New Jon Boat Project

[Bob La Londe]

Jim Isaac (Rest in Peace) mentioned this site a long time ago. He used to be a regular on my fishing forums. Thought I'd stop by and give it a whirl finally. This board doesn't really seem like the right place for this, but I didn't see one that seemed better. If there is please move my post there.

I've owned a 2003 Waco 2050-16 since 2003. Its not a "bad" boat for as cheap as it was, and back then they offered it in a 35HP and a 50HP version. I've gotten a lot of use out of my 50HP version including an Angler of the Year award, but its a modestly flimsy boat and its been used hard. Its broken more than once, and been welded and reinforced more than a few times. I like it though. Its light and was relatively fast for a shallow runner. Its about done. Some years back it came off the trailer and tore the back end out of the hull. I welded in patches and it floats just fine, but I put a bit of a rake in it. It doesn't have the speed it once had, because you CAN'T trim it up at all without horrible porpoising. Yeah I know about shifting weight and using a prop that holds the water better. I've got a small fortune in props, and I shifted everything I could upfront. I even moved the cranking battery up front for a test run. Marginally I can get it stable at a tiny fraction trim up, but its only off the stop. Its not really trimmed up. Used to be it ran pretty fast at level trim. A plate mounted on the cavitation plate does nothing but slow it down.

I am not putting all of this out there seeking advice on it, but to show I know about these things, have tried them and really don't want to hear the same stuff over again. Yeah, I could derig it, cut out my patches, repatch it, and maybe get it close to where it once was, but I just don't want to. Its a beat up broken up patched up old flat bottom that I got more than my fair share of use out of (and I'm still using it). I just want to replace it. I didn't have a problem with just replacing it with another one. I already know its weak points and how to fix them so they won't break, but when I talked to Aloha Pontoons they refused to make me one with a 50HP rating. (I would still have to find a dealer to sell it to me.)

I looked around and I just can't find what I am looking for from anybody else. To heavy, to big, not enough HP without a console and they don't sell the console version without a full rig and motor, etc etc, etc...so I'm looking at a new build.

I have a few questions. "What's wrong with plywood?" is not one of them. I don't plan to use any. I may go with a castable or a honey comb or something else in the transom, but it will not by plywood. If you have a suggestion for something to take a look at or research please let me know as long as its not plywood. Can you tell I've read a few boat building groups? LOL. The first few replies tend to be "what's wrong with plywood?" when some says they don't want to use plywood. In my case its because I have a pathological aversion to plywood and would not be able to use another boat built with plywood. Again, other light weight transom materials to consider would be appreciated. I wouldn't say price is no object, but I would certainly have no aversion to paying a lot more than I would for plywood.

Knee braces, and stringers will all be aluminum. On the Waco the stringers were pressed into the hull. If I was building a V bottom the obvious answer would be to weld in stringers on the inside, but a flat bottom tends to skip like a flat rock. If you have time to maneuver you can trim down and use one of the chines like a keel to help in a turn, but that's touchy feely stuff. The pressed in external stringer on the old Waco certainly helped with tracking atleast when going straight. My first thought was to bend up some stringers and weld them on the outside. It would help with tracking, and NOT be a source of leaks from long term abrasion from skipping sandbars. It would add a little weight, but not that much. My concern would be whether there should be an attempt to make them water tight or just stitch them like I would on the inside. If I just stitched them would the weight of the water inside of them be significant when trying to plane out, get level trim and optimize speed. I've spent a lot of time thinking about it and I'm not really happy with any of my answers. The best answer would be to press stringers into the hull, but I really don't have the justification to build a rig to do that for just one boat. That's a pretty sizeable investment.

Gunwales are another issue. Are there decent 5052 or 5086 marine grade extrusions out there for backyard builders or are we forced to use 6061 and scab them together out of pipe or tube?

Well, I am sure I have offended somebody already. so I'll stop for now.

 

[Bob La Londe]

I notice in the pinned materials thread that the link for diamond plate in the first link goes to 3003. Is everybody settling for 3003 in their tread plate applications?

I did find some 5052 tread plate in one of my searches, but 1/4" (6.35mm) was the thinnest they listed. (To heavy for most of my applications.)

 

[CedarRiverScooter]

Nice write up. I would be concerned that an external rib, if it has much height, could tear a hole in hull if it gets caught on a snag. I have heard of guys getting hull material, rolled with the ribs, from boat makers. Not sure they do that any more but would be easier than welding angles on.

