Floatation for small jetty/ pontoon. Suggestions please.

[JayInOz]

G'day peoples. I want to build a small floating jetty, maybe twenty feet long, anchored at one end to the bank of my farm dam. Just somewhere to sit and feed my fish without getting mud on my boots. I'd appreciate suggestions for flotation- and anything else you good folks might consider helpful. Thanks muchly. JayInOz

[PeterSibley]

A mate just built on and of course it was a beautiful job !

A mini catamaran ...2 ply hulls glass all over with a small deck between that a ramp runs down to .
His is in a river that floods on ocassion so the shape is relevant ,it's also set up to be set adrift and dragged up the bank if necessary .I'd guess your dam isn't that likely to flood or have a fast flow eh ?

The cheap and cheerful version is a cunning assemblage of those plastic 200 l drums with a deck over and hopefully covering them .

[purri]

I'd go cheap and cheerful and nut out what knots are best. (BTW no "Telecom rope")

[skuthorp]

They just sailed a boat made of plastic bottles across the Pacific, find a source?

[Oyvind Snibsoer]

The most common option in these parts is to use industrial plastic barrels. They come in various sizes, the most common for pontoons are approx 150 liters I believe. You should, of course, get some that have been used for water-soluble non-toxic chemicals, e.g. soap, weak acids or lye.

Dunno how it works around your place, but here companies have to pay almost $10/barrel to dump them, so they are more than happy if they are able to give a few away.

8 barrels should give sufficient floatation for your intended size. Get more if you can and partially fill them with water for a more stable platform.

[Mrleft8]

Mermaids.

[David W Pratt]

After reading this thread this am, I looked at some finger docks when I went out to the boat. They are supported by squarish, black plastic tanks made for the job. If you want I can go back and write down any info on them.
Good luck.

[gibetheridge]

It's in fresh water, no teredos, perhaps the most cheap and cheerfull would be a couple of logs with 2x6 planks nailed in place over a bit of diagonal bracing.

[PeterSibley]

Any logs from Jay's locality would sink like stones ....it's that Oz hardwood ,about 70 pound per cubic foot .

[JayInOz]

Thanks for the suggestions peoples! You're right Peter- none of my timber floats- I put about sixty pounds of air in a car tyre and attached it to a long iron bark sapling in order to run polypipe out into the dam from a pump- the tyre is supposed to float on the surface and keep the foot valve out of the mud- it sank like a stone.
I like the idea of mermaids but I'm worried they might eat my fish. And the missus would insist on real ugly ones.
Plastic barrels here are expensive and more to the point hard to find- everybody has problems with huge numbers of mice, so barrels are used for horse/dog/chook (chicken) feed etc., and for storing pasture seed.
Most folks seem to just drive some posts into the mud and have a permanent structure out over the water- and in the summer when the water level is waaay down, anyone sitting up there looks like a total dork I want to hand feed my fish and be able to get an up close look at 'em.
How effective would it be to make a couple of "barrels" from fibreglass? That way I could include brackets or timbers or something to attach the jetty to. Or maybe two long lengths of large diameter P.V.C. pipe? More thinkin needed JayInOz

[Bruce Hooke]

Around here, at least in areas where floating docks are reasonably common, it is pretty easy to get big fiberglass "logs" that are designed to provide flotation for docks. As I recall they are typically about 20cm x 75cm by 2.5 meters. They are not the cheapest thing going but they are not too expensive.

Logs, even logs from lighter trees, would be a bad idea because once soaked with water, even fairly light trees do not really have that much buoyancy and if you ever need to haul the dock out the logs are heavier than all get out.

[Phil Y]

You could maybe knock something up in ferro cement? But I'd hunt around for 200 litre plastic drums at a good price. The ones without removable lids might be more available than the ones with? or how about the squareish 20 litre chemical containers? Black ones are best for UV stability. If you can only get white maybe paint them and build the platform to ensure they are well shaded. You could check at the local tip, or a farm for those. Or a restaurant.

[Bruce Hooke]

How effective would it be to make a couple of "barrels" from fibreglass? That way I could include brackets or timbers or something to attach the jetty to. Or maybe two long lengths of large diameter P.V.C. pipe? More thinkin needed JayInOz

If you want to go the home-made route, rather than laying up all sorts of fiberglass I think what I would do is use pressure treated plywood and make sealed boxes. The corners could be made by screwing into 5cm square pieces of wood, with lots of 5200 or some such to seal the seams. For extra durability you could fiberglass the corners from the outside.

[Bruce Hooke]

or how about the squareish 20 litre chemical containers? Black ones are best for UV stability.

When getting used containers just be careful regarding the previous contents of the container...

[skuthorp]

240 ltr Olive and pickled onion barrels are imported full and are available in various places round Melb at a reasonable price. Ask one opf the big importers where their empty barrels go in NSW.

[gibetheridge]

A fishing camp up the coast a ways made a big float to use for fuel storage. The floats were 2 of those giant long propane tanks you see vertical at gas stations. Around here it's not hard to find 100lb propane tanks at the dump, for free. A few of those crosswise under a couple of long beams would last a long time, they're made with pretty thick steel. You could weld vertical plates to each tank for attaching the beams. They'd be easy to replace if ever necessary.

Disclaimer...Make sure to remove the valve and fill with water to overflowing before welding.

[PeterSibley]

240 ltr Olive and pickled onion barrels are imported full and are available in various places round Melb at a reasonable price. Ask one opf the big importers where their empty barrels go in NSW.

The cities are full of drum recyclers , the freight out to Jay's place would be pretty high though .Maybe next time you're in the smoke mate , pick up a ute load .The couple I have are 200 litres .

[JayInOz]

Next time I'm in the smoke Peter I'll be riding the Harley- draggin' empty drums would be so uncool The comment from Gibetheridge got me thinking- I don't think I've seen empty propane tanks at the tip for a while- but a lot of small cars have heavy duty, low profile, poly (or something similar) fuel tanks- maybe a couple of those would do the trick. Still thinkin' JayInOz

[Oyvind Snibsoer]

An option could be to use blocks of polystyrene. Around here, 10cm thick sheets are sold in packs of 6 for sub-floor insulation. Make an inverted crate around the stacks to keep them in place and prevent loose pieces to float away and pollute the lake.

[JayInOz]

Oyvind that's a great idea!! I love this place JayInOz

[gibetheridge]

If you use foam make sure it's closed cell. Some of them soak up water like a sponge.

[PeterSibley]

If you have a cold room builder close by Jay , he'd be a good source .I built a couple of pontoons out of foam and glass once ,it wasn't that cheap but they were good .The glass was essential as otherwise bits were getting knocked off all the time .

[Plumbtex]

How about old electric water heater tanks stripped of their outer skin and insulation. Plug all the holes and set them crosswise to your walkway. A good size plumbing shop will discard them by the dozens.

[PeterSibley]

How about old electric water heater tanks stripped of their outer skin and insulation. Plug all the holes and set them crosswise to your walkway. A good size plumbing shop will discard them by the dozens.

WE HAVE A WINNER ! WHAT A GREAT IDEA ! I've used a few old hotwater cylinders , one as a casing for a bronze melting furnace ,another for a biodiesel rig .I didn't think of them as pontoon floats ....well done .

The steel one them is about 1/8'' thick ,so they should last well in fresh water ,especially with a decent coat of paint or tar .

[paladin]

Remove the hot water first. Water inside the tank will weigh the same as water outside the tank.