A War of Attrition - Side Deck and Stern Hatches

Wis boz,
There are no rivets in the hull. There are two nylon thru hulls in the transom for the cockpit scuppers, a nylon thru hull that is threaded to a marelon seacock for the washdown intake (the seacock is bolted to a 3/8" plate bracket that is welded to the bottom skin), another nylon thru hull for the bilge pump outlet, and a fuel vent on the port side. The only fasteners (that I can think of) are on the plate over the fuel tanks (so it can be removed without cutting the deck), and the fasteners on the fuel fills, water fills, and the scupper drains.

The welding is not that hard. Anybody can learn given some time. I learned to weld to do the boat, so I didn't have any experience prior to the project. I still have trouble with vertical welds and the overhead welds. My welding machine is a pulsed mig system, which is great for doing a lot of welding on a big project, but is not so great for doing small, short beads on stuff like round tube. I like to compare it to a squirt gun. It throws a lot of bead fast, but you have to keep the torch head moving or your weld will clump up. I wish I knew how to tig weld to get nice welds on pipe and small projects.

If anyone is taking on an aluminum project I would suggest looking into renting a plasma cutter (or borrowing one). They are a super cool tool and make cutting metal so much easier and quieter than woodworking tools.

The boat should be powered in a few weeks so I will post more as we hook everything up and get it in the water.

- Neil
 
Neil, OUTSTANDING is the only word that comes to mind when I look at your build pics. I am very curious as to what size motor you are going to hang on her.
 
Neil,

It looks like you might have a new business opportunity...That is a nice rig you have there...How many hours do you think you may have in project?

Regards,

Kristan
 
If anyone is taking on an aluminum project I would suggest looking into renting a plasma cutter (or borrowing one). They are a super cool tool and make cutting metal so much easier and quieter than woodworking tools.


- Neil
Click to expand...


And they are safe. I have a Hypertherm Max45
 
Niel,
photos look great and I am sure you earned a few cold ones on the hot days last week. It looks like you are way past the turn the corner stage. I bet you can see the launch in your sleep at this point.

The diamond plate looks esp good on the deck.


Hope you get a break in the weather for the rest of the month as you rig it out.
 
Charlie,
We are putting a 150 hp Yamaha on the boat.

Kristan,
I don't have a good estimate of how many hours I have in it, but I think its quite a few. Although, a lot of those hours I spent working by myself so that kills my productivity. When my dad has been around to help me it goes so much faster. He can figure out problems much faster than I, so we can make a lot of progress in a short time period. I think if dad and I were able to work on another one full time, we could probably complete the hull in 2-3 months. But this project has been drawn out over the past two years. I didn't know much about building, welding, or aluminum in general so it has been quite the learning experience.

- Neil
 
William,

Just for fun pricing.

Neil said 2 -3 months W/ his dad so using 2 men, 8 wks, 40 hrs/wk times $40/hr we get $25,600 labor. Using his estimated hull wt of 2000lbs and a price /lb of $7 for 5052 plate and we've got $14,000 material. No over head costs or electrical rigging and we're up to $40,000 for the bare hull. Motor 150 hp @ $100/hp and it's another $15,000 for $55,000. What's a tandem trailer with breaks? $3500 - $5000??

Material - $14,000
Labor - $25,600
Motor - $15,000
Trailer - $ 5,000
Total - $60,000

I'm sure others can come a lot closer to what she'd have to sell for to be worth going into production but suffice to say Neil is building himself a heck of a nice rig.

Scott
 
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Scott,
at first glance I thought you might be a bit high,
but Then I thought about the SAFE Boats the Coast guard and DEP are using and I bet the government is paying close to 150 rigged.
So for a bare bones AL hull without a house and full electronics I bet you might be a hair low.
 
William,
There would be a ton of different factors that could influence the price of a hull like this, so it's hard to come up with a "final" price. Some of these could include:

1. Aluminum Alloy - alloy type can greatly affect price. You could use 5086 (our choice), 5083, or 5052. You could decide to use 5086 for bottom and side skins but then use 5052 for you cockpit floor and topside decking, although I would prefer to stay to one alloy type for the entire hull. 5086 has better corrosion resistance but 5052 is cheaper (this might matter less if it is a freshwater boat?). The 5000 series alloys are generally considered marine grade alloys, but even within the same alloy some materials are certified "marine grade" while others are not. To my knowledge, 5086 is the best. Its what the Coast Guard, Pacific, Black Lab, and I think Metal Shark use. All of these guys build nice boats and I got to believe there is a reason why they select that specific alloy (strength and corrosion resistance). Where as common 6061 has poor corrosion resistance and would not be a good alloy for a hull. There's a ton of info on the different alloys online if you are interested. The market bounces around too, so you can save if you buy at the right time. But its hard to schedule and predict.
2. Material thickness: 1/8", 3/16", 1/4" - the thicker the more expensive
3. Smooth sheet/plate versus tread - tread is pricier but isn't as much of skating rink.
4. Cutting services - you can have parts cut by a aluminum supplier with plasma or waterjet capabilities.
5. Welding - Are you welding yourself (do you have to buy equipment) or would you be hiring someone to do the fabrication for you?
6. Console/Deck/Steering/Engine components - You could go bare bones or go nuts with the latest and greatest. Example, 5" gps versus a 10" monitor. Make your own deck plates or buy some. All that junk can affect the price of the hull by a few thousand, easy.
7. Power - engines are pricey.

It would be really hard to predict the finish price of a hull unless you were able to make a fairly accurate list of all the different materials, services, and equipment you would require. And a lot of those decisions are nothing more than personal opinion or taste. I would estimate that if you were to buy enough 5086 for a 21' hull you would probably be looking at 10k or more for just materials (not including any cutting services). But that's just a guess. So I would think you would be up to 20 - 30k for a finished hull pretty quick. Personally, I know nothing about CAD software and industrial scale aluminum sales so it was pretty difficult for me to get things rolling. Any experience is these areas only serves to make the process easier, and potentially cheaper.
Hope this helps,
Neil
 
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