Crazed port lights and hatches, Any fix other than replacement?

mainsail1

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I know I do. I can't sleep with light streaming through the deck hatches on a long passage after a 0300 - 0600 watch.

The cover has a bit of bungy cord round the edge that is threaded through the hinge, just in case that F8 wind or the big green wave does not take it away.

Nothing is stabilised for UV given the amount of time it is exposed to it.
Well, you could knock me down with a feather! In all my years wandering around marinas I don't think I have seen a sailing boat with hatch covers.......unless the yacht is enormous and very very smart.
 

Sandy

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Well, you could knock me down with a feather! In all my years wandering around marinas I don't think I have seen a sailing boat with hatch covers.......unless the yacht is enormous and very very smart.
I hate to think what sun damage they have to the interior woodwork.

Perhaps the lack of shading has been the driver to clinical white interiors.
 

mrangry

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Two materials you can use to replace crazed Perspex :
Perspex but it will develop craze again
Polycarbonate/ Lexan much stronger does not craze as perspex does, it is used in security and bullet proof glass.
Try breaking two off cuts one of Perspex and the other of polycarbonate/ Lexan . P Lexan is so strong.
The problem is Polycarbonate/Lexan is softer a scratches so utmost care is required.
Both are easy to cut and champher.
Polycarbonate offers far less uv resistance than acrylic and as you say scratches a lot easier too
 

mjcoon

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Polycarbonate offers far less uv resistance than acrylic and as you say scratches a lot easier too
So if also "Polycarbonate... does not craze as Perspex does" what does UV do to it? Just make it go smoothly yellow? Not much an advantage! Perhaps an outer skin of toughened glass, as made for mobile phones, is what is required...
 

rogerthebodger

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So if also "Polycarbonate... does not craze as Perspex does" what does UV do to it? Just make it go smoothly yellow? Not much an advantage! Perhaps an outer skin of toughened glass, as made for mobile phones, is what is required...

Polycarbonate goes milky in UV light even the so called UV rpotected lke Lexan.

Toughtened glass will shatter if hit by a sharp object. I had toughtened and laminated glass in my wheelhouse windows and one shattered when hit by a wayward winch handle
 

mjcoon

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Polycarbonate goes milky in UV light even the so called UV protected like Lexan.

Toughened glass will shatter if hit by a sharp object. I had toughened and laminated glass in my wheelhouse windows and one shattered when hit by a wayward winch handle
I think that is a reasonable cost for allowing "wayward winch handle" wielders on your boat! "Crazed" must come into it, one way or another...
 

DAKA

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Is there really no treatment that will flow into the crazing and remove it like invisible car windscreen crack-mending systems do?
I’ve used Turtle wax Bug and tar remover ( from motorist DIY store) for the last 10 years or so on our 30 year old smoked hatch .
90% of the cracks vanish and it lasts the season
The hatch is more or less horizontal so it gets full uk south coast sun , I’m not sure how long it would last in the med.

Spray it on ( white opaque) rub it in a bit , leave it and it goes clear in about 10 minutes.

Pressure washer to clean the cracks first makes a better result but I dont always have a pressure washer to hand and it still a decent job.

NB. It is a bit slippery while drying so you don’t want to step on it for a day
 

ylop

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I hate to think what sun damage they have to the interior woodwork.

Perhaps the lack of shading has been the driver to clinical white interiors.
I imagine they have blinds on the inside? As with most things in life it will be a cost issue. Would you like to pay £3K more for your yacht to have hatches with our “no craze” guarantee for 7 years or accept that if left in UV there will be some cosmetic damage? Average charter owner is going to take the cheap option; average long term private buyer is going make covers because he wants 20+ years crystal clear and nobody can promise that.

I’m a bit surprised that Lewmar don’t do a rubbery cover like modern raymarine instruments. The only boats I see with hatch covers this far north are the ones that also have winch covers.
 

jac

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Hatch covers are available at swindleries for a not bad price (relative to expected swindlery price points ) and as said - anyone with a modicum of talent and sewing machine can run some up. I need to replace my hatches and will get covers when i do.
 

Bandit

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Polycarbonate offers far less uv resistance than acrylic and as you say scratches a lot easier too
Polycarbonate/Lexan is exceptionally strong, I have tried to break some 8mm with a wood axe, I could not! So for a hatch or forward window it is much stronger and you will mot break it in normal use. If you use it drill oversized holes for fastenings.
 

mrangry

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Polycarbonate/Lexan is exceptionally strong, I have tried to break some 8mm with a wood axe, I could not! So for a hatch or forward window it is much stronger and you will mot break it in normal use. If you use it drill oversized holes for fastenings.
Yes it is very strong but due to poor uv and scratch resistance not suited for hatch
 

Plum

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Yes it is very strong but due to poor uv and scratch resistance not suited for hatch
Not always true. Depends what grade of polycarbonate. Some have uv inhibitors, as in the grades specified by most car manufacturers for the headlights. Most still look very clear after 20 years. Occasionally you will see a car with milky headlights and that is often because it has been in a shunt. Aftermarket replacements are often of a lower grade of PC.
 

mrangry

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Sheet acrylic is inexpensive to buy in various shades to suit your needs. It can be cut easily using a jigsaw and edges routered if you want an angled edge. It can then be bedded in sikka or ct1 or indeed whatever your chosen adhesive is. If using for windows secured using screws or bolts, remember to countersink screw/bolt holes to prevent cracking and bed using butyl.....easy
 

Iliade

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I did manage to break one of the toughened glass windows in my then 40 odd year old Centaur. It took a jammed ladder and a falling tide though!

For an ocean crossing I'd use anti-bandit glass, toughened with a layer of plastic in the middle.

Optically, it is far better than any plastic after a few months service.

Unfortunately my current windows are curved, so would cost an arm and a leg to replace in glass like for like.
 
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