foam core sneak box

[Doug H]

I'm Thinking of buildng a sneak box.
does anyone know of any foam core glassed boats?
It seems that using foam would be alot easier than wood.
also much cheaper.I know it's not the purest thing to do.
But vhey they have been building boats like that for 50 years
I'm just wondering if it is practical to do in a single wide garage

 

[Ray]

The foam used in foam core boat construction is really exspensive stuff and not the stuff you get from home depot. I have made one foamer as an experiment and though successful, it is not something I recommend. You do not save any weight since you have to use more epoxy and glass to protect it than you would for plywood. I stuck to the light and practical side of the epoxy situation and the boat didn't make it through the second season without major damage through miss handling by a borrower. The FG also delaminated from the foam in many spots due to air pressure changes and stress while being handled from the truck to the ponds. It did not save any weight and makes a huge mess to cleanup. At least saw dust is heavy enough to be swept up off the floor. Foam dust becomes static charged and gets every where. After 3 years I am still finding pockets of the little blue chips in the shop when ever I move something around.

If you are serious about this idea then go to Glen-L's website and read up on their tutorial for their foam core dingy. They sell the correct type of foam to use in boat construction. Plywood is cheaper.

 

[Bill Gass]

Doug, not sure what exact type of sneak box your looking at but I once saw a small boat made from three sheets of blue construction foam, fiberglassed over. And maybe some plywood to edge in the cockpit. Anyway it looked like a pretty unsinkable little craft and quite inexpensive. I'm still looking for the site, perhaps others on here might know. It was a home made website with lots of pics and instructions. If I can find it I will post it on here.

Bill G.

OK after some searching here is the link that i was refering to
http://www.diyduckboat.com/

This a smaller boat meant to be poled or perhaps a small motor.

Here is another one that is close in design
http://www.duckhuntingchat.com/viewtopic.php?t=63146

http://www.duckhuntingchat.com/viewtopic.php?t=68168&highlight=

Not sure of that is the type that you were looking for but they are neat little boats.
BG

 

[Ray]

Bill those are good links to the original Too Tall Neandertal method from Cafe Outdoors forum in MO. That was 4 of 5 years ago that he built the first one documented on the internet. Then that other guy started the diyduckboat site wanting to sell the plans which you do not need to buy if you are good with the search button.

Here is the construction of my duck monitor. Many viewers whined about the shape of it, but it was built for a very specific environment and it does really well in it. It would not work so well in other environments outside of a sedge marsh like ours. I have a problem with sit ups so I don't work well with the boat, but for anyone with no back issues and likes layout hunting this boat once grassed around the cockpit is a killer.

http://www.refugeforums.com/refuge/showthread.php?t=425261


And this is probably the most comprehensive documentation of a foamer build.
http://www.refugeforums.com/refuge/showthread.php?t=435143


However, none of these are sneakboats, just marsh boats. There is no deck or under deck storage in these. Traditional foam core is over a frame and then lots of fitting and sanding with huge amounts of fiberglass inside and out. You could take a sneakboat frame and foam core it and make a big heavy boat with all the fiberglass, but if you use the home depot foam it will pull apart since that stuff is not engineered for those kind of forces.

 

[Doug H]

Thanks for all the info. looks like i've got a lot of research to do.
To be honest it's mostly scarfing and beveling all those edges that i'm not
looking forward to. I figured I could use a utility knife on the edges instead
of planes and saws.

 

[Doug H]

Just looked at those sites. I was thinking of a barnegat bay sneak box for.well for barnegat bay and the delaware bay. I was thinking 3/8" closed cell sandwich construction using instead of wood on maybe Brant III plans.
whatever I use it will have very sea worthy the jersey shore and the del bay and river can get pretty sporty.

 

[Bob B]

Doug
Im not sure you would not be better served by a cackler or snow goose type hull if you really like the late season and are safety minded. The extra freeboard is a big plus if you blow the call on the weather.
I know the history is there with the barnegat but I think you would have a good bit of extra with the extra freeboard.
As for foam the Core Cell is the cats a$$ but is very expensive but will work with polyester resin. Balsa core is also an option. Cheaper and fine if you do not hole the skins and loose the seal.
I have spent many hours talking with my brother in law who works with epoxy for a living and he is fine with blue board as a core if you dont use polyester resin. Very cheap and easy to work but as stated messy, labor intensive to curf and not much lighter if you do not infuse the glass or use a wet out machine to control the epoxy to cloth ratio.
So with all materials going up in price wood is still the easy choice but the others work too esp if you have a friend in the boatbuilding biz who can get you some materials at cost. But you need a form to build on and that is not nec. with stich and glue ply.

 

[Ray]

To be honest it's mostly scarfing and beveling all those edges that i'm not
looking forward to. I figured I could use a utility knife on the edges instead
of planes and saws.

The scarfing and beveling of the edges of the plywood is a lot of work, but it is less than 5% of the total labor you will put into building the boat. A couple of hours to set up for the sander, hand plane, or skill saw method, and then a couple hours or less of work and you are down to epoxing the two pieces to gether.

And if the whole idea of scarfing puts you off that much you can put the joint at the back of the boat and use a but joint with a plywood patch on the inside. It will be stronger than the scarf joint, but will not bend at all, which is why it needs to be placed in the flattest part of the hull. The bottom two pieces would be in the back end and the sides more in the middle. Sand into the joint a little deeper than normal on the outside and fill with additional layers of epoxy and tape.

The other method is a half lap type joint than can be machined with a router. This could be harder to bend than a scarf joint, but it does get you the contact surface area you need for the strength.