Inflate Futura

[prairie tuber]

Originally Posted by Locozodiac

Seems that by mistake you have posted the over inflation valves issue reply on the wrong forum. Now, this is a new SIB forum, that I know none of the standard less pricy plywood/alum floor sibs comes with overinflation valves, unless you change/add them to sib's tubes.

Your RIB comment "They are seperate valves on my RIB" can be erroneously interpreted by SIB newbies as they will not know the difference between a standard valve (Halkey Roberts Type) and a overinflation valve. Imagine infllating a standard Sib with a tyre air compressor...Booom!!

Happy Sibbing

Standard Halkey Roberts valve above, pressure relief valve below. You can tell very easily if your SIB (or RIB) has pressure relief valves.

[John Kennett]

Originally Posted by prairie tuber

You can tell very easily if your SIB (or RIB) has pressure relief valves.

You'd think so, but Codprawn thinks that his Quicksilver inflatable has them . . .

John

[Poly]

Originally Posted by Locozodiac

...donw here haven't seen any gas station where you can inflate your car tyres having pressure gauges attached to the air hose, so erroneously concluded that everybody used hand gauges.

I think in the UK you will find it almost impossible to find a "gas station" compressor which doesn't have a gauge on the line (or a 'dial in' setting on the pump).

Can't compare cyclist tyres against sibs, cyclist tyres use between 50 to 100 PSI, huge pressure, very low air volume, Sibs/Ribs huge air volume, very low PSI. What gives more rigidity : Air volume + adecuate PSI.

I wasn't really comparing the cyclist in the same way you weren't comparing car drivers. I was saying serious cyclists will set the tyre pressure to the conditions, specific tyre, etc - but casual cyclists will do a "squeeze" test. The same applies to SIBS - for absolute optimal performance a manometer of some sort will make a difference - but for casual use a squeeze test will probably do.

[codprawn]

Originally Posted by John Kennett

You'd think so, but Codprawn thinks that his Quicksilver inflatable has them . . .

John

So would you tell me how it vents off if I put too much air in???

Unless I have some amazing sort of leak that only lets go at a certain pressure............

[John Kennett]

No idea. Sounds like it only functions up to a certain pressure, then starts to leak. I think that to describe that as "a pressure relief valve" is stretching the point a bit.

How does the pump blow off from the valve anyway? Isn't it a bayonet fitting?

[prairie tuber]

I don't know about the quicksilvers, but the main sponsons of zodiac sibs have a spring loaded outer ring (the 'navigation' ring whch also closes off the baffles) that surrounds the inflation valve. This spring tension is set so that it will compress and allow air to escape if the inflation pressure is excessive. The only problem with relying on this system is that if the seats of this valve are not kept lubed regularly those seats can stick and and not allow excessive air pressure to blow off.

[Locozodiac]

Originally Posted by Polwart

I was saying serious cyclists will set the tyre pressure to the conditions, specific tyre, etc - but casual cyclists will do a "squeeze" test. The same applies to SIBS - for absolute optimal performance a manometer of some sort will make a difference - but for casual use a squeeze test will probably do.

Polwart, you have the right answer : SERIOUS sibbers will set tyres/tubes to appropriate working pressures , CASUAL sibbers will do a squeeze test, or finger gauge test. That's the finality of Ribnet, ABC boating advise, lots of information available on all sib/rib related subjects, as John states, better than a magazine. I would have liked 12 years ago to have had all the information available now when as a complete newie bought my first sib. Must admit that have been using a gauge ever since with excellent sibbing performance on all my owned different brands water toys.

On previous posts, was forgetting about a very precise concept related to inflating to a correct working pressure, you can inflate your tubes to 3-3.4-3.5-3.6, or pressure you think it's the correct. But the idea is to have all tubes inflated to the same equal working pressure, although all tubes are air tight independent, all work as a compact unit, interacting together by means of internal cones to ballance better internal air pressure between tubes. Same pressure exactness on all tubes is only achieved by means of a gauge.

When a PVC sib is built at the factory, generally external cones, internal cones, tubes are hand glued/or thermo welded to form the sib tubes structure, if glued, after a 48 hours rest to glue well, it's inflated to 5 PSI for 48 hours, then soappy water tested to see if there is any air leak, if ok retainning good pressure, fine, if not, a precise search is done to find problem areas in valves, fabric to look for pores, seams areas, and corrected. Then the ok sib structure is defleted to it's working pressure on the final assembly line where rope ties, oars, drings and sib's botton fabric are glued. All this process is done in controled temperature rooms.

