new "sexy" windows

[Northeaster]

Well, I finally got around to replacing my non opening portlights (deadlights) according to the advice on the "sexy windows" thread.

I believe they turned out very well, and look great. I have posted a couple of pics in the photo gallery under Yacht maintenance.

Thanks to all of you who replied to my questions.

[Benjamaphone]

Nice job! Can I ask what type of material you used for the glass?

[Northeaster]

Ben - After reading many posts here, on the lexan / acrylic debate, and listening to the advice of the local vendors (who sell both), I used 1/4" acrylic. The holes are only 5 1/2" high x 20" long, so they felt that would be strong enough.
I used 3M VHB tape for adhesion, as well as black Dow Corning 795 constuction / glazing ahesive silicon to seal the edges.

The old windows had through-bolted plastic frames, which did nothing, as the old acrylic panels were just siliconed to the outside of the frames!

[Benjamaphone]

Good choice on the acryllic. As you know, the lexan/acryllic debate has raged and I don't think that any consensus has been reached. However, it is my opinion that cast acryllic is very strong and is the superior material. I don't know much about sealing non-opening ports but I'm sure that the tape/silicone combo will work well.

[CanQua]

If you don't mind me asking, did you find an acrylic that is uv resistant? At work we stretch acrylic and it is about 10x the strength of cast(and about $100 a square foot), but we normally wrap that in a polycarb and also have a few coatings. I've asked and always been informed that the uv will yellow the acrylic in about 5 years without protection. However, what we call an engineer and someone who is actually qualified are two separate things.

Not trying to stir up any debate, just curious as to the use of the acrylic that I have access to.

[Zephyr's Aura]

Aircraft windows have been made of acrylic for years. In nearly 30 years I've never seen one yellow. I have seen them craze, and if cleaned with anything containing ammonia or sodium hydroxide they will turn milky. If you want to protect them from UV damage use an acrylic past wax. Finish 2001 by turtle wax works extremely well. Clean them only with soap and water, keep them waxed, and they will last a very long time.

Tim

[CanQua]

Yes, we do make many aircraft windows out of stretched acrylic, normally bonded with a layer of polycarbonate for scratch resistance. I'll try to take a look around today and see if I can't find out exactly what type of acrylic and polycarb we use. I don't think any of the windows we make here are straight acrylic(which would be covered with a scratch resistant coating), but I'll check into that as well. Because we stretch it, and then bond, it might be the particular type that stretches well. A quick google search shows there are indeed resistant varieties, though you'd be hard pressed to define resistance.
Didn't mean to hijack the thread, anything further on this topic and i'll find a more appropriate post.

On topic:
I forgot to mention, you did a great job replacing your windows. It really looks fantastic.

[Northeaster]

CanQua - thanks - I am glad you mentioned UV, as I hadn't given it much thought lately. I believe they have some UV coating, but I will follow Zephyr's advice and wax them, to make sure they are protected.

Mine are quite dark tint, so I don't think yellowing will be a problem. I am not worried about getting 20 years out of them, but would like to see them still looking decent in 10!

[CanQua]

I would go back to edit my mistakes, but am unable on this forum. I'd leave it alone, but hate to have bad information out there, especially when I'm the one giving it. Corrections are in red below. I'll try to better gather my facts before posting in the future.

[quote=CanQua;177748]Yes, we do make many aircraft windows out of stretched acrylic, normally bonded with a layer of polycarbonate for Impact resistance(many times with a interlayer of urethane sheet like the E2C side windows). I'll try to take a look around today and see if I can't find out exactly what type of acrylic(MIL-PRF-8184F ) and polycarb(MIL-P-83310) we use. I don't think any of the windows we make here are straight polycarb(which would be covered with a scratch resistant coating I was Incorrect, the rear windows for the F16 are indeed straight polycarb, but coated outside for uv and scratch resistance and inside). Because we stretch it, and then bond, it might be the particular type that stretches well(no, its just the highest grade available and stands up better to chemical attack, including salt water). And understand that we take the highest grade and stretch it to improve it's bond making it about 10X stronger than cast. It would be a great material, but expensive for any boat
Didn't mean to hijack the thread, anything further on this topic and i'll find a more appropriate post.

