out all of the material, which must be at least 800 lbs, but will suggest to cut a side to side channel. It has to be cleared all the way to the fiberglass on each side.

I will let you know how it goes. A picture attached.

 

[rslifkin]

If you need the ballast for trim, don't forget to account for the weight of the thruster. And if you want to add anything else heavy up forward (batteries, chain, etc) before you determine how much of that ballast is needed in the long run.

 

[DrissZougari]

Just make sure to weight whatever is taken out and compare it to the weigh for the thruster and battery (s).
good luck,

 

[mvweebles]

A couple pictured of ballast coming our of Weebles. I believe it to be in the 225 lb Sq ft range. Your guess of 800 lbs sounds about right given the Pic.

I would think an angle grinder would go dull shortly after hitting metal. Rent a Makita roto hammer from Home Depot and see how it goes. Don't be bashful. Stem/bow is pretty beefy construction.

Peter

 

[tozz]

Willards have ballast in the bow - concrete and steel punchings. I recently had a bow thruster installed. Crew used a rotary hammer (small jackhammer) to bust it up and remove - it all came out (800 lbs) The weighed the debris and it has been replace with lead ingots after the thruster went in. Lead is about 3x more dense so takes up 1/3rd the volume for same weight.

Peter

A friend of mine has a new to him 57' Selene and it has lead ingots in the bow. In the anchor locker to be specific and they were causing drainage issues.

-tozz

 

[O C Diver]

Thanks all for the ideas… I feel ready for round two. Honestly I was a bit down.
The ballast will be necessary as I feel the boat level is correct.
I've been assuming it was lead in the aggregate (the yard told me that too). Steel was mentioned above, so I checked some pieces with a magnet…it's steel, very fine particles.
The block is very hard but cut easy enough with a 4" diamond masonry blade.
Sounds like the rotary hammer will do the trick, maybe with the assist of an angle grinder.
I don't want to cut out all of the material, which must be at least 800 lbs, but will suggest to cut a side to side channel. It has to be cleared all the way to the fiberglass on each side.

I will let you know how it goes. A picture attached.

I think you're going to be taking most of it out to have the working space around the tube (including underneath) to glass it to the hull.

Ted

 

[Nomad Willy]

I can't speak to W30s. It's been about 25 years since I owned 1972 W30 hull 5 and I just don't remember what ballast she had and where. But my W36 definitely has concrete ballast forward.

Eric, not talking to you as I know you're a very knowledgeable owner. But for others - sounds like a small saltwater leak. I'm pretty sure you have a 4.107 or 4.108 on your W30 nomad. There is no such thing as a small leak

The above said, a few Willards have reported the aft concrete ballast shifting and messing with stern tube alignment. Not sure if you're referencing this?

Peter

Hi Peter,
Thought you said they did. I don't think they have fwd ballast.

I have a 107 cu in engine but it's not a Perkey .. repowered w a 107 Mitsubishi.

Wasn't aware of the other owners having shifting ballast = problems. I may have that again. Wish me luck.

 

[Lepke]

If the thruster is some standard American size, there are companies that bore concrete and could bore thru the fiberglass, too. A tool rental company may have the tool (special drill and right diameter boring head).

 

[Comodave]

A boring will not work for a bow thruster tunnel since it has to be glassed to the hull inside the boar. You will need probably at least 6” around the tunnel to glass it in. You will need to chip it out so you will have room to work around the tunnel.

 

[South of Heaven]

Hmmm..... Maybe just give up on your hopes of a traditional bow thruster?? There are lots of external mounted options but obviously they aren't as powerful , especially on a 50 footer.

You could always add a beefy stern thruster....

 

[Comodave]

Hmmm..... Maybe just give up on your hopes of a traditional bow thruster?? There are lots of external mounted options but obviously they aren't as powerful , especially on a 50 footer.

You could always add a beefy stern thruster....

Yes, some of them are as powerful. Easily can power a 50’ boat. Pau Hana put one on his boat and told me it was wonderful. They are available in double thruster models if you need that much thrust.

 

[Marco Flamingo]

I don't think they have fwd ballast.

I walked away from a Willard 30 because of the fwd ballast. It was obvious that somebody had cut an access if the V berth floor to look at the ballast and then screwed the floor board down and covered it with carpet. It was a rusty pile of loose scrap that looked like punchings. I was uncomfortable with the whole look if it.

Not that one would need a bow thruster with a Willard. I'm old school. Bow thrusters are training wheels. They are great in the marina. Skippers who need them should stay in the marina!

Okay, I'm on by third beer.

 

[Comodave]

I walked away from a Willard 30 because of the fwd ballast. It was obvious that somebody had cut an access if the V berth floor to look at the ballast and then screwed the floor board down and covered it with carpet. It was a rusty pile of loose scrap that looked like punchings. I was uncomfortable with the whole look if it.

Not that one would need a bow thruster with a Willard. I'm old school. Bow thrusters are training wheels. They are great in the marina. Skippers who need them should stay in the marina!

Okay, I'm on by third beer.

I am glad you can tell everything about someone elses ability to dock, or maybe their ability to climb around the boat easily. There are a lot of reasons to have thrusters and maybe it isn’t the best idea to drink beer and then cast aspersions on someone elses abilities or issues.

 

[BruceK]

Not that one would need a bow thruster with a Willard. I'm old school. Bow thrusters are training wheels. They are great in the marina. Skippers who need them should stay in the marina!

Okay, I'm on by third beer.

Hmmm. I wonder how often the "third beer"(or the ones before and after it) contribute to posts that offend. I enjoy a drink, but PUI is not a good idea.
Nor is telling fellow members who see a need for a bowthruster they are unfit to depart the marina. I`d guess a substantial number of TFers have thrusters...
Marco,you could ask a Mod to help modify your post if it`s too late to DIY.

 

[O C Diver]

Bow thrusters are training wheels. They are great in the marina. Skippers who need them should stay in the marina!

Okay, I'm on by third beer.

So your saying that most of the self docking commercial vessels like the ore carriers of the Great Lakes have skippers that need training wheels? Maybe you should spend some time on boats larger than 30' and try navigating some tight channels in a marina with a significant current or high winds.

Ted

 

[Redhook98]

So is this under the V-Berth? Our layouts are similar (79 49ft MT RPH) in a lot of respects and I am looking to see if I have ballast in the same area. I also have a 75 gallon water tank under my bow area. I am a bit high in the bow and was thinking of lead weights and re-commissioning the bow tank (currently not being used).

Thanks all for the ideas… I feel ready for round two. Honestly I was a bit down.
The ballast will be necessary as I feel the boat level is correct.
I've been assuming it was lead in the aggregate (the yard told me that too). Steel was mentioned above, so I checked some pieces with a magnet…it's steel, very fine particles.
The block is very hard but cut easy enough with a 4" diamond masonry blade.
Sounds like the rotary hammer will do the trick, maybe with the assist of an angle grinder.
I don't want to cut out all of the material, which must be at least 800 lbs, but will suggest to cut a side to side channel. It has to be cleared all the way to the fiberglass on each side.

I will let you know how it goes. A picture attached.