Tubes, How hard? - Page 2

ribit · 13 August 2007, 13:30

Some years back with a mate at the marine base he said the ribs were set between 2-2.5 psi in general, however I always had mine at around 3-3.5psi

Biggles · 13 August 2007, 14:30

Is their a nifty bit of kit that you can use that shows the pressure ?

Much like a car tyre pressure gauge.

JABS · 13 August 2007, 14:47

Yes, Ribcraft sell one!

£22.50 plus VAT plus postage!

Biggles · 13 August 2007, 16:00

JABS,

Cheers for that. Would probably be worth in investing in one. Would take the guess work out of tube pressures.

NR.

BigFella · 13 August 2007, 16:04

not sure, but this may fit the bill? I spotted it the other day whilst nosing around, a little cheaper too.

http://www.rib-shop.com/product.asp?P_ID=287

springtide66 · 13 August 2007, 16:10

Most tubes should be @ 2-3psi and are tested to 10psi

JABS · 13 August 2007, 16:20

Quote:

Originally Posted by BigFella

not sure, but this may fit the bill? I spotted it the other day whilst nosing around, a little cheaper too.

http://www.rib-shop.com/product.asp?P_ID=287

This looks like a good buy, BUT...

It is a 15 psi gauge. Working to 2 psi with an accuracy of 5% of full scale, which this could be, gives two plus or minus five percent of fifteen which is anywhere from 1.25 to 2.75 psi. This seems like a huge swing??

I guess the answer is to buy the gauge and 'suck it and see'!

Biggles · 13 August 2007, 16:30

I'll pop down to RIBSHOP and speak to Kieron and have a look at that bit of kit.

Regards NR.

BogMonster · 13 August 2007, 16:57

Quote:

Originally Posted by BigFella

not sure, but this may fit the bill? I spotted it the other day whilst nosing around, a little cheaper too.

http://www.rib-shop.com/product.asp?P_ID=287

Does it fit the Leafield type valves, or are the valves all the same fitting regardless of manufacturer?

codprawn · 13 August 2007, 17:08

You don't need guages - it's easy enough to tell by feel.......

JABS · 13 August 2007, 20:44

Quote:

Originally Posted by codprawn

You don't need guages - it's easy enough to tell by feel.......

I may not have my personal tube hardness tester with me..................

paul tilley · 13 August 2007, 20:46

i thought that all of the mod tubes marines included had working pressure 1.5psi max pressure 2psi printed on them

codprawn · 14 August 2007, 00:20

Quote:

Originally Posted by JABS

I may not have my personal tube hardness tester with me..................

Simple - kneel on the tube - if your knee makes a big dent it's too soft!!!

Apherel · 14 August 2007, 01:43

The leafield A6 pressure relief values hold pressure up to 2.4 PSI. I presume these were set at a point to suit most tube operating and safety needs?

My current tubes (hypalon) are rated to max 0.2 bar which is 2.9 PSI.

pathalla · 14 August 2007, 02:38

my tube is usually fairly hard in the morning so I have yet to check the pressure...

paul tilley · 14 August 2007, 06:21

leafield A6 &A10 have a range from 0.73 psi to 4.98psi with an upper limit of10.54psi for the A3 valve . it depends what pressure valve is fitted to your tube . we normally use orange spring 3.25psi relief pressure

Apherel · 14 August 2007, 06:50

Quote:

Originally Posted by paul tilley

leafield A6 &A10 have a range from 0.73 psi to 4.98psi with an upper limit of10.54psi for the A3 valve . it depends what pressure valve is fitted to your tube . we normally use orange spring 3.25psi relief pressure

There you go, the dangers of a quick google. Thanks Paul for the clarification. So can we come up with a rule of thumb? My effort... (a bit of care but no responsibility)

- codders knee test if you've got no equipment (pump it up until you can't make a dint in the tube) or
- a pressure gauge set to something your tube manufacturer recommends, or 1.5 to follow the Tilley guideline or between, say 2-2.5 if no other information or
-a pressure gauge set to 2-5 - 3.5 if you like it hard or a mate advised otherwise and
-a hand on your tube while you sort it all out

That should cover the bases!

codprawn · 14 August 2007, 10:51

Remember on a RIB tube pressure isn't as crucial as it is on a SIB. As long as the tubes are hard enough not to flop around unneccessarily then you will be ok - too hard and they are more liable to burst on impact etc.

Because of this and because I have great tubes made by Tilley with pressure relief valves fitted I am not really that bothered by tube pressure. As long as they "feel" ok then they are fine. Only had to put air in them once in the last year - obviously it had vented off last summer and by the winter they were definitely a bit saggy........