Flat bottom V mod - Help with bracing please

So this is how far I've gotten so far. I was going to put Herculiner on the whole bottom but I have since scrapped that idea since I dont want the extra weight and you wont even see it once I put the storage units in it.

The top bracing I am thinking is shown in red. I hope to have side storage, front and back decking (decking not for standing, just storage and chairs) with the middle area open.

Any comment/suggestions on the top bracing?

My next question is how the heck do I secure the floor to the bracing? The green circles are where the benches used to attach to the floor. The boat is so old the bench-to-floor attachments broke off so the bottom of the boat wasnt secured to anything and felt sort of filmsy.

Id hate to have to rivet from the bottom, but if that's the solution so be it...just rather ask before i go punching holes in it. :shock: Or maybe I put a plywood floor in?? I need some serious help.

Also, am I describing this boat correctly: flat bottom v hull?

Thanks everyone!

I don't know what you would call your boat? I'm sure someone on here does and the will let you know. As far as your bracing questions.
You could weld and/or use an aluminum epoxy type product that would adhear items together. I'm talking a JB weld type material. I have used stuff like this with great success.

I would not drill thru the bottom if at all possible. Just creates more places for leaks. JMO

Good luck with your project.

I have heard a lot of folks saying the flex on an aluminum boat is too great for JB weld and have experienced it myself trying to use it on a transom brace - it cracks.

The best adhesive for our boats tends to be 3m 5200...

Could you explain a little more what you are trying to do with it though? If all those red lines are framing on top and you are trying to brace them from the bottom...(this is what it sounds like to me)...you don't actually likely have to use a fastener of any type. You could lay 2x4's on the floor so the broad side is facing upwards and secure your vertical supports to those. Once it is in place it won't be going anywhere.

I did not suggest wood framing because of weight. I was thinking more on the lines of less because of rated capacity. I don't know how big your boat is or what the weight capacity is, but it is something to think about. I like working with aluminum angle and flat stock because it is lite weight, does not rot and is easy to work with.

JD is right about JB weld cracking under certain conditions. I was just referring to it as an adhesive type material to help hold an item in place. I have used 5200, marine tex and water weld. They all have good adhearing qualities. I just like to attach things for a more solid foundation.

Just more ideas and opinions to think about. That's what I like about this site. Gather information and do what I want!

I'm pondering the idea of (stout) aluminum channel running crossways from gunnel to gunnel across the floor, but not fastened to the hull. Then vertical pieces of angle as supports, then horizontal on top - this time riveted to the hulk but well above the water line. Properly framed, I think it'd be solid.

Sounds like the same idea I was getting at.

If you can afford to do it in aluminum instead of wood it is certainly a better choice.

Easy to work with, light and never rots.

I was definitely thinking aluminum. I mostly fish in electric only (two lakes within 20 minutes of my house) so i am trying to keep the weight down.

So you guys think I can just use some 5200 and "glue" down the al. angle to the hull and it will be ok? That would solve all my problems if it would work.

Or have rubber sheet under the bottom edge to keep it from moving much if you don't want to glue it. If it were me, I'd try it w/no glue and only use it if I had to.

Yeah the rubber is a good idea...I don't think you will need to glue it once all the framing is in place...you are going to attach the top to the hull so you shouldn't have issue with the bottom moving...the vertical framing supplies support via pressure pushing down on it...that pressure should keep it's from moving.

The important thing in designing it to me would be to distribute that pressure across as large a surface as possible - this will protect your hull. That is why I would be bracing the vertical supports against a horizontal board of some sort on the bottom.
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