About to build some bow storage and have some questions

[jimmwaller]

about to build a small bow platform with a storage area, a little battery compartment, and a bait livewell. Just have a few quick questions:

1) I'm going to build the sub- frame for the platform out of wood. I've seen conflicting information regarding whether or not you can use pressure treated wood. Some people say that you can't use pressure treated wood an aluminum, some people say it's the only way to go. So pressure treated or not?

2) I see people using stainless screws and screwing through the hull. Then I guess you use marine sealant over the screws. But this makes me nervous.... I'd feel much better if I could use the sealant and then do something... else... as a backup. Is there anything I can put over the sealant? I've thought about JB weld, flashing sealant, just normal duct tape. And then, what do most people do, just leave the sealant just kind of sitting on the outside of the hull? Won't rocks or whatever scrape it off?

3) Anything else I should know before doing this? my basic plan is to build the subframe out of 2x4s and screw them in place from the outside, and then build the storage areas and seal them off, and then build a carpeted plywood platform to set over everything. Besides the screws going through the hull, I'm pretty confident. But also happy to hear any common pitfalls or advice.

Thanks in advance.

 

[jbcurt00]

Use aluminum not wood to build the frame and absolutely NO pressure treated lumber.

SS machine screws or aluminum rivets to secure the frame to the hull and the pieces to each other.

But, what aluminum boat, got pix?

Aluminum angle is available at most hardware stores and both HD and Lowes.

 

[jimmwaller]

Hi-
Will aluminum be strong enough to, like, walk on? I was planning wood because I know that a human can stand on a few 2x4s, but aluminum seems weaker. what size angle are we talking and how close together?

thanks

EDIT: and how would you attach angle with screws? Do you mean running it across, like joists, or maybe running it along the edge of the hull, or...? thanks

 

[jbcurt00]

Moved this over to the resto and building forum since you will be doing some boat work

Dig into the tin boat builds over here:
http://forums.iboats.com/forum/owners-groups-by-manufacturer/s/starcraft-boats

There have been lots of boat mods done w aluminum angle.

I said SS machine screws, those require nuts, not screws like you'd use w a wood frame.

Once you have a frame attached to the sides of the hull, lay in supports for the deck (yes, like joists) and attach a sheet of plywood to it, it'll be plenty strong.


But again, what boat? Got any pix?

 

[jimmwaller]

hi-
thanks for the move. didn't realize it should go in resto.
I actually don't know what kind of boat it is. I bought it off craigslist a long time ago, and the title says "spcn" which in california apparently means 'special construction' and the DMV lady at the time told me that they just use that sometimes when either the original manufacturer is unknown or not in their system. I can get some photos soon but it's at the storage facility right now! It's just your typical aluminum boat though. 2 bench seats and it sure looks like a bowectomy happened at some point. So now there's a big open space in front that I'd like to make usable.

So, I've been looking through that forum lately, and I've seen a few people using aluminum, but I can't tell how they're attaching the angle to the hull. So, for example, here (http://forums.iboats.com/forum/boat...lleye-project-70-s-sea-nymph-ss160-1668/page6) watermann shows some of his angle aluminum. It looks like there are two aluminum joist things that span the beam, but it looks like one is attached (riveted?) with brackets and I have no idea how the other one is attached. The brackets look flimsy, but are they stronger than they look? I'm just having trouble seeing how angled aluminum can form the frame for a casting deck, which says more to do with my stupidity than the quality of the replies so far.

No idea why I'm just not putting it together. I'm gathering that you're telling me to use angle aluminum running across the beam and then to put the platform on top of that, right? so... where the angle aluminum is touching the hull, how does one attach the aluminum to the hull? So sorry... i feel dumb!

Thanks!

 

[TruckDrivingFool]

:welcome: to the iboats dry dock Jim!

One of our favorite games around here is the "ID this boat" game so I'll 2nd JB's recommendation to post some pics. Pics will also let us see what you're working with and get you better ideas on how to do things.

You certainly can use wood (not PT) however since most tin boats are on the smaller side weight added is a consideration. Not just overall but how high it is added. With wood also comes rot so it should be sealed (paint, epoxy, FG, ect.)

