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Old 02-24-2018, 07:54 PM
bigfun bigfun is offline
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Default boat build

18'. 72"bottom. 90" beam. 28" sides. 1/8th" sheet.
Going to be outboard jet sled.
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  #2  
Old 02-24-2018, 07:58 PM
bigfun bigfun is offline
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Flipped it today
Going to start on transom tomorrow.
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  #3  
Old 02-24-2018, 08:19 PM
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Ironman Ironman is offline
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Nice workmanship.
No wrinkles in the aluminum.
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Old 02-24-2018, 08:22 PM
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midmosandblasting midmosandblasting is offline
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Going to be a nice river jon boat .With the jet do you run a lot of shallow river .
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Old 02-25-2018, 07:56 AM
bigfun bigfun is offline
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Nice workmanship? Thanks. I intentionally didn't show pics of my welds. I struggled for awhile. Some distortion, most from me relearning tig and applying to much heat. After 20' of tiggin and dipping tungsten i was much better at preventing distortion. Welds are definitely not professional quality. And i should have used a different joint fitup. The transom sheet joint was much easier to lay down a nicer looking weld. Going to be migging most of the interior.
Run mostly muskegon and manistee rivers. Lots of rocks in the muskegon and shallow most of the year.

Decided to fill with water today and check for leaks.
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Old 02-27-2018, 05:55 PM
bigfun bigfun is offline
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Found 4 leaks on first side i welded. Marked them for later fix.
Flipped boat and started on rub rails.
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Old 02-27-2018, 07:06 PM
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Wolfram Wolfram is offline
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Interesting. Thanks for posting up.

Did you use somebody's plan for that, or come up with it yourself? Will there be stringers to stiffen the hull lengthwise? What about the transom...torsion box, plywood core? And how much hp?

Sorry for the fifty questions, it's just that I've messed with glass boats, and plywood boats, and some wooden boats, but never anything like that. I wouldn't know where to begin.
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Old 02-28-2018, 01:26 AM
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Quote:
Originally Posted by bigfun View Post

Decided to fill with water today and check for leaks.
One way I have seen this done is to have someone inside with a blowgun on the seam, Another person on the outside with a spray bottle of soap and water. The high pressure air on the other side of the seam will blow bubbles from the smallest pinholes.
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  #9  
Old 02-28-2018, 03:24 AM
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How much power do you plan to run? Inboard or outboard? That's a pretty light hull for a serious river boat. Bottom of the hull should probably be 3/16"; perhaps even 1/4". Most river boats around here will use that thickness of material for the bottom and then weld on strips of 1/2" thick material. The 1/2" is drilled and tapped and a layer of 1/2" or 5/8" thick UHMW is bolted on to absorb the beating from rocks and bottoming out.

Do you have a plan for the internal stringers and ribs? Boats have a real tendency to twist which of course leads to weld cracking and premature hull failure. You need a substantial amount of reinforcement to make the hull rigid so it doesn't flex. The best I've seen are literally like a double hull with ribs and stringers sandwiched between the outer hull and the floor and inner plates.

Was there a reason for the nearly flat bottom and minimal V on the bow? Depending on the speeds you plan (or hope?) to run that thing is going to skate all over the water--directional control will be iffy at best. You can correct some of the problem by welding angles on the bottom to form strakes but for best handling you really need some hard chines at the outer edges of the hull bottom.

If you happen to be planning on running an outboard engine the transom needs to be substantially reinforced--how much will depend on horsepower. Even an inboard powered boat needs a good rigid transom to prevent flexing but it can be lighter than what you need for outboard power.

We've had a lot of experience building and repairing small aluminum boats so if you have any questions fire away...
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  #10  
Old 02-28-2018, 08:03 AM
bigfun bigfun is offline
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Not much of a plan, winging it mostly. Pics. and info.off internet and local boats. Learning as i go.
Hp will be in the 65- 85 at jet range.
The type of boats Lkiethr is referring to are the NW big river class 1,2,3, 4.... rapids. This boat will be on mostly flat water.
Basically a big jon boat.
2x6 tube in transom tied together in an L shape. with 2 vertical gussets and corner gussets.
2x2 tube stringers 1.5x1.5 tube ribs that will also run up the sides.
The bottom will have angle strakes .
Flat bottom because i want it to sit as high as possible. The rivers i fish are shallow, no biggy when on plane but sometimes you need to power up in shallow water and a squatty rear sucks.
The 1\8" bottom is plenty thick enough for mi. water. Skating in hard turns might be a problem but I've been in a few other similar boats and the skating only happened when we wanted it to, high speed hard turns. 30 years of running my present jet and have only skated when playing. All the local custom sleds have 1" angle welded with the v down I'm toying with the idea of welding them in the flat L position?
Thanks for feedback
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