Wrapping the perspex of a bow hatch

[MapisM]

Can you guys think of any reason why the escape hatches normally used on the ceiling of bow cabins are made of transparent perspex?
Ok, it's often somewhat darkened/coloured, and so is mine - greyish, in fact.
But still transparent anyway, for reasons that I struggle to understand.

Now, bear with me.
A transparent hatch means that in order to not have light waking you up in the early morning, you must keep the internal sliding panel closed.
No big deal of course, but I'm noticing that (depending on the temperature differential), sometimes in the morning I find the internal structure of the hatch itself wet with condensation, possibly to the point of having some drops of water falling down.
This doesn't seem to happen if I leave the sliding panel under the hatch opened, I guess because air circulates better along the internal hatch surfaces.
Otoh, with the sliding panel left opened, as soon as the sun rises, the cabin is obviously filled with light.

This brings me to the point:
I'm wondering if it wouldn't be sufficient to wrap the external side of the perspex (maybe with a gelcoat-like colour film, but that's just a detail) to solve the problem, restricting light to enter also when the internal sliding panel is left open.
The reason for doing that on the external side is just for simplicity, since my hatch is very flat and regular externally, as opposed to the interior where it would be tricky to do a good job due to the handles and the internal frame.

Bottom line, do you think that an external wrapping could have an half decent durability in this application, and is there any specific film that you would suggest?
TIA!

 

[Mr Googler]

I tinted the inside of my hatches with limo black car window tint. Worked well.

Can’t see why it won’t stand up fine on the outside.

You could use a vinyl wrap for full blackout. If you don’t like it...peel it off!

They say don’t use car window tint on perspex due to the adhesives but after 2 years....didn’t notice any issues

 

[MapisM]

I don't mind what the material is designed for, as long as it can withstand external usage.
The films meant for car windows are still transparent though, while I'm aiming at fully obscuring the thing...

 

[vas]

P.,

are you sure the sun is waking you up and not simply old age?
comeon it's October, sun is late in the game!

...and to be helpful, how about doing a cloth cover, with a seam all around and a vertical part of a few cm with a strongish rubber band inside so that it wraps over and stays?
Depends on the lip and seal of the thing, but I guess it's easy enough to fabricate and easy to add/remove at will. Plus it should be good at protecting perspex from sun fade/crazing/etc

V.

 

[PalmaTarga]

window tint would be fine. There are many grades available depending on how dark you want it. Personally I would do it from the inside, you will need to apply it in the correct way, using a heat gun as you apply to a soapy surface. This will shrink it to fit. If you don't the sun will shrink it pretty quickly and will become wrinkly. Have a look at www.mdpsupplies.com, you'll find many options there.

 

[bluetooth]

Leave the side window hatches open to allow ventilation and stop the condensation and drips.

 

[petem]

P, a vinyl car wrap would be ideal but I suspect would have to bought by he roll and cut in situ. Alternatively, take some accurate measurements and ask a local signwriter (i.e. one that does vehicles) to cut you a piece to the exact size that you need. If you have a RAL code for your gelcoat / kiwigrip then they might be able to get a close match, otherwise you'll have to settle for whot or an off white. Despite the hatch being horizontal, I'd have though that it would last a few years before going wrinkly or peeling. Got to be worth a try for £50 or whatever.

 

[BruceK]

I find your predicament and complete odds with my experience. I may not be understanding of what you mean by sliding panel as I don't have such. What I have is a fabric covered thin plywood plug that slots and locks into the underside of the hatch. When it is in there is no condensation at all. When it is out condensation forms on the hatch perspex and drips down onto the bed or where ever the 3 hatches overhang. I'm assuming in my small boat 4 persons breathing probably exceeds what you have in your boat?
I can only presume then that your sliding panels are either not making a flush fit, or are not insulated in a way that prevents a cold surface on which to condense. Not sure if either of these can be remedied but worth a thought as an alternative solution as were I in your shoes I could not black out my hatches and not turn the interior of the boat into a gloomy dungeon.