For construction to avoid galvanic issues with AL you want 6061 as it's chemical make up is the closest to 5000 series AL which is what most tin boats are made of. Where to get AL? As JB said most big box stores stock 6061 but you can also look for local or online metal suppliers. A local may give a better price over the boxes and online may not be cost effective once shipping is added.

Most choose to work with the angle as it's most common and readily available however if you want something stronger AL extrusions can also be ordered in a myriad of shapes from online suppliers.

Frame it something like this


Google can give many ideas on how to frame it.

How to attach the frame to the boat? Make mounting brackets from short pieces of angle and rivet them to either the ribs or the hull. Anything (rivets, screws) through hull should be sealed the same way as show here for replacing rivets however you can also use 3m 5200 instead of epoxy as he did. I would personally use rivets(closed end blind/solid) as the SS screw method requires access to the backside for nutting which is not always the easiest.

 

[xmxaxrxtxyx]

Am also still figuring out exactly how to make a deck the best way. Am going in to town today and will try to find something that'll work. Thanks for the pic^

 

[jbcurt00]

The outer edges of the platform need support along the hull too, and possibly along the bottom on the rib to.

Once plywood is riveted to the aluminum, it'll all be remarkably firm and plenty strong.

 

[Watermann]

What size boat are you working on Jim? My SeaNymph had some pretty weak factory casting deck structure that I had to add too but there were cutouts for livewells and storage compartments that weakened the decking. What I did was to add I beams to act as pillars under the casting deck for support.

Yeah do not run screws through the hull into 2x4's and never use PT ply in an AL boat.

 

[gm280]

Jimmwaller, not only will aluminum be stronger, but also lighter then wood too. That would be my choice for your hull. JMHO!

 

[jimmwaller]

Thanks everyone for the replies so far!

I'm going to take your advice and do aluminum with rivets. Just one more quick question (for now! haha). I have used smaller hand rivets before, but never really riveted anything as large or as critical as a boat. Would you recommend a hand riveter or a pneumatic (or other powered) riveter? I already have a good air compressor so it won't be that expensive for me to add just the rivet gun. any recommendations for either a hand or air riveter?

Also, if I'm going to buy a riveter, I'm going to plan on re-riveting my jon boat since it's been needing it for a while. What size rivets do I need to be able to handle to re-rivet a hull? Would prefer to buy one nice riveter now that can do everything boat-related.

@truckdrivingfool: singling you out because this photo was incredibly helpful. So thanks! and, can I ask one question? Your 'vertical support' angle... looks like it's riveted at the top to the top bar, but how is it attached on the bottom to those bottom brackets? Or is it just resting on there?

Thanks all!

 

[Watermann]

I wouldn't recommend using blind rivets through the hull to hold a structural part that takes human weight. If one goes they all might and that could be a huge problem out on the water. Since you don't have the tools to buck solid rivets then I would use stainless machine screws and nyloc nuts with 5200 to seal them for anything through the hull holding up the deck.

So what is the boat we're all talking about anyway?

 

[jimmwaller]

Hi-
Thanks. I'm happy to buy the tools to buck solid rivets (wouldn't that just be a hammer and a bucking tool? Or is there like a pneumatic air hammer type gun tool that would be better?) if solid rivets are the way to go. As I was mentioning, I also have a jon boat that could use reriveting too, so I'd rather just buy whatever tools are needed now and then have them when I need them.

If machine screws are better, that's great and I'll use them. Really, I'm mostly interested in doing what will be the strongest even if there's an upfront investment in more tools. I've never once regretted buying a tool, and this one will definitely get used!


And: I'm so sorry! I thought I had put this in there earlier, but looking back I seem to have left it out. I wrote all that about the SPCN because I was planning to add that I couldn't tell what kind of boat it was from the title alone, which is all I have at the moment because the boat is parked at the storage lot... and I'm working pretty solidly until next sunday but I promise I'll post pictures then

Thanks

 

[Quick3201]

1/8' to 3/16 alum will support almost anyone. with decent sub frame like others show pror.