Not sure about the grade you've got, but it should hold up well to sunlight for many years even at the lowest grade. I know what we use blocks 100% of the UV at 320nm and if your is similar you'll have no uv damage to fabrics and such except where sunlight hits from an open hatch.
If you want to shoot me a pm I'll happily research the exact material you've used and give you a better understanding of what it's capable of, and how best to care for it. I'm not a chemist, but do have access to one if needed
and No, I'm not a salesman (in case you can't tell that from my ramblings) I think the only marine thing we make here is a window for a semi-submersible(used to be called glass bottom) cruiser.

My apoligies for the misleading information,
James AKA CQ

[Northeaster]

Can - thanks for the corrections!! I used a fairly standard acrylic, called Acrylite. I believe it has some UV protection. At this point they are in the boat, so I will not worry about it either way!! If they do not hold up well, I will report back here. I am quite sure I will get at least 5-10 good years out of them!

Take care!

[hellosailor]

Tim-
FWIW, Turtle Wax's MSDS at http://www.turtlewax.com/res/msds/T026R.pdf says that 2001 product contains 5-7% petroleum distillates, and that makes it forbidden by all the plastic glazing manufacturers. Could be that you use it little enough, and your plastic is good enough, so it hasn't hurt yet. But they all say "no" petroleum products, at all.

[GordMay]

Originally Posted by Northeaster

CI used a fairly standard acrylic, called Acrylite...

Saying you have “Acrylite” glazing is a lot like saying you have a General Motors vehicle.
There are several types & grades of Acrylite* BRAND Acrylic Sheet** (GP, AR, FF, etc).

Evonik Degussa acrylic sheet and acrylic molding compound products are manufactured and marketed under the ACRYLITE® tradename in the Americas.
Evonik Degussa manufactures and markets these same products under the PLEXIGLAS® tradename everywhere outside of the Americas.

** Acrylic Sheet: Acrylite, Plexiglass, Lucite, Perspex, etc ...

[hellosailor]

I sometimes wonder if ALL the glazing makers prefer mass confusion. I don't think I've ever seen glazing sold in any "retail" store (as opposed to a plastics supplier) where nayone made an effort to show there were different grades of the stuff with different properties.

Much the way the Howard Johnsons' HoJo restaurants used to quietly serve their own "HoJo Cola" when a customer asked for a Coke. Ain't the same thing at all.

[Zephyr's Aura]

Originally Posted by hellosailor

Tim-
FWIW, Turtle Wax's MSDS at http://www.turtlewax.com/res/msds/T026R.pdf says that 2001 product contains 5-7% petroleum distillates, and that makes it forbidden by all the plastic glazing manufacturers. Could be that you use it little enough, and your plastic is good enough, so it hasn't hurt yet. But they all say "no" petroleum products, at all.

I've been in the aviation business for nearly 30 years. I'm and airframe and powerplant mechanic and inspector (IA). I've been using Finish 2001 weekly on my aircraft windows for years. It has never done any damage and makes the windows clearer by filling the very small scratches. I'm also an aerobatic competition pilot. The aircraft I fly, an Extra 300, has a canopy that cost $18,000.00. Believe me when I tell you I wouldn't use anything on it that would cause damage.

Tim

[hellosailor]

Tim-
I take you on your word at that. Personally I use Windex on plastics--and they also say not to use that because it is ammoniated. I'm just pointing out that while it may work very well for you--that use is against the makers instructions. The glazing you get on aircraft might be a substantially higher grade than what is used for deadlights on boats.
Consider if you will, how many cars have "foggy" headlight covers. original equipment optical-grade plastic housings, that have taken UV damage on the streets in five years or less. Why? And why don't boat glazings fog up the same way?

It's either that all the "same" plastics are very different, or some of the "harmless" products aren't getting along very well on some of the plastics. (Could be something in the car washes, for all I know, although I'd think they use aqueos waxes.)

I'm afraid to ask what a tin of "FAA certified" [grin] canopy polish would cost.