 

[Mr Googler]

https://www.vinyldepot.co.uk/

I’ve used literally loads of the decorative and coloured stuff. I will stand up to anything! They do a Matt white if you really want to be boring. Nice bit of Japanese Oak would be different

 

[rafiki_]

P.,

are you sure the sun is waking you up and not simply old age?
comeon it's October, sun is late in the game!

...and to be helpful, how about doing a cloth cover, with a seam all around and a vertical part of a few cm with a strongish rubber band inside so that it wraps over and stays?
Depends on the lip and seal of the thing, but I guess it's easy enough to fabricate and easy to add/remove at will. Plus it should be good at protecting perspex from sun fade/crazing/etc

V.

I have a fabric cover as Vas suggests, same material as the tonneau and cockpit covers. Fits externally and I can take it off any time.

 

[jrudge]

I have gone the other way.

I have ply fabric covered blanks for the port holes to no need for curtains or blinds which is much nicer. As such I rarely remove the port hole covers and use the top for all light

 

[TheOrs]

...and to be helpful, how about doing a cloth cover, with a seam all around and a vertical part of a few cm with a strongish rubber band inside so that it wraps over and stays?

Like this? https://www.force4.co.uk/hatch-cover.html

 

[Mr Googler]

Like this? https://www.force4.co.uk/hatch-cover.html

I bought one of those.....useless. If you pull it tight with the lid open, it then sits on the seal and lets water in. If you pull it tight with the lid closed, the edge is thick and hardly tucks under the hatch lip.

I had proper covers made on my current boat with poppers onto the deck. Problem solved

 

[bigwow]

There you go get the sewing machine out.
https://www.sailrite.com/How-to-Make-a-Hatch-Cover-Video

 

[MapisM]

I may not be understanding of what you mean by sliding panel as I don't have such.

Sorry, in hindsight I appreciate that I was referring to the ceiling arrangement in my boat, which was actually custom built by the yard.
But one way or another, I've always seen bow hatches with some sort of internal blind, either rolling or sliding.
This arrangement is sort of irrelevant, though - what I'm after is a way to darken the perspex permanently, making the internal blind redundant, so to speak.
Anyhow, below is a pic of my current setup, just for the records.

Thanks everybody for all other suggestions, but I still think that an external wrapping is the easiest route.
After all, it wouldn't be a big deal to replace it every few years, if need be.
In the meantime, I also saw that there's plenty of wrapping films for sale online, also with some colours choice.
But if anyone can recommend a specific type/brand, I'm all ears!

 

[Mr Googler]

D-c fix

https://d-c-fixna.com/

 

[lambohill]

Hi, use Oracal Cast Vinyl wrap.
It is 7 years design and breathable application. Needs heated to correct temperature with an airgun to lose its memory shape, so properly applied is important.
I've used it very successfully in the med sun on my boat, even on hardtop with no colour fade etc. Quick wash, like new.

 

[malcolm2]

You might want to consider an "etched" material. This gives an effect similar to an old fashoined pub / shop window.
It does not give a totally obscure black out effect. But will cut the glare from bright early morning sun.
We used to supply precut panels to Fairline (eg SQ62) using this material.
The Fairline ones were I think applied on the inside of the hatch glass. Depending on where your hatch is, if applying on the outside, potentially the main source of wear and tear will be deck shoes walking on it not the weather.

 

[MapisM]

Deck shoes!?
Here in the Med, keelhauling is standard practice, for anyone who dares boarding with anything else than bare feet!

Thanks for the additional suggestions, folks. I will check out those brands/types to make up my mind... :encouragement:

 

[petem]

Deck shoes!?
Here in the Med, keelhauling is standard practice, for anyone who dares boarding with anything else than bare feet!

Thanks for the additional suggestions, folks. I will check out those brands/types to make up my mind... :encouragement:

P, Malcolm2 (post #18), is the man for these things. If I remember correctly, he was wrapping trains and jumbo jet tails (much to Margaret Thatcher's displeasure) with vinyl decades ago.