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  • #3842
    Anonymous
    Inactive

    Where should I look for the parts to make up a pressure measuring kit as described in the Wayfarer at the end of Chapter 1?

    The kit looks extremely simple, and I imagine the bits are the sort of thing you could quite easily from a home brewing shop, or a school chemistry lab.

    Unfortunately I don’t know where there is a home brewing shop (do they still exist?) and I don’t have access to a school chemistry lab.

    Any suggestions?

    Regards

    Richard

    #7598
    Swiebertje
    Participant

    Try a garden center or an aquarium shop. They tend to have hose and T-connectors. Or else a hardware shop may be able to help.

    All you need is some clear plastic hose, the same size as a garden hose. (Small hoses have a capillary effect that prevents proper measurement). A T- or Y-connector. And a small board where you fix the U-part of the hose to and that has a zero marker (line) and the upper and lower markers painted on them. Mine has two parallel pieces that allow me to shift the board over the U-part of the hose to zero the device. (If it is permanently fixed you need to ad and remove water until it shows zero). The boar also has some string that allows me to hang it vertically. At the end of the hose I used self vulcanizing tape to create a plug that (more or less) fits a Wayfarer bung.

    For me it was a matter of looking in my garage and improvise with what was there, in my pile of old junk.

    #7602
    Anonymous
    Inactive

    Thanks Swiebertje.

    For some reason I was unable to see that the clear plastic hose that has been used to set up our garden pond is a good clue as to where to look!

    While I was thinking about all this, it occured to me that you need to increase (or decrease) the pressure in the buoyancy chamber by some means (for example vacuum cleaner, says The Book) and then stop.

    That seems less than obvious.

    Will it work to just whip the vacuum cleaner hose away and shove in a bung? Can you do that quickly enough to retain 125 mm of over pressure in the chamber?

    If not, how else do you seal the chamber?

    Regards

    Richard

    #7603
    BluTak
    Participant

    If you’re looking for leaks get a vacuum cleaner that blows or a lilo inflator and hold it about an inch away from the bung. (don’t push it up tight or you will blow up the tank – you are just trying to increase the pressure inside slightly) Get a mixture of washing up liquid (10%inc) + water and paint it around all the joins including the keel band and rudder fittings. Any leaks will be obvious as bubbles will form. The bubbles will be obvious as they blow up and pop. You will probably find the hatch covers leak!
    Robert

    #7611
    Swiebertje
    Participant

    Vacuum cleaner? Why not do as I do and blow it with your mouth?

    The test needs very little pressure and if there are no leaks it takes just a few blows to get the required pressure in the tank. You will need to keep the measurement part closed with your thumb while blowing to prevent the water from escaping. Then put your tongue in the blowing tube and release your thumb to see if sufficient pressure has been build. Once the water reaches the upper and lower lines double fold the blow tube of the device and hold it firm and start timing.

    My board has five lines, the zero pressure line, the start pressure lines (top and bottom) and two end pressure lines (top en bottom) I blow the tank until the water crosses the upper line (give it some time to settle). The timing starts when it crosses the top and bottom lines. It should then not cross the next set of lines within the measurement period.

    It is actually a pretty simple process (but hard to describe as I just found out đź‘ż ). I intend to take some pictures when the season starts and we all need to check our boot anyway. I think a picture is worth a thousand word in this case. I shall put the result on the WIT site.

    #7612
    Anonymous
    Inactive

    @Richard6402 wrote:

    Unfortunately I don’t know where there is a home brewing shop (do they still exist?) and I don’t have access to a school chemistry lab.

    Any suggestions?

    Try B&Q – I’ve been able to buy clear plastic tube, T-pieces etc there.

    Richard

    #7616
    krgough
    Participant

    Check out the photo on this website – No need even to buy a t-piece.

    http://www.parkstonewayfarers.org.uk/Images/Photo_4.jpg

    PS – I’ve not tried this yet but it’s on my list on pre-season stuff to worry about.

    regards

    Keith

    #7617
    Anonymous
    Inactive

    @kgough wrote:

    Check out the photo on this website – No need even to buy a t-piece.

    http://www.parkstonewayfarers.org.uk/Images/Photo_4.jpg

    You’ll need a T-piece if you only have a single bung in the tank, as is usually the case for the front tank of a Mk II!

    FWIW you can find more information about buoyancy tests on the Parkstone Wayfarer website: http://www.parkstonewayfarers.org.uk/BuoyancyTestingDry.html

    Richard

    #7618
    BluTak
    Participant

    I aologise – my vacuum cleaner method is for checking for large/many leaks. I have worked in a boat repair shop where we used it all the time for checking/repairing tanks – some with quite large leaks. Its very handy if you’re on your own and you can take your time finding the source of the leaks – not always obvious. If you do find a leak, dry the tank well before fibreglassing/epoxying.
    Robert

    #7619
    krgough
    Participant

    @Richard Readings wrote:

    You’ll need a T-piece if you only have a single bung in the tank, as is usually the case for the front tank of a Mk II!

    Ah-ha very true – thanks Richard

    #7621
    Anonymous
    Inactive

    Thank you all very much. The picture makes it all so clear – and I had not worked out what you did with the t-piece, but now I understand (I think …).

    #7755
    Anonymous
    Inactive

    I found my local hardware shop had the transparent hose – hidden in an alcove!

    A few minutes investigation without even making up the pressure gauge, just blowing into a bung hole, identified a leak.

    Whizzo, thank you.

    #7761
    krgough
    Participant

    Hi Richard,

    I’m in the process of doing the same. It’s proving a bit of a nightmare trying to get a seal. The hatch leaks (it’s the small inspection hatch type not full size) which I think can be easily sealed with some mastic, but it seems there is some damage under the side deck next to the transom, right in the most inaccessible corner – I have no idea how it could get damaged there?

    regards

    Keith

    #7763
    Colin Parkstone
    Participant

    Your damage under the side deck is possibly the joint between the back tank and the transom.
    This is not that unusual and can be got at from inside the aft tank if you have the large hatch and works well with the boat upside down.

    C P

    #7764
    Swiebertje
    Participant

    Another source of problems is the joint between the tank and the gunwale on a MK2 (I don’t know if this also happens on other marks). Newer boats have an aluminium strip and self threading screws. Despite the screws the joint will still start leak after some years.

    Though my solution will not win prizes (and probably earn some serious criticism from Colin) I have fixed this by squeezing some Sikaflex on my fingers and then, with my arm through the hatch, smear it inside the tank on the joint. Since nobody sees it I don’t care how it looks and I make sure there is enough of the stuff on the joint. I even try to push it in between the two layers with my fingers. Though intended as an emergency repair it has held remarkably well.

    BTW use white Sikaflex or be prepared to have black fingers for a week or so. Or maybe I should try surgeons gloves next time?

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