Re: ADHESIVE PROBLEM

Dennis Storzek
 

On Fri, Oct 18, 2019 at 04:32 PM, Tim O'Connor wrote:
ABS is NOT an acrylic material.
Errr, Tim, ABS is Acrylonitrile Butadiene Styrene. Here's a brief explanation from Wikipedia:

ABS is a terpolymer made by polymerizing styrene and acrylonitrile in the presence of polybutadiene. The proportions can vary from 15 to 35% acrylonitrile, 5 to 30% butadiene and 40 to 60% styrene. The result is a long chain of polybutadiene criss-crossed with shorter chains of poly(styrene-co-acrylonitrile). The nitrile groups from neighboring chains, being polar, attract each other and bind the chains together, making ABS stronger than pure polystyrene. The styrene gives the plastic a shiny, impervious surface. The polybutadiene, a rubbery substance, provides toughness even at low temperatures.

Back when I was building patterns for resin kits I wanted to build on a base solid enough to resist any warpage of the laminated patterns, so I chose 1/2" thick cast acrylic (Plexiglass) because it was readily available, easily cut with a table saw, and had a coefficient of thermal expansion similar to the styrene the pattern would be built of. Unfortunately I found it difficult to cement small bits of styrene to the acrylic with the techniques I was comfortable with, so I laminated a sheet of .020 styrene to the acrylic base to give me a stable styrene surface to build on. Tenax was my cement of choice to do the lamination, and it never failed.

I will admit that Tenax has such a high evaporation rate that it may be difficult to work with, but it will dissolve acrylic, styrene, or ABS.

Dennis Storzek

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