Hull questions

[Tracey Gilston]

If you buy a hull only or a sail away, how do they test for water tightness if not been in the water?? Or do they have to test it in water before selling??

[NB Lola]

I guess, only guess, they put water into it and look for leaks or they trust the welder, good question though

[Chewbacka]

I bought a sailaway and it was not leak tested by the hull builder, it was delivered by truck to the waterway and put in the water.  The crane operator said to have a good look inside for leaks before he removed the lifting straps.  I guess they rely on decent welders.

But 6 years on and the bilge is still dry, so it did not leak, even a little bit.  Had it leaked it would have been lifted out....................

[Tracey Gilston]

Thanks , We were thinking of fitting out ourselves, so suppose it needs to be tested first. Thought the welders/hull builders would have Some way of testing

11 minutes ago, NB Lola said:

I guess, only guess, they put water into it and look for leaks or they trust the welder, good question though

Yes we thought that perhaps??

[system 4-50]

My builder said the hull was tested before going in the water, but I can't remember how. Some sort of dye???

[ditchcrawler]

Dye Pen They spray a kind of paint on the weld and then a dye, if the weld is cracked the dye creeps through https://en.wikipedia.org/wiki/Dye_penetrant_inspection

[dmr]

I have heard that some builders fill the hull full of water in their workshop then look for water leaking out.

...................Dave

[Tracey Gilston]

3 minutes ago, ditchcrawler said:

Dye Pen They spray a kind of paint on the weld and then a dye, if the weld is cracked the dye creeps through https://en.wikipedia.org/wiki/Dye_penetrant_inspection

Ahh great , knew they must had a way if not able to put in water- thanks  

[reg]

Also worth doing a visual inspection of the welds on delivery, not difficult as the main one to check is the base plate weld and any others below waterline, of which there are few.

Although this might only really be practical for the external welds it does give an an additional level of checks.

[sharpness]

4 hours ago, Chewbacka said:

I bought a sailaway and it was not leak tested by the hull builder, it was delivered by truck to the waterway and put in the water.  The crane operator said to have a good look inside for leaks before he removed the lifting straps.  I guess they rely on decent welders.

But 6 years on and the bilge is still dry, so it did not leak, even a little bit.  Had it leaked it would have been lifted out....................

Exactly the same here.

[system 4-50]

The purpose of testing, any testing, is to prove that there are no faults. If a fault is found then the whole of the work is slightly suspect. If many faults are found then none of the work can be trusted, not even the bits that did not reveal a fault.  The primary purpose of testing is NOT to find the faults and fix them.

(one of my favourite rants)

[koukouvagia]

18 hours ago, dmr said:

I have heard that some builders fill the hull full of water in their workshop then look for water leaking out.

This is what we did when the new baseplate was fitted to Owl.  It was reassuring to know that there were no leaks before it went back into the water.

 

Edited February 4, 2018 by koukouvagia

[Tracey Gilston]

Thanks, thats good! Thought they must test somehow