Window Saga. New Thread. Small Question.

[Chotu]

Originally Posted by rslifkin

There's always the half-joking worst case answer to reducing the heat stress: Some kind of fan setup to blow a bunch of air across the windows to cool them when a significant heat differential is detected. I wouldn't actually recommend doing this, but it might work...

I have a similar type of approach with similar difficulty, but I think this is the real answer to everything:

Get the hell off the dock. Ha ha ha.

Somehow at anchor this doesn’t happen. I guess the boat is moving around enough that the heat is more evenly distributed and not just on one side.

Racing to try to get her liveable as one guy. It’s slow going. But with my lung issues, I can’t hire a helper.

[ahun]

What about just shading them in the morning? Let them heat up gradually and evenly.

[Chotu]

Originally Posted by ahun

What about just shading them in the morning? Let them heat up gradually and evenly.

That would be a great idea. But there is a scratch risk. It’s polycarbonate. Even a tarp rubbing on it will ruin it.

[LittleWing77]

My thoughts would be to go with the natural inclination of the polycarbinate and find a way to accomodate that.

Generally, when you try to pin down a material to make it expand/contract in a way that it's not doing, it will ultimately become a point of failure (i.e. it creates a repeated unnecessary stress). You probably already know this.

Hopefully Narfi's idea will work.

(I second the point about black... sorry, but there's a reason that boats are almost universally white and it has to do with our friend, the sun, and its UV...)

Warmly,
LittleWing77

[wolfgal]

please be nice guys. i've never worked with poly carbonate, and what i do know about it comes from refit videos i'm only brave enough to give this a crack, because i know how difficult this window business has been for Chotu.



perhaps not at all possible but

i'm imagining a kind of brace-against frame structure that has horizontal slats running across the window (kind of like venetian blinds but spaced farther apart and/or not very thick).

my idea is that the frame itself serves two purposes: to hold the windows when temps change considerably while providing lengths of shade below them to prevent the heating of the windows as well

what to make it in, think this depends on just how heat sensitive the panes of poly are. aluminum, wood, or the smoked poly itself...

in any case, good luck Chotu!

wolfie

[Chotu]

Don’t sell yourself short! That’s one of the best ideas I’ve heard. Ha ha.

I may not do it only because I don’t feel like building all of that. LOL I have a lot to do of course. So I have to do things as quickly and as properly as possible at the same time. Certainly that would fix all of the problems and help a lot with reducing the thermal load inside the boat. Which is why I think maybe it would be a good idea. But also a large project.

I’ll probably just Capture the errant edges with more channel and framework, like you can see in the top and bottom of the current windows, and if for some reason that doesn’t work, I think I’m going to go with this idea. I really like the shading aspects.

Originally Posted by wolfgal

please be nice guys. i've never worked with poly carbonate, and what i do know about it comes from refit videos i'm only brave enough to give this a crack, because i know how difficult this window business has been for Chotu.



perhaps not at all possible but

i'm imagining a kind of brace-against frame structure that has horizontal slats running across the window (kind of like venetian blinds but spaced farther apart and/or not very thick).

my idea is that the frame itself serves two purposes: to hold the windows when temps change considerably while providing lengths of shade below them to prevent the heating of the windows as well

what to make it in, think this depends on just how heat sensitive the panes of poly are. aluminum, wood, or the smoked poly itself...

in any case, good luck Chotu!

wolfie

[Chotu]

Originally Posted by LittleWing77

My thoughts would be to go with the natural inclination of the polycarbinate and find a way to accomodate that.

Generally, when you try to pin down a material to make it expand/contract in a way that it's not doing, it will ultimately become a point of failure (i.e. it creates a repeated unnecessary stress). You probably already know this.

Hopefully Narfi's idea will work.

(I second the point about black... sorry, but there's a reason that boats are almost universally white and it has to do with our friend, the sun, and its UV...)

Warmly,
LittleWing77

OK. Thank you for the contribution. I agree. Going with the natural properties of the material and not fighting it too hard. That’s probably the way to go.

I just have to capture those parts that stick up, so that it can slide along a track and go upward into the top frame piece. Which has plenty of space there to support any amount of expansion.

[wolfgal]

that was nice of you, Chotu. thanks.


if shading is the key, then there must be a solution. the problem is that poly scratches...

perhaps make a window cover out of a soft, non-scratch fabric like a felt (with a certain thickness)

you can cut out large portions of it (say, like horizontal lines or whatever so to be able to see outside from below), according to how much shade you think you might need


maybe worth a try and to keep onboard for those really hot days at the dock

if it helps regulating the temps, maybe this would do the trick?

[stormalong]

I know you said you do not want to pay the weight penalty for glass.

How much weight difference are you talking about? 50 feet is a lot of cat and a lot of buoyancy. Could you save some weight elsewhere?

The other issue is the bond between the poly-carbonate and the sealant. The more the movement, the greater the need for elasticity and greater the possibly of the sealant detaching.

[bcboomer]

We have light coloured Phifertex on our dodger windows that don't scratch the O'Sea plastic. I'm pretty sure polycarbonate is harder than the O'Sea.
You could remove them when you don't have the particular condition that causes the problem to minimize the risk.

Or you could have some shades made like used on the Manta cats.

[Djarraluda]

Originally Posted by Chotu

That would be a great idea. But there is a scratch risk. It’s polycarbonate. Even a tarp rubbing on it will ruin it.

Can you rig an awning to provide the shade? From cabin top to guardrail and down toe rail, then roll it up when things warm up, stow away when at sea and spray is flying to provide the temperature stability.

Alternative is to rig a grass watering system a leaky hose arrangement and dribble water there. Use a solar cell and timer to trigger it.

[Olly75]

If its only on one side and temporary due to your current situation rig up an awning/simple shade at night and once the temp differential between inside and outside has reduced you can take it down.

[Ribman]

Would you consider something like this? I googled rv window sunscreen and this happened to be first result. Seems it might be a reasonable compromise, reduce heat and keep visibility.

[Chotu]

Originally Posted by stormalong

I know you said you do not want to pay the weight penalty for glass.

How much weight difference are you talking about? 50 feet is a lot of cat and a lot of buoyancy. Could you save some weight elsewhere?

The other issue is the bond between the poly-carbonate and the sealant. The more the movement, the greater the need for elasticity and greater the possibly of the sealant detaching.

Yes, that was always the issue. That’s why 795 failed. . That’s why there is no sealant now. The frames do it all.

At $300 or $400 a sheet, I’m not ditching this polycarbonate I just bought. Unless you set up a GoFundMe for me and collect the money to pay someone to install glass.

[Chotu]

Originally Posted by Ribman

Would you consider something like this? I googled rv window sunscreen and this happened to be first result. Seems it might be a reasonable compromise, reduce heat and keep visibility.

Do you have a link for those covers? That’s worth looking into. They look very nice.

All of this stuff about shade is welcome because it’ll save fuel for air conditioning, even though it’s off topic. Topic was “what’s the best way to capture the Wiley edges of the polycarbonate to keep them against the boat?’