How important is foam density?

[TheBuzzard]

Didn't read the crap. Put a retriever on it and make sure you know where it's at when it sinks. Pool noodles and foam ain't going to save it. Lost my badass freak and would have lost my fvpro without a retriever. TNT floated my fvpro up from 42ft in Davey Jones locker after 6 hrs of running knuckleheads away from the buoy.

 

[Roseand]

Doubtful. When riding a high hp short hull am hull with expensive drive train. Or if you like riding. Keep in mind poop can fail at any time. Usually the worst. Always have a way out. Dont be far enough away from shore or a friend you can't bail out. If you do. That's your fault.

So are you implying trying to get a short hull to float is a waste of time? I thought the xfr was a short hull?

 

[Roseand]

Didn't read the crap. Put a retriever on it and make sure you know where it's at when it sinks. Pool noodles and foam ain't going to save it. Lost my badass freak and would have lost my fvpro without a retriever. TNT floated my fvpro up from 42ft in Davey Jones locker after 6 hrs of running knuckleheads away from the buoy.

Do they still make 100ft retrievers?

 

[Sparkplug]

So are you implying trying to get a short hull to float is a waste of time? I thought the xfr was a short hull?

No. The xfr floats (bobs) just below the surface with foam. Not sure if it would with the dasa, as it's about 10 pounds heavier. But I bet it would.

If it has no foam. Your asking for trouble imo. Coming from someone who rides a Stand-up on the sac river 200+ days od the year.

 

[Quinc]

Do they still make 100ft retrievers?

bunch of options on amazon.

 

[Roseand]

bunch of options on amazon.
View attachment 439192

Here's the ticket, strong enough to be able to pull the ski up from. Just have to find an anchor point for the bag

 

[Quinc]

Here's the ticket, strong enough to be able to pull the ski up from. Just have to find an anchor point for the bag

I have something similar. Just haven't figured out the best way to attach it yet.

 

[bkspeedwerks]

I have something similar. Just haven't figured out the best way to attach it yet.

I have seen them attached to the foothold bracket and the bag velcroed in the foothold pocket

 

[Jhucke]

Figure out your available volume and get the density of the foam you intend to use. From there you can estimate if it will or how quickly it will sink. F=pgV

Yamaha had this just right on the superjet, when that goes down, the tail just barely bobs above the surface, but it is enough.

 

[WFO Speedracer]

someone should come up with an self inflatable bag system that is hidden somewhere like the handlepole pad or maybe under the rub rails , not sure how you would engage it though, you would need some foolproof way of not setting it off unless the ski sank..

 

[yamanube]

Figure out your available volume and get the density of the foam you intend to use. From there you can estimate if it will or how quickly it will sink. F=pgV

Yamaha had this just right on the superjet, when that goes down, the tail just barely bobs above the surface, but it is enough.

I think this is a USCG requirement for hull displacement to vehicle weight. That is how the SXR15 got so large.

 

[kevbo]

I think this is a USCG requirement for hull displacement to vehicle weight. That is how the SXR15 got so large.

If you are not worried about looking cool, make a custom jacket that can be easily zipped over the pole. A good upholster may be able to make it stylish.

 

[Quinc]

someone should come up with an self inflatable bag system that is hidden somewhere like the handlepole pad or maybe under the rub rails , not sure how you would engage it though, you would need some foolproof way of not setting it off unless the ski sank..

Surfriding - Avoid sinking and loosing the ski! Brainstorm...

Just got myself a new toy, rickter edge fr with a 950 dasa and needless to say, im scared poopless of sinking it. Apart from keeping it it wellmaintained ive been thinking what other safety precautions (and no scuppers) can be made in case one day im outta luck. So lets say poop hits the fan...

www.x-h2o.com

 

[Sparkplug]

I'm just wondering how many jet skis that have sunk and been saved by foam Vs hand tossed bags with lines.

 

[TheBuzzard]

But does an short a/m hull have room to hold enough foam to keep it from sinking? Let’s say, a Rip, Circus, or Bun size

According to lying sack of crap WDK guy, he said ages ago that tiny hulls can't hold enough foam to keep it afloat. That's why he didn't bother with foam and had open bulkhead.

 

[yamanube]

According to lying sack of crap WDK guy, he said ages ago that tiny hulls can't hold enough foam to keep it afloat. That's why he didn't bother with foam and had open bulkhead.

The theory makes sense, if a SJ just barely floats, anything with less volume and roughly all the same components isn't going to. If the hull is in any way smaller than a SJ, the math doesn't work out.

 

[Pro-pulsion]

I did the math on it years ago when I used pool noodles and I think it came out to needing 37 feet of pool noodles to maintain positive buoyancy for a 350 lb ski. I couldn't stuff that much into it but I know I was really close. It might be in my build thread too about the math part. I took the hole down the center of the noodle into consideration too which made for so much more material than I could stuff in. If they were all foam with no center missing it would have reduced the requirement by quite a lot and maybe would have all fit in. As Quinc said, they will soak up some and deteriorate over time, but I spoke to boat builder and he said the coast guard boats he has worked on have bags of them vacuum sealed under the main decks up here. He said as long as they stay dry they're incredibly buoyant.

 

[WFO Speedracer]

I have noticed on a lot of Seadoos I worked on that the foam is also seaed in plastic bags , one would suppose for the same reason, the foam they use absorbs water or at least has the potential to..

 

[Storbeck]

I think people underestimate how much foam it would take to float the ski if it is really only relying on the foam. Easy way to visualize it is all of the volume that is displaced when the ski is floating, you have to displace that much water to float the ski. Aftermarket skis don't have that much volume available in the tray area to have enough foam to float, I think the WDK guy is right about that. The way that they remain bobbing even when partially sunk is because there are all kinds of little nooks and crannies that can trap a little bit of air here and there. The fuel tank, the exhaust, inside the motor, little spots in the hull that air gets trapped, that is what saves you. I think that does not make the foam useless though, because the more floatation you have the more you DON'T have to rely on getting lucky with those little bits of air here and there, and also it slows down the water getting in so it buys you time. For those talking about skis that JUUUUST barely float, keep in mind what is the difference in buoyancy of a full fuel tank vs an empty one? A gallon of gasoline weighs about six pounds, so a gallon of gasoline has about 2lbs of buoyancy, where a gallon of empty fuel tank (air) has about 8 pounds of buoyancy.

 

[Sparkplug]

Plastic water bottles would be the absolute best thing. They are damn near indestructible, are incredibly light weight, conform to shapes. And nothing is more buoyant than air, besides other gases.

Just as methed up as stuffing a bunch of pool noodles places.