Pontoon problem .... straps snapped after winter freeze.

[Refueler]

One of my pontoons is made up from blue 200L plastic barrels strapped in two lines of 4 under a wood frame / decking. Its a commercial design produced by Jelgava Yacht Club ...

They were adamant that winter and ice would be no problem ... first winter - I pulled it up the bank ... but previous and this last winter I left in ... and those plastic straps have snapped ... barrels still under decking of course as frame holds them in ....

I now have to look at having the pontoon lifted and turned over so I can re-strap the barrels. It will actually give me opportunity to add more barrels as I want to put my self powered mini excavator on it to dig the channel ..

The pontoon as is can take the weight ok ... excavator is 450kg .... but I need to make all stable as the bucket / arm works.

Question is what is better than that plastic strapping ... its basically same as whats used to strap up large boxes / parcels ...

 

[jbweston]

I suppose webbing like that on lifejacket straps or as used to tie down liferaft cannisters might be better. But does it depend on what it is that caused the thinner ones to snap?

 

[jamie N]

Woven Webbing.

 

[Rappey]

Stainless banding ?

 

[Refueler]

I'd like stainless of course - but it needs to be something I can do DIY on the bank-side.

Woven webbing is my thought at present - but how long will it survive before rotting ??

But does it depend on what it is that caused the thinner ones to snap?

The ice in my channel forms to anywhere from 40cm to 1m thick depending on how severe the winter ...

Here's example of its power :

 

[AntarcticPilot]

Banding can be done in-situ, you just need a banding tool. I wouldn't be surprised if you can borrow one from a local company that uses it for heavy duty packaging. This kind of thing: Steel strapping tools & equipment

But I'd imagine that with your contacts you can find one you can borrow.

I've used them packaging heavy equipment for shipping to the Arctic. They're very common.

 

[Refueler]

Banding can be done in-situ, you just need a banding tool. I wouldn't be surprised if you can borrow one from a local company that uses it for heavy duty packaging. This kind of thing: Steel strapping tools & equipment

But I'd imagine that with your contacts you can find one you can borrow.

I've used them packaging heavy equipment for shipping to the Arctic. They're very common.

I'm off for a Model Flying meeting tomorrow all day .... then plan to talk to 'contacts' .... one in particular may be able to provide something similar as they bind industrial metalworks etc.

The pontoon will need to be turned over though with barrels uppermost so I can get to the underframe.

 

[AngusMcDoon]

Woven webbing is my thought at present - but how long will it survive before rotting ??

Polyester 5 years. Polypropylene maybe only 1. If you use woven webbing spending the extra on polyester is worth it. Some of JamieN's examples above are polypropylene. It's the same stuff that cheap lorry driver's blue rope is made from. If you get polyester webbing look for it in white as it's the most UV resistant.

 

[AntarcticPilot]

I'm off for a Model Flying meeting tomorrow all day .... then plan to talk to 'contacts' .... one in particular may be able to provide something similar as they bind industrial metalworks etc.

The pontoon will need to be turned over though with barrels uppermost so I can get to the underframe.

Of course, you'll also need a supply of stainless banding and clips. The usual stuff is steel, so it might be harder to "borrow" something suitable for use underwater. But it looks like you need enough for it to be worth buying a reel.

I'd experiment a bit before using it on the barrels; it's very easy to put a lot of tension on the band, and you could easily crush or cut into a plastic barrel.

 

[veshengro]

A trip to the local Car Breakers will provide you with lots of tough long lasting seat belts. Cheap, all you have to do is get amongst the wrecks with a sharp knife

 

[Boathook]

Stainless banding ?

I was thinking of steel banding. Should be a DIY doable thing as long as there is a suitable vice and club hammer, etc.

 

[MontyMariner]

Got any old rigging wire laying around?
Two or three strands could be used as bands.

 

[vas]

it is fresh water, right? so mild steel would work. I'd be more concerned on moving under stress and metal cutting through the plastic barrel on next ice season...

 

[penberth3]

Of course, you'll also need a supply of stainless banding and clips. The usual stuff is steel, so it might be harder to "borrow" something suitable for use underwater. But it looks like you need enough for it to be worth buying a reel.