That's why is recommended in owners manual to inflate all chambers to 3.5 PSI (working pressure on water) to tight well both lateral side joinners to the tubes and have perfect aligned paralell floor sections one after the other & ridgid tramson area, as was originally built at the factory. Once on water if it has a bit more pressure, won't do any harm at all. So deflate a bit if this gives you mental peace of mind. Italy Gommonautica tests their RIB Hypalon fabric tubes to 10 PSI for 24 hours, before delivering their boats to final clients.

This post will end my personal concern about inflation procedures advises, so all will depend on what type of boater you want to be : Serious or Casual, it's entirely up to you.

Happy Sibbing

[codprawn]

Deflate a bit? I thought serious people had to be spot on?

How can you be that accurate when the pressure will vary so much depending on weather - direct sunlight - water temperature etc etc???

As long as you balance the pressures when inflating - not too much into each tube so as not to strain the baffles - then I think you will be fine. Doesn't seem to have ever harmed any SIBs I have seen.

[Locozodiac]

Originally Posted by codprawn

Deflate a bit? I thought serious people had to be spot on?

How can you be that accurate when the pressure will vary so much depending on weather - direct sunlight - water temperature etc etc???

As long as you balance the pressures when inflating - not too much into each tube so as not to strain the baffles - then I think you will be fine. Doesn't seem to have ever harmed any SIBs I have seen.

1-I'm a very proffessional 12 year old sibber user and 3 years seller, no need to deflate, always spot on & well sib water tunned.

2-Cannot state a exact inflation pressure chart for every country worldwide, as you have mentioned varies accordingly to sunlight/ no sunlight/different water temperatures,/environments, etc, so it would be a matter of trial & error to inflate any sib to achieve it's best working pressure to match the best particular country environment. If you are a sibber who likes to cary many buddys, full tank, accesories, using a max rated engine and like to full wot, then you should inflate your toy accordingly. If you like sibbing on marshmellow like tubes with poorly sib performance, it's entirely up to you.

3-So that other ribbers understands better this environment/air pressure issue, in my particular case (Peru) in plain summer with temperatures of about 25/28 Cº, usually inflate my sib in the morning under shade (have a garage) to 3.0 PSI, our water temperature is about 12/14º, the same sib at noon 12 o clock while heats up in plain sun on water, will end having near 3.5 PSI. In winter 15/17 Cº with no sun at all & cold water, inflate to 3.6 PSI/ 0.25 Bar and use all day long, there will be a slight tube deflation though, not a big issue that affects sib performance. Knowing my particular outside environment & water temp no need to check pressure once on water. These parameters work well for me in my particular country. May not applicate to other countries. I'm not a evironmental worldwide guru. This is not a exact science for any country, so be around +,- 3.5 PSI 0.25 BAR.

4-When inflating any sib/rib you always have to air balance all tubes, for the best tube baffle balance/compensation. inflate in a 360º sib tube go round inflation procedure with no more than 0.25 PSI between chambers untill correct working pressure is obtained. Forgot to mention on my last quote, that most reputed sib manufactures once the inflatable structure is ready, tests each tube separately one at a time with 4.0 PSI for hours to see if each baffle is correctly sealed between tubes, defleted and so on. If all tubes ok, this structure is inflated to 5 PSI for the overall final pressure test.

Bottom line: Make yourself a nice UK 4 seasons water temperature/chart on the base of trial & error, but first, buy yourself a nice hand gauge, if difficult to obtain, probably will send you one. For ending, please stop going round the sib again, again with this endless inflation temperature issues as you will always have another discomformity answer to post, generally not applicable worldwide.

Happyy Sibbing

[jyasaki]

Originally Posted by Locozodiac

But the idea is to have all tubes inflated to the same equal working pressure, although all tubes are air tight independent, all work as a compact unit, interacting together by means of internal cones to ballance better internal air pressure between tubes. Same pressure exactness on all tubes is only achieved by means of a gauge.

Hmm. Seems to me that if I pump up chamber A to, say 3.3 psi, and chamber B to 3.5, the baffle will tend to equalize pressure between the two.

Real world, if you performed that scenario, Chamber A would then read 3.5 as well (or close to it), as you would have reduced the volume by shifting the baffle into A by inflating B to a higher pressure.

But I agree, it's not as critical as this thread makes it sound. Pump it up and go. If it's too floppy, pump it up more. If it's too firm, well... hopefully nothing bad happens.


jky

[Locozodiac]

Originally Posted by jyasaki

Hmm. Seems to me that if I pump up chamber A to, say 3.3 psi, and chamber B to 3.5, the baffle will tend to equalize pressure between the two.


jky

Yes this is true, the ideal will be to add very little air into each chamber for the inner tubes baffles to remain neutral. So no tube equalizes the adjacent chamber, all working at their same pressure. it's just a pure technical concept, the overall idea of inflating all tubes at their best.

Happy Sibbing