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HP Forum Archive 21

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HP calc case thermoplastic types
Message #1 Posted by Duane Hess on 16 Nov 2012, 2:05 a.m.

For strange mysterious reasons the thought crossed my mind what is the softening temperature of the plastics used in the HP calculator cases? Always thought the cases were an ABS type thermoplastic (don't ask me why).

Does anyone know the thermoplastic type & softening temperature of the classic, woodstock, etc. cases. No particular reason to know, just struck me as "that would be interesing".

(about the same time my aneurysm set it, but whatever)

      
Re: HP calc case thermoplastic types
Message #2 Posted by Bruce Larrabee on 25 Nov 2012, 10:29 p.m.,
in response to message #1 by Duane Hess

I don't know the answer to your question but anything you find out I would like to hear about.

I can tell you one interesting fact (well, I found this very interesting).

The case plastics are generally extremely resistant to acetone.

M.E.K. (Methyl Ethyl Ketone) does affect it but it does not melt it. More like oxidizes it.

            
Re: HP calc case thermoplastic types
Message #3 Posted by Paul Berger (Canada) on 25 Nov 2012, 10:50 p.m.,
in response to message #2 by Bruce Larrabee

I have a MEK based adhesive made by Plastruct called "Plastic Weld" that does seem to melt the surface of the plastic used on a 41 case. I have successfully used to to repair cracked parts, which it is very good for as it is a thin as water, and will seep into cracks.


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