I'd experiment a bit before using it on the barrels; it's very easy to put a lot of tension on the band, and you could easily crush or cut into a plastic barrel.

ISTR stainless band is available for this system, in fact I can't remember seeing anything else, e.g. galvanised, but that must be an option.

I guess the original failed due to shrinkage in cold temperatures? So whatever your replacement is, it shouldn't be as tight as possible, there should be some allowance for expansion/contraction.

 

[William_H]

Love all the photos as always. Looks a bit cold to me.
Stainless steel banding would be excellent except a real contradiction to the relatively soft plastic barrels. How did the plastic of the barrels cope with ice damage?
As said seat belt webbing from a car breakers yard might serve well with a wide area of pressure on the barrels. How to join p the ends of the webbing might be a question.
Suggestions. Sew a loop in each end and lash together under tension with multiple turns of light rope. Or sew a SS loop into one end to make a 2 purchase and sew 50mm velcro on to the webbing where strap comes back on itself. Large area off velcro can be very strong. I used to be into SCUBA diving. Tank slipping was a real problem. I put a strap of webbing around the tank. Each end of the webbing was folded back and sewn. I slipped a piece of brass rod inside each loop. I drilled one piece on each end and tapped a thread into matching point on the other piece. Screws through one rod into the other to pull them together. Holes were cut (melted) through webbing for the screws to go through. Tightening the screws got enormous prssure on the webbing. A bit tricky to get webbing lengths right. Perhaps not so successful over 2 metres of webbing with stretch.
Re stabilising pontoon with excavator on operating over the side. The best arrangement would be p[osts extending down to the bottom. Need to be able to be jacked down with some pressure. Or at least long poles sliding through a mounted tube. Ideally attached to the existing stabiliser arms of the excavator. I am not sure I would want to risk the digger sliding off the pontoon if relying on the buoyancy of the pontoon. Sounds like a fun challenge but be careful. ol'will

 

[zoidberg]

You might consider using dyneema rope in loops to make up your slings/bands, and galv fencing/rigging screws to achieve the needed tension. I'm aware of an individual who can supply e.g. 100m of 8mm dyneema for £100..... or longer lengths. Polysteel - which may be available locally and cheaply - used in similar loops would also suffice.

 

[Refueler]

Tks to everyone for ideas ... all appreciated.

I can get plenty of webbing here - we have an old Soviet style 'shop' that sells webbing for slings in any length you want ... with 8 barrels at pontoon now - 3 loops per barrel ... that's about 50m roughly (need to calculate). Plus another 5 barrels I have extra ... so overall about 100m !!

Rope / wire - is IMHO not such a good idea as its a narrow friction area to the barrel .. webbing or steel strapping spreads the contact area.

Today I am finally some time to go model flying ... been a while ... then once shops open again - I will be going to have a look ... and order the truck with lifter to lift pontoon and turn it over ...

 

[rogerthebodger]

I have looked at this before and used strips conveyor belting to hold plastic barrels on to my floating jetty

Ok we don't get your level of cold but it would still work.

I have also seen conveyor belting for the hinges where pontoons join and allow then to move up and down in tidal waters

Worn out conveyor belting can also be used if available locally

These guys local to you could help

Home

 

[Martin_J]

Looking at the conveyor fabric picture above reminded me of old fire hose..

Maybe some DIY clamps to hold to the pontoon and it's already UV and chemical resistant!

 

[andsarkit]

ISTR stainless band is available for this system, in fact I can't remember seeing anything else, e.g. galvanised, but that must be an option.

I guess the original failed due to shrinkage in cold temperatures? So whatever your replacement is, it shouldn't be as tight as possible, there should be some allowance for expansion/contraction.
View attachment 174821

The company I worked for used a lot of strapping for underwater sensors and loggers.
The usual options were either the above tool with titanium banding from Band-It or a reinforced plastic serrated band called Smart Band. If you have an contacts in the subsea world you might be able to borrow the tooling but the banding was very good if a little expensive.
Smart Band comes in various widths and materials