Thinking About a Boat

SoonerAviator said:
I'm well aware of using robotic welding techniques, we use them in my company. It's still more labor-intensive than a fiberglass mold by a large margin, and still has to have a lot of welds/forming/cut pieces to be made in order to fab up something a simple as a built-in livewell or anchor locker. The fiberglass layup just needs some mat/roving laid down, resin/chopped fiberglass sprayed in and then vacuum applied. Entire upper/lower hull mold for a 40' boat can be done in a day. You aren't doing that with aluminum and robot welders unless you have an assembly line similar to a major auto manufacturer. Fiberglass materials are also much cheaper per square foot than aluminum.
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You forget all the mold making processes, prep, and the life of them.
Plus the cost of resin, has sky rocketed.
I've worked the marine industry as a part time job when I was active, and full time after.
and was amassed at ow easy the aluminum boats go together.
When you cut parts, you cut lots of 5 or 10, parts get tacked together by a cobramatic hand welder, then fully welded by a robot. hull construction less than a week.
 
SoonerAviator said:
Fiberglass materials are also much cheaper per square foot than aluminum.
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I really don't believe that. Hull layups are huge, thick, and require large amounts of material.
plus the thickness often requires insolation and second lay ups.

At over $1400 per drum for common laminating resin, $1.00 an oz, for catalyst plus all the other supplies. plus the layup tools chopper guns and the such. I really doubt it.
 
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OBTW
I'm not new at this.
 

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Tom-D said:
I really don't believe that. Hull layups are huge, thick, and require large amounts of material.
plus the thickness often requires insolation and second lay ups.

At over $1400 per drum for common laminating resin, $1.00 an oz, for catalyst plus all the other supplies. plus the layup tools chopper guns and the such. I really doubt it.
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Not sure how quoting bulk supplies rates for fiberglass is proof that a fiberglass boat will cost more than an equivalent aluminum boat, but good on ya I suppose. I really wouldn't be worried about the cost of chopper guns and such when you're talking about robotic welders. Same goes for the hourly labor rate for a person to run the chopper gun vs monitor the welding robots and inspect. Most recreational boat manufacturers use fiberglass for their hull materials, the better ones do it with composite material cores and no wood to rot. If there were a significant cost savings to use aluminum on a boat, it would be done. Aluminum/steel boats make more sense when there are fewer complex features to build. Having curved seating areas and rounded edges throughout a 30' boat is tedious to replicate with metal, and ends up with a lot of wasted material. All of those features are easily created at one time with a fiberglass mold during the initial hull/deck forming. Boats of a more utilitarian nature are easier to justify building out of aluminum because they rarely worry about having lots of curved surfaces. Basic fishing boats (Jon boats, etc.) are one example where it's probably cheaper to use aluminum, as well as boats which are expected to see extreme duty and possible impacts (ex: river jet boats). The market shows that.
 
For my purposes, this is simple.

Fiberglass. That's what we'll be buying whenever we get around to buying another boat.

There, done. :)

But given that the requirement has been made to finish some of the other projects first (including the house), I'll just be doing the occasional browsing of CraigsList and Facebook marketplace for now.
 
I will admit that aluminum boats are usually utilitarian work boats, that do not have a lot of curved surfaces. but when you consider that each of the those curved surfaces requires a mold, you can add that cost to the build. (amortized over the number of copies)

During the late 70s I worked nights for a Radier Marine We were building a "bow Picker" fishing boat, which was a 16X36 tunnel hull landing craft. the mold preparation was 6 workers a week polishing waxing prior to shooting the gel-coat.
My point? there is a lot of labor in the construction of Fiber glass boat that is not part of the direct build.
 
Ted DuPuis said:
For my purposes, this is simple.

Fiberglass. That's what we'll be buying whenever we get around to buying another boat.

There, done. :)
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That is what's on the market. :)

Well except, there are a few very nice old wooden boats out there.
 
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Tom-D said:
That is what's on the market. :)

Well except, there are a few very nice old wooden boats out there.
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I love old things, and Henning recently bought an old tug boat that I find fascinating. Had an old diesel engine that has a 9" bore, 12" stroke, and makes 110 HP at 325 RPM (that is not a typo).

As fascinating as old stuff like that is, it is absolutely not what we want in this case for this mission, just like we have old tractors and an old bulldozer and love those, but the truck and Mercedes are both newer (although my wife's daily driver Mercedes is 10 years old).
 
