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Fly Navy

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  • Please...............no tittering in the cheap seats, now:

 

I am told (by an ex- houdini hatch salesman) that Houdini hatch's are the quickest way to producing condensation inside a boat - ever!

Even faster than single glazed windows.

 

So...........

 

Thinking outside the box........

 

What if I fitted a suitably sized VELUX triplex (openable) window into the superstructure (ceiling)????/

 

No condensation and tough enough to walk on (closed of course!).

 

Tittering can commence together with any constructive comments please ?

Edited by Fly Navy
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We have a conventional houdini hatch; I cut some twin-walled plastic to fit and glued it to the metal frame of the opening window, so it opens with it. With the glass and plastic, and tape around it to stop airflow inside it, it is effectively triple-glazed so we get no condensation except from the fixed part of the metal frame.

 

3159128437_b59438ed2f_z.jpg

 

3159962210_f0c5472f15_z.jpg

 

3159961780_cdcc6d4622_z.jpg

 

 

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13 minutes ago, Fly Navy said:
  • Please...............no tittering in the cheap seats, now:

 

I am told (by an ex- houdini hatch salesman) that Houdini hatch's are the quickest way to producing condensation inside a boat - ever!

Even faster than single glazed windows.

 

So...........

 

Thinking outside the box........

 

What if I fitted a suitably sized VELUX triplex (openable) window into the superstructure (ceiling)????/

 

No condensation and tough enough to walk on (closed of course!).

 

Tittering can commence together with any constructive comments please ?

I had one on my widebeam. Worked well.

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6 minutes ago, Keeping Up said:

We have a conventional houdini hatch; I cut some twin-walled plastic to fit and glued it to the metal frame of the opening window, so it opens with it. With the glass and plastic, and tape around it to stop airflow inside it, it is effectively triple-glazed so we get no condensation except from the fixed part of the metal frame.

 

3159128437_b59438ed2f_z.jpg

 

3159962210_f0c5472f15_z.jpg

 

3159961780_cdcc6d4622_z.jpg

 

 

Can't help thinking that if the consumer has to bodge a solution it sort of shows that the product has a basic design flaw.

 

I sometimes end up bodging things that I purchase to get them to work properly, but it does irk me somewhat that the person paid to do it hasn't done their job and left it to me.

Edited by blackrose
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6 minutes ago, blackrose said:

Can't help thinking that if the consumer has to bodge a solution it sort of shows that the product has a basic design flaw.

It's a basic design flaw of all single-glazed windows that they aren't double-glazed!

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15 minutes ago, Keeping Up said:

It's a basic design flaw of all single-glazed windows that they aren't double-glazed!

Not really Allan. In terms of condensation, single glazed cabin windows will drip into the gutter running around the perimeter - a feature of most modern manufactured boat windows. You'll still get a bit from the frames assuming there is no thermal break but nothing like the quantities of condensation you'll get dripping into the boat from a single glazed horizonal Houdini hatch. That's why you've had to come up with your own solution for the hatch (which by the way is admirable), but probably not for your single glazed windows.

Edited by blackrose
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We have a couple of Bomar hatches on our boat and get next to no condensation on them.

 

http://pompanettellc.com/current-catalog/hatches/2000-series-high-pro-hatch/

 

Only on the very coldest of nights do we get a little moisture on the frames. But we make sure that our boat has plenty of ventilation at all times which is the key to avoiding excess amounts of condensation.

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Mmm. So it seems it's not such a silly idea after all, Watson??

 

I was also told by an "expert" that on a 60 foot NB, with the sun blazing down on one side and not the other, the side in sun - expands up to 1 inch. That's 2mm per foot length of boat that moves.

This causes cracks in grouting, tiles and above all else, is the main reason for double glazing units failing prematurely (blow).

 

Quell surprise.

 

FN

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51 minutes ago, Fly Navy said:

Mmm. So it seems it's not such a silly idea after all, Watson??

 

I was also told by an "expert" that on a 60 foot NB, with the sun blazing down on one side and not the other, the side in sun - expands up to 1 inch. That's 2mm per foot length of boat that moves.

This causes cracks in grouting, tiles and above all else, is the main reason for double glazing units failing prematurely (blow).

 

Quell surprise.

 

FN

Don't put any windows in it then. They wont fail that way.

