Hesalite crystal facts

Jul 30, 2009,03:36 AM

There has been much said on hesalite crystal as used on the Speedmaster prof

Hesalite or from other supplier could also be brandname Perspex. Both of them a PMMA sheet

Tradename      Material            Manufacturer                                                 

Hesalite             PMMA sheet       G-S Plastic Optics        gsoptics.com

Perspex            PMMA sheet        Lucite International    www.luciteinternational.com


Proporties of the materiel is.

• Exceptional light transmission with virtually no colour bias - even in thick blocks.

• Excellent resistance to outdoor weathering.

• Good resistance to impact.

• A high gloss, hard surface.

• High tensile strength and rigidity.

• Easily thermoformable with simple workshop tools.

• Easy to clean.

• Capable of being fully recycled.

My question, wanting the original speedy was always: How will it take scratches. What I found stated on perspex was:

"Numerous test methods have been devised and a simple guide for plastics is the pencil scratch method using a set of graphite pencils covering the hardness range from 6B to 9H. 'Perspex', which is one of the hardest of the thermoplastics, is scratched by a 9H pencil only"

BR Hans


Some links                                       

UL yellow card:





Datasheet Perspex:


Handbook Perspex:


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 By: AndrewD : July 31st, 2009-04:18
Dear Hans, I really appreciate you putting this summary together. I am a ‘facts man’ and it's great to have all this information available. The summary of the different optical polymers and co-polymers was very interesting as was the manufactu...