Re: Concrete&Metal Scrap Ballast in conventional wooden hull-structures
Denis Meier
MicroWave (will launch this year for sure)
--- Inbolger@yahoogroups.com, "david_shurr" <david_shurr@...> wrote:
>
> I just checked the price of lead. A little over $2/lbs w/free shipping. Makes a boat's cost go up. I'll just add a hiking board and have my friends sit on it out over the water.
>
> Here is just one of the many websites out there.
>
>http://www.rotometals.com/Lead-Ingots-s/32.htm
>
> David
>
--- Inbolger@yahoogroups.com, "david_shurr" <david_shurr@...> wrote:
>
> I just checked the price of lead. A little over $2/lbs w/free shipping. Makes a boat's cost go up. I'll just add a hiking board and have my friends sit on it out over the water.
>
> Here is just one of the many websites out there.
>
>http://www.rotometals.com/Lead-Ingots-s/32.htm
>
> David
>
> I just checked the price of lead.Hence the scrounging at tire stores....
> A little over $2/lbs w/free shipping.
When the tire stores sell the lead, they are selling at source or wholesale prices. Your $2/lb is retail. It pays to cut out the middleman if you can.
Here is just one of the many websites out there.
http://www.rotometals.com/Lead-Ingots-s/32.htm
David
1. - to use left-overs of the FIRESTONE rubber-roofing - raid the roofer's dumpster - and a modest batch of vulcanizing adhesive,
2. - to cut out and glue up a series of more or less custom fit dedicated shapes/mouldsbetween, say, floor-timbers,
3. - to pour the concrete/metal-scraps mix into to pre-determined height,
4. - locate one or two j-hooked lengths of threaded galv./SS rod in the curing mix and let set up.
5. - Then screw on threaded eye(s) and lift up that cured ballast segment,
6. - peel off/out the rubber 'glove' and reinsert the ballast segment
7. - and bolt it down with a metal or wooden bar for reliable duty as ballast.
Annually, lifting up each segment would allow inspection of wood structure and periodic application of anti-rot chemicals that can live with concrete. That rubber-roofing is very touch and can easily withstand pouring a few hundred pounds of conrete/ballast mix into it surrounded by hull-structure.
Susanne Altenburger, PB&F
----- Original Message -----From:vscopelandSent:Wednesday, February 02, 2011 5:58 PMSubject:[bolger] Re: Mohegan frindship sloop and ballastThat's a good idea, and a clean installation, although molding and pouring lead is not easy or cheap, or fast, besides the gases and danger of molten metal if the mold(s) leak - for an amateur at least. I suppose for pouring concrete one needs a mixer, but that could be borrowed...
--- Inbolger@yahoogroups.com, "Peter" <pvanderwaart@...> wrote:
>
>
> > My experience with iron/concrete ballast is that moist
> > from condensation or incidental rain tend to go between
> > ballast and wood and stay there, creating problems much
> > earlier than rust
>
> I did wonder about combining carvel construction (fairly flexible) with concrete ballast (monumentally inflexible).
>
> Bolger called for about 700lbs of ballast which is about a cubic foot of lead. If the lead were cast in trapezoidal prisms, they might fit comfortbly in the bilge, short side down. It might multiply the work if you have to build several different molds, but you might be able of find a single section yielding say, 4 ingots in the 175lb range that would fit, appropriately shimmed.
>
--- Inbolger@yahoogroups.com, "Peter" <pvanderwaart@...> wrote:
>
>
> > My experience with iron/concrete ballast is that moist
> > from condensation or incidental rain tend to go between
> > ballast and wood and stay there, creating problems much
> > earlier than rust
>
> I did wonder about combining carvel construction (fairly flexible) with concrete ballast (monumentally inflexible).
>
> Bolger called for about 700lbs of ballast which is about a cubic foot of lead. If the lead were cast in trapezoidal prisms, they might fit comfortbly in the bilge, short side down. It might multiply the work if you have to build several different molds, but you might be able of find a single section yielding say, 4 ingots in the 175lb range that would fit, appropriately shimmed.
>
> My experience with iron/concrete ballast is that moistI did wonder about combining carvel construction (fairly flexible) with concrete ballast (monumentally inflexible).
> from condensation or incidental rain tend to go between
> ballast and wood and stay there, creating problems much
> earlier than rust
Bolger called for about 700lbs of ballast which is about a cubic foot of lead. If the lead were cast in trapezoidal prisms, they might fit comfortbly in the bilge, short side down. It might multiply the work if you have to build several different molds, but you might be able of find a single section yielding say, 4 ingots in the 175lb range that would fit, appropriately shimmed.