 

[Bob La Londe]

Nice write up. I would be concerned that an external rib, if it has much height, could tear a hole in hull if it gets caught on a snag. I have heard of guys getting hull material, rolled with the ribs, from boat makers. Not sure they do that any more but would be easier than welding angles on.

Stringers. Ribs go on the inside.

 

[eeshaw]

Have you thought any about adding floatation pods to the back of your boat to see if it helps any? I'd do my decking with 6061 and depending on what you have for supports underneath, that would determine the thickness.

 

[Bob La Londe]

Have you thought any about adding floatation pods to the back of your boat to see if it helps any? I'd do my decking with 6061 and depending on what you have for supports underneath, that would determine the thickness.

I have thought about flotation pods, but for a different reason. Primarily for displacement at rest. Well, maybe for a different reason. Different thought process, but maybe a difference without a distinction. Usually pods are added to boats to offset motor weight and/or to offset the loss of flotation from adding a pocket tunnel or jet tunnel. If you meant for my existing boat I do not think they would help as in theory they are out of the primary water stream at planing speed. Tabs might help, but I run some shallow water and sometimes have to jump out and drag the boat back the way I came. There are a whole host of decisions to make there.

My current flat bottom has 0.080 5052 flat sheet resting on the ribs and foam sheets between the ribs. Its not to bad, but over the years I have had to replace a rivet or two. I figured to do roughly the same. I'd weld it, except rivets are easier to remove if I have to do any work on it. I have considered using 5052 and Line-X coating it. I'd have to consider the weight.

My net goal is a light weight boat with reinforcements in the places most likely to break. Light is relative of course. The Waco weighs in around 300 pounds unrigged. Two of us were able to lift it onto the trailer when I bought it. If I could keep the new boat under 350 with a little nicer layout and reinforcements I'd be happy.

FYI: With the Waco in good shape I hit 46.2 MPH on the GPS on a couple occasions with a passenger and a light amount of gear with an 05 Merc 2 stroke. There was a light uniform chop on the water of about 8-12 inches and you could hear the air bubbles sizzling under the hull. Even now the boat runs better and is less likely to porpoise with a light chop. Under normal loads on flat water it used to run 40+. I know that seems insanely fast for a flat bottom jon, but its not. Like any boat you have to pay attention to conditions. I had originally rigged it with a 1990 Force 50 and it topped out at 32 with almost any load. Heck that Force pushed it to 18-19 mph with a blown head gasket pumping water through one cylinder. Took half a mile to get on plane, but that boat is almost on plane sitting still. LOL. One of my buddies told me he used to think I was exaggerating a little until one day in a tournament he saw me light up and head up river. Like I said in the first post. I'd just buy another one, prefix the bad spots, and rig it the same if they would sell me one with the same 50HP data plate.

P.S. Some of you know, but a big bass boat with a flat racing pad can also skip like a jon boat. It just does it a 70+ instead of 30.

 

[Bob La Londe]

I tacked on some aluminum sheet to my regular aluminum order yesterday. Truck comes on the 15th. Probably won't do anything with it for a while, but I had some extra cash after the holidays so I figured to get it while I can.

 

[benjineer]

Bob, I just finished redoing my front deck and some doors using PVC board. It is pricey, but it worked pretty well, it's light, and it will not rot. I got 3/8x4x8 sheets at Lowe's. I fiberglassed the larger areas and doors for some added rigidity, and it worked pretty well. I was originally planning to double up on the deck with glass between, but I didn't need to. That depends on what kind of spacing you have between the the structure. You will want to carpet it or put some vinyl flooring on it because it dents easily.

 

[Beaver Assassin]

I would use 1/8 x 1 x1 angle or maybe even 3/16 x1 x1 on the bottom slow taper the front and cap the ends just be sure to move around while your welding yes stitch it in like you said but keep stitching until its solid because if you just try to run it, it will warp horribly. I wouldn't be too concerned with the water being in them as the mud and gravel build up.

 

[Bob La Londe]

Well, after much more research then I've done in the past I did find a couple marine extrusions that I might be able to order. The ones I found were 6061 though. Not 5052. It's a freshwater rig so 6061 would probably be just fine, but I really have this bug that I want to keep everything 5052 or possibly 5086. About the only thing that I found that was a 5052 extrusion was schedule sizes of water pipe. I found several aluminum manufacturers that make it, but I haven't found a retail source for it. My regular aluminum supplier that I use for my business has 5052 sheet but all of their other aluminum is either 3003 or 6061.