Substitution: Alternatives to Clear Casting Resin

Minimizing Hazard Exposure through Material Substitution

Products such as epoxy resin, urethane resin, and polyester resin contain chemicals known to be powerful irritants and sensitizers. Individuals exposed to these chemicals, by way of contact with the skin, eyes, or respiratory system, can experience severe asthma attacks, allergic reactions, and other permanent harm. Repeat exposure, even at low doses, increases the risk of such reactions, including individuals who are otherwise healthy.

Preventing exposure to these chemicals is a critical step in eliminating the health hazard. The most effective methods to prevent or reduce exposure are elimination and substitution. In the context of resin use at the GSD, elimination of a hazard would entail designing the project so that the product is no longer needed, substitution would entail the use of an alternative product, one that has fewer or less severe associated hazards.

The GSD Fabrication Lab selected and tested products for their potential use as alternatives to clear casting resins; products that minimize the hazard exposure through material substitution. The samples display the varying degrees of transparency that can be achieved in a range of geometric possibilities for each product


The table below compares the alternative materials. Click on any column header to sort the table by that factor. Click on a method name for more information about the process and related considerations.

  • "TIME" refers to the total amount of time required for a process, including preparing the material as well as curing or drying time. It does not include sourcing the material nor any time that might be required while waiting for machine time to become available, etc.
  • "SKILL LEVEL" refers to the relative amount of skill or experience required for a given method.
  • "Transparency" scale
  • "Special Equipment"
  • "Health and Safety"

 


Reference Image for Transparency






 MATERIALCOST ($/cubic inch)

TIME for Sample Cube

SKILL LEVEL (1-5)

TRANSPARENCY (1-5)HEALTH & SAFETYSPECIAL EQUIPMENT

Golden Acrylic Leveling Gel$1.14N/A (never achieved full cube, would take over 1 week, estimated)



Objet Vero Clear$19.85

2 hours, unpolished

4+ hours, polished

2


3

5 (when polished)

Hazardous when in liquid form. At least one constituant chemical is considered to be carcinogenic and possibly mutagenic.


Once cured, part is considered to be non-irritating and not sensitizing to skin.


Dust from sanding / polishing must not be inhaled.

Sandpaper and polishing compound

Clear Glycerin Soap Base$0.221 hour32

Constituent ingredients can cause eye damage, skin irritation, and are toxic to aquatic life.


Use of product requires working with a hot liquid, protect skin, face and eyes from burns and splashes.

Hot plate, double-boiler

Smooth-On Encapso K$0.5017 hours35

Part A: No data on possible toxicological effets available.
Part B: No data on possible toxicological effets available.


Use vinyl gloves to limit skin exposure and splash goggles to protect eyes.


Smooth-On SORTA-Clear 40$0.8017 hours

3

4 (when degassed)

1

3 (when degassed)

Part A: No data on possible toxicological effets available.
Part B: No data on possible toxicological effets available.


Use vinyl gloves to limit skin exposure and splash goggles to protect eyes.

Vacuum chamber for degassing

Museum Gel$1.24N/A (remains viscous, cannot form self-supporting cube)15

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