Ted DuPuis said:
I love old things, and Henning recently bought an old tug boat that I find fascinating. Had an old diesel engine that has a 9" bore, 12" stroke, and makes 110 HP at 325 RPM (that is not a typo).
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That sounds like an old BUDA diesel. Lots of them were produced for the war effort and ended up in tugs .
 
Ted DuPuis said:
Just looked it up, it's a 1940 Atlas Imperial.

The boat's name is "Elmore":

https://oldtacomamarine.com/engines...4ndQPXGUIG_12V18SC8YCxI0W-l5Qg3s3R9fGldIX9xGc
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WoW! quite a few around Puget Sound, Don't know as if I've ever seen one, Wouldn't recognize one if I did see it.

I once bought an old 65' tug from a salvage sale owned by the state of Alaska, they had used it as a barracks barge for state workers, it had a 12 cylinder cat in it.
It had been in dry storage a long time, I coated the dry wooden hull with a slurry of micro beads, flox, and talcum powder, put it on with a spackling gun, smoothed it with a trowel, sanded it, shot it with gel-coat.
Friends still use it for a summer home in Southeast.
 
Tom-D said:
I will admit that aluminum boats are usually utilitarian work boats, that do not have a lot of curved surfaces. but when you consider that each of the those curved surfaces requires a mold, you can add that cost to the build. (amortized over the number of copies)

During the late 70s I worked nights for a Radier Marine We were building a "bow Picker" fishing boat, which was a 16X36 tunnel hull landing craft. the mold preparation was 6 workers a week polishing waxing prior to shooting the gel-coat.
My point? there is a lot of labor in the construction of Fiber glass boat that is not part of the direct build.
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The entire deck/floor/seating bases/engine compartment/storage compartments/etc. can be done with one mold. The hull/stringers/transom are done with a second mold. You join the two together, and then install the wiring/plumbing/upholstery/powerplant. I agree that the actual fiberglass layup with resin/chopper gun/rollers/etc. is labor intensive in terms of manpower, but is done fairly quickly and allows for much more complex structures to be formed/integrated than having to weld in aluminum piece by piece. Imagine building this watersports boat identically in aluminum, specifically the deck at 0:54s. The same process is used on 30' cruisers and speeds assembly and production.

 
Do you realize how much engineering, trial and fit time goes into getting that to work.

All that time has to be paid for.

At Radier we did the prototype /(PLUG) in wood, then pulled the mold, deck, house, and instrument panel all were separate molds. (we built 12)
They now build that same boat in a week.
 
Tom-D said:
Do you realize how much engineering, trial and fit time goes into getting that to work.

All that time has to be paid for.

At Radier we did the prototype /(PLUG) in wood, then pulled the mold, deck, house, and instrument panel all were separate molds. (we built 12)
They now build that same boat in a week.
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The R&D time/cost to CAD design a hull mold that gets used for a decade or more isn't too relevant to the production time/cost of making a fiberglass boat. They don't stand around for weeks/months waiting for a new mold to get built. If you want to amortize the R&D cost/mold tooling on a per unit basis, fine, but I bet from a production volume standpoint, it still wins out versus using jigs/molds and welding up aluminum. It also doesn't address the added time it would take to make all of the complex hull and deck designs out of aluminum since the fiberglass method allows for multiple complex shapes/cavities to be created simultaneously versus having to attach aluminum panels piece by piece. You reference Raider boats, which from a brief glance, are all utilitarian and use a lot angles and flat panels of aluminum to create the cabin/pilothouse/etc. If you were to try and replicate the soft curves and radiused edges that the modern recreational boats do, the amount of metal fabrication time would go way up.

I'm done discussing it, but suffice it to say that you can't cost-effectively replicate a modern cruiser deck/hull out of metal if you are building identical boats. If you want to see an aluminum cruiser that replicates a fiberglass cruiser, check out a Dickey. They are truly beautiful boats, with all-aluminum construction. However, they are in no way cost-comparable to a similar size fiberglass boat.
 
Clearly there's only one way to solve this.

Everyone shows up at my house. Two teams: fiberglass, and aluminum (make sure to bring your own materials). I'll supply the beer. Whoever gets done first will get to sing "On a Boat" on their boat.

On my lawn.


(had to find the non-explicit version since this is PoA)
 
SoonerAviator said:
The R&D time/cost to CAD design a hull mold that gets used for a decade or more isn't too relevant to the production time/cost of making a fiberglass boat. They don't stand around for weeks/months waiting for a new mold to get built. If you want to amortize the R&D cost/mold tooling on a per unit basis, fine, but I bet from a production volume standpoint, it still wins out versus using jigs/molds and welding up aluminum. It also doesn't address the added time it would take to make all of the complex hull and deck designs out of aluminum since the fiberglass method allows for multiple complex shapes/cavities to be created simultaneously versus having to attach aluminum panels piece by piece. You reference Raider boats, which from a brief glance, are all utilitarian and use a lot angles and flat panels of aluminum to create the cabin/pilothouse/etc. If you were to try and replicate the soft curves and radiused edges that the modern recreational boats do, the amount of metal fabrication time would go way up.

