Acrylic vs Polycarbonate windshields


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Sadanorakman
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Acrylic vs Polycarbonate windshields

Post by Sadanorakman » Mon Jan 07, 2019 4:20 pm



...can someone clarify all this talk amongst these posts about polycarbonate? Is it simply ignorance or assumption?

To my understanding, the majority of aftermarket windshields are currently made from acrylic, which is vastly less impact resistant, and much more easily scratched than polycarbonate, which in comparison is a FAR superior material.

I'm currently looking for a replacement windshield, and am struggling like hell to find a polycarbonate GL1500 screen in the UK... Looks like I'm going to have to import one from the US. Seems I have to go for the likes of a slipstreamer or F4 product to get polycarbonate.

The cheapest acrylic one will cost me just £60, a polycarbonate one £175! Should I honestly spend three times the money on the polycarbonate one? Is one really good screen worth three cheap ones?

Does anyone know what the original OEM windshield is actually made out of?


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Re: Acrylic vs Polycarbonate windshields

Post by WingAdmin » Mon Jan 07, 2019 7:10 pm

I would definitely go for polycarbonate. Have a read through these topics:

viewtopic.php?p=275942

viewtopic.php?t=28374

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Re: Acrylic vs Polycarbonate windshields

Post by 823JIM » Mon Jan 07, 2019 8:47 pm

I am pretty sure the OEM shield on my 1800 was polycarbonate. I now have an after market acrylic one. It is three years old and still looks like new, I take great care about cleaning it so as not to scratch. Use plain water on micro fiber towel, just lay across windshield to let bugs and bird doo soften then gently wipe clean, then polish with Novus 1.

Air craft wind screens are acyclic https://www.ceebaileys.com/Aircraft-Win ... ndows.html so how easily they break I believe is over stated, they survive bird strikes. Polycarbonate is too flexible for aircraft and will not stay sealed, and actually scratches easier than acrylic (thus the need for hard coating on polycarb, which can peal and flake).

My thoughts on the 3 to 1 pricing was like yours. If I were to pay that much for one I would probably leave a buggered up one on longer rather than replace it when it really should be.

Just my opinion, but some food for thought.
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Re: Acrylic vs Polycarbonate windshields

Post by WingAdmin » Mon Jan 07, 2019 9:37 pm

823JIM wrote:
Mon Jan 07, 2019 8:47 pm
I am pretty sure the OEM shield on my 1800 was polycarbonate. I now have an after market acrylic one. It is three years old and still looks like new, I take great care about cleaning it so as not to scratch. Use plain water on micro fiber towel, just lay across windshield to let bugs and bird doo soften then gently wipe clean, then polish with Novus 1.

Air craft wind screens are acyclic https://www.ceebaileys.com/Aircraft-Win ... ndows.html so how easily they break I believe is over stated, they survive bird strikes. Polycarbonate is too flexible for aircraft and will not stay sealed, and actually scratches easier than acrylic (thus the need for hard coating on polycarb, which can peal and flake).

My thoughts on the 3 to 1 pricing was like yours. If I were to pay that much for one I would probably leave a buggered up one on longer rather than replace it when it really should be.

Just my opinion, but some food for thought.
Aircraft windscreens are in fact acrylic, but they do NOT survive bird strikes. The birds come right through into the cockpit.








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Re: Acrylic vs Polycarbonate windshields

Post by 823JIM » Tue Jan 08, 2019 12:39 pm

https://www.piedmontplastics.com/applic ... indshields

"Motorcycle windshields are made from either acrylic or polycarbonate, and each material offers its own advantages. Impact modified acrylic has a glasslike clarity, while polycarbonate windshields that have been hard coated have high impact and abrasion resistance. Both materials are extremely durable and will not shatter on impact." Quote from Piedmont Plastic

"Plexiglass Sheet - Acrylic Features: •Plexiglass is 17 times stronger than glass, but only 50% of the weight !" Quote from professionalplastics.com

I know polycarb is more flexable thus less likely to break, but still believe acrylic is a viable less expensive option. Unless the plan is to hit a 15# goose at 115mph, then I don't think polycarb or acrylic is going to be your main problem.
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Re: Acrylic vs Polycarbonate windshields

Post by WingAdmin » Tue Jan 08, 2019 2:31 pm

One of the main benefits of polycarbonate is that it BENDS instead of breaking into sharp edges. If you hit something, you ARE going through the windshield. Would you rather it bend out of the way, or shatter, leaving sharp edges for you to travel across?

This has been posted here many times before:




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Re: Acrylic vs Polycarbonate windshields

Post by Sadanorakman » Tue Jan 08, 2019 3:40 pm

I thought I was replying to an old windshield thread last night, not creating a new one.
WingAdmin did you step in and create a new thread on my behalf?

One of the posts I'd been reading argued that polycarbonate was more prone to scratching than acrylic, unless it had been hard-coated with a surface treatment.

I just looked up the shore hardness of both materials, and if these numbers are to be believed, they seem to have a reasonably similar hardness.

I appreciate that a Material's hardness is not a direct measurement of its abrasion resistance, but surely the two are linked? The harder a material the more resistant to abrasion? I can't seem to find anything more specifically appropriate regarding abrasion testing of these two materials. There's a very long list of different abrasion tests for all sorts of materials which is too great a minefield for me to wade through (ASTM, ISO, DIN, JSA...)

Polymethylmethacrylate (Acrylic) (supposedly) has a shore hardness of 90.000 to 99.000.

Polycarbonate (supposedly) has a shore hardness of 90.000 to 95.000.

This would tell me they would scratch reasonably similarly, but very happy to be educated on this!
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Re: Acrylic vs Polycarbonate windshields

Post by WingAdmin » Tue Jan 08, 2019 9:01 pm

I did separate the threads, as the original thread was about windshield heights, and the discussion had completely changed to acrylic vs polycarbonate, so I separated them - makes it easier for others to find in future.

Polycarbonate is definitely softer and more easily scratched than acrylic. It also has one other undesirable quality: it turns yellow when exposed to UV (i.e. sunlight).

For this reason, it is given a coating that both blocks UV and provides a very hard surface to prevent scratching. The end result is that the polycarbonate ends up being much more scratch resistant.



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