Flotation calculation question

Ed L.

Ed L.

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I've been to the USCG site but not finding what I'm looking for. I'm wanting to build a floating duck blind for mobility. The blind will be made using capped 8"x10' plastic sewer pipes filled with styrofoam packing peanuts. The floor will be 6'x10' using 1x 10's with a 3/8" or 1/2" deck. I'm thinking two guys and gear (500lbs) dog (100lbs). The blind will be 1/2 PVC covered with fabric and broken up with grass from around the pond. Total weight approx. 850lbs. How many logs will I need to float. This is on a sheltered area but needs to be removed after the season so permanent blind is out of the question. Anyone?

Thanks,

Ed L.


float_blind (600 x 450).jpg
 
Ed

Each one of those pipes will displace approx 215 pounds. You might want to use larger dia. pipe for more displacement and greater stability. The wider the flotation the more stable. Think pontoon boat.

62*10*Pi(1/3)^2
 
Aren't the newer packing peanuts biodegradable now? I don't think that is what I want to have as floatation. Also with all the pore space around the peanuts you won't be getting much floation if they fill with water.

Wouldn't salvaged (free) plastic drums be cheaper than the pipe?
 
Yep. A 55 gal. drum will support somewhere around 230 lbs half sunk and require no floatation foam. However, they are 22 inches in diameter, and, so half sunk would be 12 inches of bright blue above the waterline. I think I paid $11 a piece for mine. Still floating 2+ years.

Ed.

Check out my Barrel Barge.
 
Ed,

Be advised that there are two grades of pvc pipe, pvc and cpvc. I can't remember which is is is which right now but one of them is thicker wall and less flexible. You also might consider upping to 3/4 inch dia.

I helped make a turkey blind for for a friend using 1/2 inch and it worked ok but he only had light weight fabric hanging from the frame. You get grass on top of the fabric then add some rain water, ice, snow, etc, you may be unhappy when you arrive one morning.
 
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Ed , You might want to consider sch 40 pvc drain pipe with end caps. No need for peanuts. The other pipe is too thin walled and will crack. I would think a min of 4 pipes and the platform width of at eight ft. for stability. Outside pipes to out side of blind.

For the blind sides min of one inch pipe, preferred, inch and one quarter.

You can contact a local plumber and he can order the pipe for you. Some wholesalers won't sell unless you have an account.

Good luck on you projeck
 
Get a few Dow floatation billets. I made my 8x24 floating dock out of them and it stays in the water year round...and we get ice about 16" thick. They are probably cheaper than big pvc right now and give a lot more lift.
 
I second the sch 40 PVC with end caps glued on, If it holds water in the pipe then it surely will keep it out. Also if bought from a wholesaler or local plumber will be reasonably priced. The only time you may have to worry about it is in the cold, when removing your blind. PVC in cold weather is very brittle, and a glance off a stump or rock may shatter it. But you'll be towin it home anyway and it won't sink if one or two break. There is no way I'd use sch 34 (I think thats what the thin wall stuff is) I have shattered that in 45 degree weather tamping next to the pipe with a 4' level.
Also this is a great idea, and now you've got me thinking about building one. Keep us posted.
 
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Lee,

I did kick that idea around since I can get them locally but the boss put the kaboshes to that when I told her I needed (4) 24 x 48" blocks for flotation for me duck blind and they are $100 a piece.

Ed
 
Rick,

My boat was NO where near the size of a bread box. You know how cheap I am! Do you know how much Balsa cost these days...cheesh!!

Most guys around here are shelling out an old fiberglass tri-hull to build floating blinds and hiring a guy in town with an airboat to haul them out to the islands. I can't deal with that hunting by myself. I think this will work where I have to tot them across the islands and assemble at the blind site. Time will tell. I have a canoe cart I'm hoping I can use to get the needed parts to where I want to hunt.

Ed
 
No,no,no..the DOW styrofoam billets. They are 10" x 8' and are less than 50 bucks each...last time I checked. Look here;


http://www.dow.com/styrofoam/na/res-canada/projects/floating_rafts.htm
 
Andy,

I'm still in the planning stages and have a fishing trip coming up in about a week but as I get started I'll post pictures. If you beat me to it, I'll want to see your also.

Ed
 
Ed, call a lumberyard to see if they can get them..a marina will charge an arm and a left teste for them. Another thought would be to get 2 sheets of 2" Dow 150 or greater compression(which is the same material, I get 27bucks a sheet) and cut it into 12" strips..glue or band them together to give yourself two logs, 8"x12"x96". You can band a 2x to the top of them for fastening your deck which could be held on with a couple L brackets.
 
In the beginning I bought some 2" foam sheets that are blue in color. It has a scribe about every 12" for even cutting down the length. Is that what your talking about? Initially I was going to try this by gluing them together with 3m 77 spray adhesive but someone told me not to waste my time. Then I decided to place them inside the pipe but someone else suggested the packing peanuts that I could get the the pipes filled at the local fedex office and it wouldn't cost much. Then someone said the packing peanuts were bio-degradable. Now I'm back to the 2" blue foam!!!! Maybe what I'll do is put a 2x4 top and bottom and wire tie together. Then I could attach my floor deck with drywall screws and eleminate any fancy angles or brackets. What do you think?
 
Just for giggles, I'd do a recon trip on you nearest local waterway. I'm always amazed at the flotsam and jetsam on large waterways - those dock billets seem to crop up a fair amount.

I'd be worried about the thing flipping, not sure why, but it seems like a potentially top heavy operation.

I also like the PVC pipe idea. If you need super duper heavy duty stuff, that green sewer type line (I have some outside now, IPEX Ring-Tite 4" PVC) is pretty stout stiff. You can get it in larger diameters too, plus ring-tite makes caps for it.

Charlie
 
SOME peanuts are instantly degradable upon contact with water.....this type is made from spun corn syrup and "melts" on contact with moisture.....the really flushable part of this fact is that John Ratzenberger, who played Cliff Claven the know it all Postal Worker on Cheers, is the guy who came up with the idea--he's very GREEN, (and likely thats just a ploy to take all our guns away)....

Other Peanuts, the type that you'll get heavily overrcharged for at either the UPS or Fed-Ex stores, are still the same old non-biodegrable styrafoam that would be useable as floatation....

They are easy to tell apart..the biodegradable ones lokk lis that bleached out goose turd in shape....I'll assume that you haven't been living in a Third World Country for the last 50 years and will know how to fasten an Airline seat belt, and will also know what a styrafoam packing peanut looks like.....

Good luck on the project....

Steve
 
Holy Crap Charlie....A 10" dia pipe has .30 wall thickness and it gasketed! I'm afraid I couldn't afford this for my house let alone my duck blind. Thanks for the link though. You never know when I'll be asked to do a house plan. I always like having good info to offer.

Your right about the stuff floating around the river although most of what I find isn't usually re-usable

Ed L.
 
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