My experience with iron/concrete ballast is that moist from condensation or incidental rain tend to go between ballast and wood and stay there, creating problems much earlier than rust
Somewhere someone writhed that " never leave inaccessible places in a wooden boat"
If the ballast bulks are removable, you can check, keep dry, or fix some soft spot in the hull
Amilcar
--- Inbolger@yahoogroups.com, BruceHallman <hallman@...> wrote:
>
> > for high density, and also steel punchings are used in marine ballast
> > concrete mixes.
>
> After I hit send to that last email, it occurred to me that using
> recycled automobile tire lead wheel weights at aggregate would be a
> real and cheap alternative. Where I live, you can go down to the
> local tire shops and they all have 5 gallon buckets where they collect
> the wheel weights they discard when they balance new tires on rims.
> The give these away for free or for cheap mostly to the people who
> make lead castings for bullets, or for fishing weights etc.. Put
> these lead wheel weights in the hold of Monhegan, and fill the
> interstitial spaces with cement slurry, and you would get a cheap high
> density ballast.
>
--- Inbolger@yahoogroups.com, "Chester Young" <chester@...> wrote:
>
> As a consultant in the marine engineering field doing shoreline
> revetment work I prefer galvanized grade 60 rebar to epoxy coated. 1st
> issue is that concrete does not adhere to the epoxy coating. Any chip
> in the coating is a vector for rust along the rebar, and when it does
> fail it tends to do so in large sections. Observation after failure has
> shown where long sections of rebar would separate from the concrete due
> to the epoxy surface being smooth. Fortunately there is not a lot of
> epoxy coated steel used in the private sector, bridges are a complete
> other animal with extensive installation procedures to eliminate
> penetration through the epoxy.
>
>
>
> Just my 2 cents worth, for what it is worth.
>
>
>
> Caloosarat
>
>
>
> From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com] On Behalf
> Of Eric Kramp
> Sent: Monday, January 31, 2011 9:45 PM
> To:bolger@yahoogroups.com
> Subject: [bolger] Re: Mohegan frindship sloop and ballast
>
>
>
>
>
> First time responding. In regards to concrete encased on concrete, it's
> important to remember that the concrete is protecting the steel while
> the steel is providing tensional strength. Concrete in water makes a
> basic solution, and steel tends to rust in an acidic.
>
> I've chipped away concrete from 50 year old rebar and the steel looked
> quite good. Large cracks, on the other hand, will defeat this
> combination.
>
> If I were in a position to build a boat of this size right now, I'd
> research epoxy-coated resteel. Bridge resteel is pretty inexpensive
> compared to bare steel, and would provide a low-oxygen environment for
> the steel.
>
> -Eric
>
> From Peter:
> >
> > It's not just concrete. It's concrete with embedded iron or steel
> > scrap. If the metal starts to rust, you are going to have a big mess,
> > so it's necessary to be sure the metal is entirely encapsulated.
>
> for high density, and also steel punchings are used in marine ballastAfter I hit send to that last email, it occurred to me that using
> concrete mixes.
recycled automobile tire lead wheel weights at aggregate would be a
real and cheap alternative. Where I live, you can go down to the
local tire shops and they all have 5 gallon buckets where they collect
the wheel weights they discard when they balance new tires on rims.
The give these away for free or for cheap mostly to the people who
make lead castings for bullets, or for fishing weights etc.. Put
these lead wheel weights in the hold of Monhegan, and fill the
interstitial spaces with cement slurry, and you would get a cheap high
density ballast.
Don
>the steel while the steel is providing tensional strength.Chester wrote:
>1st issue is that concrete does not adhere to the epoxy coating.Remember here, this is ballast, and the steel is there to provide
density to the concrete. Loss of adhesion and the resultant loss of
tensile strength is of no matter.
Economy is the issue I think, and high density concrete is the goal as
being cheap and easy to conform to the irregular shape being filled.
