Perspex window thickness?

[IanVonLux]

Hi,

Looking at buying new perspex windows and struggling to find any recommendations about desired thickness.

I'm assuming that some clever person has worked out the minimum thickness of perspex required per maximum height or width of the window span???

Cheers,
Ian

 

[geem]

Hi,

Looking at buying new perspex windows and struggling to find any recommendations about desired thickness.

I'm assuming that some clever person has worked out the minimum thickness of perspex required per maximum height or width of the window span???

Cheers,
Ian

Mr Van de Stadt worked out that my portlights should be 13mm thick and the saloon windows 10mm. The boat is designed for heavy weather so may be OTT if your boat isnt

 

[IanVonLux]

Mr Van de Stadt worked out that my portlights should be 13mm thick and the saloon windows 10mm. The boat is designed for heavy weather so may be OTT if your boat isnt

I expect that I'm going to get a lot of similar responses, I'm hoping for something more scientific...

What are the dimensions of your saloon windows?

 

[scruff]

I expect that I'm going to get a lot of similar responses, I'm hoping for something more scientific...

What are the dimensions of your saloon windows?

You could employ beam theory for a simply supported beam. Work out the second moment of inertia and the load for forces derived from a body of water under X meters head.

Or you could just state that 8mm polycarbonate will be perfectly sufficient for anything short of a mortar round

 

[peteK]

Whats the thickness of the old windows?

 

[PetiteFleur]

I've replaced Perspex windows on a Jaguar 27 and a Moody33 - both were 6mm thick, long but only about 7" tall. I did in fact try and break the J27 windows which were badly crazed but it was very difficult and had to resort to a club hammer with the Perspex clamped in a heavy vice and it took about 3 blows before it broke. Very strong especially as it was not in it's frame. I was impressed with the strength.

 

[JumbleDuck]

Or you could just state that 8mm polycarbonate will be perfectly sufficient for anything short of a mortar round

Very strong especially as it was not in it's frame. I was impressed with the strength.

Agreed. I think the fixing will be the weak point, not the window itself.

 

[RobF]

I expect that I'm going to get a lot of similar responses, I'm hoping for something more scientific...

What are the dimensions of your saloon windows?

Hope this is a bit more what you're looking for...

My boat is Lloyds 100A5 rated and has a portlight thickness of 10mm. Height of portlights is 140mm, maximum portlight length is 670mm. Portlights are situated in CE Area A2.

 

[NormanS]

Would it not be a lot simpler of the OP took the trouble to give at least some idea of the size of his windows? Without that information, how does he expect to get an informed answer?

 

[PCUK]

Average yacht, Small to medium windows 6mm. Large windows 8mm. Huge windows 10mm.

 

[Poignard]

Mine:

Size: 16-5/8" x 4" with corners radiused 1-1/2"

Thickness: 6mm

Material: Perspex​

 

[greggron]

I expect that I'm going to get a lot of similar responses, I'm hoping for something more scientific...

What are the dimensions of your saloon windows?

With the greatest respect, you’ve given those who might help virtually no contextual information at all.

 

[geem]

I expect that I'm going to get a lot of similar responses, I'm hoping for something more scientific...

What are the dimensions of your saloon windows?

Whats the point? You havent metioned the size of your windows.

 

[Neeves]

I might have thought, possibly erroneously, Classification Societies would have this at their fingertips, or on their websites. Though finding the data might be difficult.

Jonathan

 

[Hoolie]

Average yacht, Small to medium windows 6mm. Large windows 8mm. Huge windows 10mm.

Sounds about right to me. I'd add "Large deck hatch 12mm"

 

[geem]

Sounds about right to me. I'd add "Large deck hatch 12mm"

My boat is built to Lloyds 100A1. Small windows are all 10mm thick. We have nothing less than 10mm

 

[FlyingGoose]

I had my front windows re done at 10 mm thickness nice shade of Blue Perspex and 16 mm for a very large hatch in the coach roof , which my daughter and her friend can easily stand on and jump around , no movement or give , Front windows seem solid at 10mm

 

[rszemeti]

My Feeling 1090 has 10mm for the side windows, 12mm for the front windows

Fron windows are roughly 550mm square ... side windows 1900 x 340mm

 

[stevie69p]

I have just reglazed the wheelhouse side windows on my LM27 using 10mm perspex. The windows are about 1.2m long by 0.6m tall. The 10mm seemed over the top when I was cutting to shape, but actually fine once fitted, and I feel happier with a good thickness of material where the fixings are.

 

[James_Calvert]

Don't know why he doesn't respond to the questions but when he was asking about re-engining he had an Arpege.