I'm done discussing it, but suffice it to say that you can't cost-effectively replicate a modern cruiser deck/hull out of metal if you are building identical boats. If you want to see an aluminum cruiser that replicates a fiberglass cruiser, check out a Dickey. They are truly beautiful boats, with all-aluminum construction. However, they are in no way cost-comparable to a similar size fiberglass boat.
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With aluminum boat, there are no jigs or moulds, simply shear the plate to size, maybe break it to angle, fit it up, tack it into place.

And these simple angle boats do the job just as well as any fiber boat, and when you run them up on the beach, no damage.

glass boat guy ,, OMG. !! some one scratched my gel-coat, call the boat Dr. get it washed and waxed while yer at it.

Aluminum boat trainee,"Hey Boss I hit a dock pole today" owner. " so What ?"
 
Crash a hole in a fiber glass boat, and an aluminum one.
See which one gets fixed.
See which one gets trashed.
 
One of my catamarans, hull broken nearly in 2 in a storm. Kevlar/carbon construction. I made a full repair with less than $100 in material and no special tools.

This boat woud be practically impossible to duplicate in aluminum, but even if it was, it was have been scrapped. The skill and tooling required for a fix woud have been far greater. Thats coming from someone with the tools and most of the skills to do that job.
 

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Tom-D said:
Crash a hole in a fiber glass boat, and an aluminum one.
See which one gets fixed.
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Like this:

glue-guns-R-us.JPG


This is one of the many patches on our aluminum hulled 'burn boat'. It's an empty hull with some metal grates inside that allows us to create controlled on-board fires for training purposes (using pallets and straw). We were just out last night drilling on boat fires using that hull:

FB8_burnboat_AB8.JPG
 
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Bacho said:
One of my catamarans, hull broken nearly in 2 in a storm. Kevlar/carbon construction. I made a full repair with less than $100 in material and no special tools.

This boat woud be practically impossible to duplicate in aluminum, but even if it was, it was have been scrapped. The skill and tooling required for a fix woud have been far greater. Thats coming from someone with the tools and most of the skills to do that job.
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Aluminum hull of that size would probably wouldn't need a repair.
You'd be surprised what can be stamped from Aluminum. Ever see a prop spinner?
 
A floating heliport, garage and home.. you can take the Cobra with you.

Look at the great tool boxes that come with it.!!

And with that crane you could start a Tv show about catching wild crabs in Alaska....
 
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Tom-D said:
Aluminum hull of that size would probably wouldn't need a repair.
You'd be surprised what can be stamped from Aluminum. Ever see a prop spinner?
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That hull weighs about 25lbs. 18’ long. Aluminum isnt gonna cut unless you build a pig.
 
Tom-D said:
Lots of methods to shape aluminum.
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Not for his purpose. Aluminum's fine for many things but I don't see it being used for racing sculls or smaller pure racing sailboats (short races- ocean/endurance races are something else). They don't build them any stronger than they need to be (weight). Large boats? Working boats? The equation changes in favor of aluminum for those. The material to use depends on the vessel and how it is used.
 
Cap'n Jack said:
Not for his purpose. Aluminum's fine for many things but I don't see it being used for racing sculls or smaller pure racing sailboats (short races- ocean/endurance races are something else).
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That type of boat is usually built by 1 off methods either cold mold or foam over.
Foam over-- start with a big block of foam, carve out a shape you like, cover it with glass, melt out the foam.
Now you have a boat, use it as a plug.
The aluminum method make a constant curve boat, use an English wheel. are a left and right sides JB weld them together . :)
 
Tom-D said:
That type of boat is usually built by 1 off methods either cold mold or foam over.
Foam over-- start with a big block of foam, carve out a shape you like, cover it with glass, melt out the foam.
Now you have a boat, use it as a plug.
The aluminum method make a constant curve boat, use an English wheel. are a left and right sides JB weld them together . :)
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The only thing wrong with what you say is that they don't make the sort of boat I described from aluminum. You could make such a boat as you described from aluminum, but it would be heavy and slow compared to the composite boats- in other words, "a pig", to use @Bacho 's term.
 
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