The more dense the mix, the greater the headroom possible in that tiny
cabin. I have seen the use of iron ore as aggregate in concrete mixes
for high density, and also steel punchings are used in marine ballast
concrete mixes.
http://www.marineballast.com/steel.html
http://www.marineballast.com/densities.html
As a consultant in the marine engineering field doing shoreline revetment work I prefer galvanized grade 60 rebar to epoxy coated. 1stissue is that concrete does not adhere to the epoxy coating. Any chip in the coating is a vector for rust along the rebar, and when it does fail it tends to do so in large sections. Observation after failure has shown where long sections of rebar would separate from the concrete due to the epoxy surface being smooth. Fortunately there is not a lot of epoxy coated steel used in the private sector, bridges are a complete other animal with extensive installation procedures to eliminate penetration through the epoxy.
Just my 2 cents worth, for what it is worth.
Caloosarat
From:bolger@yahoogroups.com [mailto:bolger@yahoogroups.com]On Behalf OfEric
Kramp
Sent:Monday, January 31, 2011 9:45 PM
To:bolger@yahoogroups.com
Subject:[bolger] Re: Mohegan frindship sloop and ballast
First time responding. In regards to concrete
encased on concrete, it's
important to remember that the concrete is protecting the steel while
the steel is providing tensional strength. Concrete in water makes a
basic solution, and steel tends to rust in an acidic.
I've chipped away concrete from 50 year old rebar and the steel looked
quite good. Large cracks, on the other hand, will defeat this combination.
If I were in a position to build a boat of this size right now, I'd
research epoxy-coated resteel. Bridge resteel is pretty inexpensive
compared to bare steel, and would provide a low-oxygen environment for
the steel.
-Eric
From Peter:
>
> It's not just concrete. It's concrete with embedded iron or steel
> scrap. If the metal starts to rust, you are going to have a big mess,
> so it's necessary to be sure the metal is entirely encapsulated.
important to remember that the concrete is protecting the steel while
the steel is providing tensional strength. Concrete in water makes a
basic solution, and steel tends to rust in an acidic.
I've chipped away concrete from 50 year old rebar and the steel looked
quite good. Large cracks, on the other hand, will defeat this combination.
If I were in a position to build a boat of this size right now, I'd
research epoxy-coated resteel. Bridge resteel is pretty inexpensive
compared to bare steel, and would provide a low-oxygen environment for
the steel.
-Eric
From Peter:
>
> It's not just concrete. It's concrete with embedded iron or steel
> scrap. If the metal starts to rust, you are going to have a big mess,
> so it's necessary to be sure the metal is entirely encapsulated.
--- Inbolger@yahoogroups.com, BruceHallman <hallman@...> wrote:
Have you read the
> chapter in his book Small Boats? In it he describe how the
> concrete/steel ballast is intended to give some structural strength to
> the timber.
Yes I have read it, it's of course important. After careful consideration is the best to follow Bolgerś instructions and use concrete as ballast.
I am now 56 years old, and if I become 85 years, the boat will still become fine with concrete ballast. After that it isn't my problem any more :)
Carl Andersen
> The keel siding is narrow, so unless you changed a perfectly drawnInteresting observations.
> boat it wouldn't lend itself well to outside lead.
> The concrete thing does work well, and has a strong tradition,
> but many of us have had the pleasure of removing garboards
> and getting that stuff outta there too.
There are several discussion of concrete ballast in William Garden's books. I suspect it's one of those technologies that is good for a certain number of years, and becomes a liability thereafter. Galvanized nails are another. Strip construction Novi-style is another.
It's not just concrete. It's concrete with embedded iron or steel scrap. If the metal starts to rust, you are going to have a big mess, so it's necessary to be sure the metal is entirely encapsulated.
>Usually, 90+% of the time, it is a bad idea to deviate from the plans,
> Thanks Scot
> Yes she is a beauty. I hope that one day I have money enough to build this beautiful boat.
> I will buy the drawingings later this year. And I will choose inside ballast of lead instead of concrete.
>
> Carl Andersen
especially those created by a master designer. Phil Bolger typically
had good reasons for the details of his designs. Have you read the
chapter in his book Small Boats? In it he describe how the
concrete/steel ballast is intended to give some structural strength to
the timber. Omitting that detail would require a redesign to add back
that lost strength, and would alter the center of gravity, affecting
performance.
Yes she is a beauty. I hope that one day I have money enough to build this beautiful boat.
I will buy the drawingings later this year. And I will choose inside ballast of lead instead of concrete.