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1 hour ago, Fly Navy said:

I was also told by an "expert" that on a 60 foot NB, with the sun blazing down on one side and not the other, the side in sun - expands up to 1 inch

He’s out by rather a large factor. The coefficient of expansion for Steel is around 12x10-6 per degree C. So a difference of temperature of 20C (unlikely I would have thought) gives 240x10-6, or 0.000240. Over 60ft that gives a difference in length of 0.0144ft, or 0.17”. 

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2 hours ago, Fly Navy said:

 and above all else, is the main reason for double glazing units failing prematurely (blow).

 

Since sealed double glazing units float within the window frame, I think it unlikely that expansion and contraction of the shell would be a significant factor.

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3 hours ago, Fly Navy said:

Mmm. So it seems it's not such a silly idea after all, Watson??

 

I was also told by an "expert" that on a 60 foot NB, with the sun blazing down on one side and not the other, the side in sun - expands up to 1 inch. That's 2mm per foot length of boat that moves.

This causes cracks in grouting, tiles and above all else, is the main reason for double glazing units failing prematurely (blow).

 

Quell surprise.

 

 I think your "expert" is feeding you 'Duff info" having worked on the SR 71 at Lockheeds Skunk Works Famous for it's dripping fuel tanks when standing  to be taken up at Mach3 'ish" granted it was titanium not steel & for the life of me can't remember the expansion rate"was some time ago " factors, the actual #'s were much nearer to the quote in post #11 If the figures from your source'were correct sunny day boating would be even more difficult( thinking lock width/boat beam ?)

 

Edited by X Alan W
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10 hours ago, WotEver said:

He’s out by rather a large factor. The coefficient of expansion for Steel is around 12x10-6 per degree C. So a difference of temperature of 20C (unlikely I would have thought) gives 240x10-6, or 0.000240. Over 60ft that gives a difference in length of 0.0144ft, or 0.17”. 

Our dark blue roof got to 65 deg C in the sun most days last summer. The side less so but maybe + 30 deg from the shaded side. 

Fried all or eggs on the roof. Saved on washing frying pans.

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3 Houdinis, condensation is bad but not on the glass but on the alloy frames particularly when it rains and the temperature drops a bit.

They need to be constantly just open on the catches to avoid it,.

I've told the wife to stop breathing as it makes it worse but will she listen?

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4 hours ago, Boater Sam said:

3 Houdinis, condensation is bad but not on the glass but on the alloy frames particularly when it rains and the temperature drops a bit.

They need to be constantly just open on the catches to avoid it,.

I've told the wife to stop breathing as it makes it worse but will she listen?

Ventilation is the key to reducing or omitting completely condensation.

 

We very rarely get condensation on board as we keep all of the windows and hatches cracked open when we are onboard. The only time we get condensation is if we forget to open a window or hatch. 

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10 minutes ago, Ex Brummie said:

What sort of ;expert' quotes his findings in mixed measurements;  2mm per foot . Surely the length of the boat has no bearing on the amount of expansion of a given material in identical conditions

The expert is in quote marks presumably because there is some doubt, I read it as it is the one that spoke to Fly Navy.

I rather like mixed measures, 2 parts rhum to 5 parts Coke.

As to expansion having no bearing on length, for the same material why not? Is the steel going to expand more or less because it is sections welded together? Or if the boat is longer, is the steel more expansive? ( pun intended ) Does a tube expand more than a solid bar of the same material?

Edited by Boater Sam
added more
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14 minutes ago, Ex Brummie said:

What sort of ;expert' quotes his findings in mixed measurements;  2mm per foot . Surely the length of the boat has no bearing on the amount of expansion of a given material in identical conditions

Possibly to couch his response in figures that can be related to, we all think of the length of a boat on terms of feet, adverts are generally for boats of X feet. Of course we should be using metric but hey it's a less than perfect world

Phil

Edited by Phil Ambrose
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21 hours ago, WotEver said:

He’s out by rather a large factor. The coefficient of expansion for Steel is around 12x10-6 per degree C. So a difference of temperature of 20C (unlikely I would have thought) gives 240x10-6, or 0.000240. Over 60ft that gives a difference in length of 0.0144ft, or 0.17”.

I remember when I was researching a case once (a good few years ago) that the temperature difference can be as high as 50C, but that was in a slightly more favourable latitude and was with a very dark matt paint.  That said your point is still very valid and even under these extreme and favourable conditions the expansion is not going to get anywhere close to the 1" quoted

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