Carl Andersen
--- Inbolger@yahoogroups.com, "vscopeland" <vscopeland@...> wrote:
>
> Interesting, as I rarely see much mentioned about the Monhegan. I did some searches here as well last year. I had to get the plans, and I received them a couple weeks before Mr. Bolger's death. I also found a nicely built Monhegan sitting on a trailer in Dana Pt., CA about the same time. The lines are beautiful in real life too. Anyway, she was designed specifically for amateur builders, and that's partly the reason for the ballast arrangement as I understand it. There is no other ballast option in the plans. The ballast pour forms the interior bottom also, so there are no exposed floors, etc. I would build it as drawn, personally, but inside lead, secured, would be another option. The keel siding is narrow, so unless you changed a perfectly drawn boat it wouldn't lend itself well to outside lead. The concrete thing does work well, and has a strong tradition, but many of us have had the pleasure of removing garboards and getting that stuff outta there too. On the other hand, this is a workboat really, and the build it to use it mindset will work many more years than I will! I now feel like boats such as these were eco-friendly in that they were left to die in some backwater, and the wood and iron going back to nature. Today we've got plastic problems and hunks of toxic lead. Built with good traditional means, these boats will outlast you. Something to think about.
> She's small, as I'm sure you've heard, and I now see her as something like an alternative to the Buzzards Bay boat. You could lay down, and sleep inside her, but you're better off enjoying that beautiful strip-laid deck. Her simplicity of rig really appeals to me. She deserves a mooring off a pretty beach: to be used often and decorate the waterfront.
> Scot
>
> --- Inbolger@yahoogroups.com, "Carl Andersen" <carl@> wrote:
> >
> > Does this design depend on inside ballast alone, or have the drawings been updated toe a lead shoe/keel?
> >
> > The original drawings are with inside ballast of concrete and irons. As far as I know are concrete and wood not a particularly good combination?
> >
> > Carl Andersen
> >
>
She's small, as I'm sure you've heard, and I now see her as something like an alternative to the Buzzards Bay boat. You could lay down, and sleep inside her, but you're better off enjoying that beautiful strip-laid deck. Her simplicity of rig really appeals to me. She deserves a mooring off a pretty beach: to be used often and decorate the waterfront.
Scot
--- Inbolger@yahoogroups.com, "Carl Andersen" <carl@...> wrote:
>
> Does this design depend on inside ballast alone, or have the drawings been updated toe a lead shoe/keel?
>
> The original drawings are with inside ballast of concrete and irons. As far as I know are concrete and wood not a particularly good combination?
>
> Carl Andersen
>
I once owned the hull for one of Peter Van Dine’s Tancook Whaler which had concrete ballast in a fiberglass hull. At some point in the past, water had gotten between the ballast and the hull and frozen, cracking the hull. Someone gave it to me and I gave it to someone else.
A couple of notes:
On Monhegan, Bolger says:
…she’s specially laid out from scratch to use inside iron set in concrete. Besides being cheap and simple to arrange, this has some real functional advantages, among others that you will never have the condition of the keel boats on your mind. Loose inside ballast will destroy a boat in short order unless it is carried inside a heavy ceiling, in which case it can’t be stowed decently low and is apt to shift when you need it most, but concrete, if it is well worked into all the odd corners, will usually preserve both the shape and the timber. I’m of the opinion that it’s not necessary or even good to paint or tar under the concrete, or that the wood needs to be dry for pouring and would be much inclined to pour while the boat is afloat so she can be trimmed as you go.
Small Boats
I Note that in an earlier design—Masterhand—and a later design—Yarrow—inSmall Boats, Bolger went with a lead ballast in the keel.
Friendship sloops and Tancook whalers originally used inside ballast. Since there is very little room inside Monhegan,, perhaps Bolger figured that using the available space for inside ballast made the most sense. I am unaware that he ever published another design using steel ballast set in concrete and it may be that what seemed like a good idea 40 years ago was one that didn’t pan out. Or not.
Either way, Monhegan is a gorgeous boat.
JohnT
From:bolger@yahoogroups.com [mailto:
bolger@yahoogroups.com ]On Behalf OfCarl Andersen
Sent:Monday, January 31, 2011
7:39 AM
To:bolger@yahoogroups.com
Subject:[bolger] Mohegan
frindship sloop and ballast
Does this design depend on inside ballast alone, or
have the drawings been updated toe a lead shoe/keel?
The original drawings are with inside ballast of concrete and irons. As far as
I know are concrete and wood not a particularly good combination?
Carl Andersen
The original drawings are with inside ballast of concrete and irons. As far as I know are concrete and wood not a particularly good combination?
Carl Andersen