Frequently Asked Questions

Insulcast Questions:

We do not offer urethane products in our Insulcast® line.  Instead, we offer a series of flexible epoxies (Insulgel) that are engineered with high elongation and low coefficient of thermal expansion without the health hazards associated with isocyanate exposure.

Depending on the application, an epoxy or a silicone may be the right solution for your application. 

  • Epoxies have great mechanical strength and cure hard, making it difficult to remove which is great for anti-piracy. Epoxies have strong chemical resistance and can operate at temperatures up to 311°F / 155°C.
  • Silicones have low viscosity and cure much softer which allows for repair of electronic components following cure. They are good for high temperature applications, with some options reaching a service temperature of 500°F / 260°C.

Epoxies bond very well to metal and porous parts without the need for a primer. Our silicones require a primer to achieve maximum bonding strength at the surface of each part. The presence of gaps following cure will depend on many factors including product viscosity, cure shrinkage, coefficient of thermal expansion, and the environment to which the product is exposed during the application. Consult with your ITWPP Regional Sales Manager for assistance in choosing the appropriate product for your application.

The typical shelf life for both epoxy and silicone products is 12 months.

“The product isn’t curing.  The whole batch remains liquid, soft, or tacky.”

Possible Cause

Solution

Incorrect mix ratio.

Verify that correct mix ratio is being used. Calibrate mix equipment (if applicable) and adjust mix ratio as needed.

Ambient temperature too low.

Move part to warmer area or low temperature oven. Recommended ambient cure temperature: 77°F +/- 2°F (25°C +/- 2°C)

Bake cycle too short.

Check instructions and adjust cure cycle

Contamination.

Check cleanliness of equipment. Check to see if other products, varnishes, and resins were cured in the same oven.  Cover containers.

Moisture, Humidity.

Keep containers covered.  Cure in a dry area or low temp oven.

 

“The product isn’t curing consistently. There are soft areas, a marbled effect or 1 or 2 units in a batch that do not cure at all.”

Possible Cause

Solution

Incomplete mix.

Increase mix time, scrape bottom and sides of container, use mechanical mixing.

Mixed and cured in the same container, bottom of container never completely mixed.

Use a separate container for mixing and curing. 

Scraping the last bit from the can, resin in the bottom of the can or trapped under the lip is not thoroughly mixed.

Do not scrape all resin out. Alternatively, use a two step mix process: After thoroughly mixing the resin, pour it into a second container and mix again. Scrape side and bottom of can while mixing.

Contamination.

Check cleanliness of equipment. Check to see if other products, varnishes, and resins were cured in the same oven. Cover containers.

 

“The product is cracked following cure.”

Possible Cause

Solution

Product selected for use is too rigid.

Choose a more flexible or resilient compound (higher elongation %).

Product is not uniformly thick surrounding embedded object – tends to crack where thick and thin sections meet.

Use an inert material (gravel, sand, marbles, or scrap material) to displace resin and make thickness more uniform.  Alternatively, choose a more flexible (higher elongation %) product.

Embedded object has angular shape and sharp corners.

Use porous tape or other material to mask angles.

Mold not smooth, burrs protrude or not properly cleaned after prior use.

Polish off burrs prior to potting.  Ensure that any remnants from previous use are removed.

 

“The unit sticks in the mold after cure, or the multi-part mold won’t open.”

Possible Cause

Solution

Mold not smooth, burrs protrude or not properly cleaned after prior use.

Polish off burrs prior to potting. Assure that any remnants from previous use are removed.

Mold release not applied or improperly applied.

Ensure that all interior surfaces are uniformly coated with release agent.

Mold release not applied to mating surfaces, adhesive has seeped between parts of the mold and cured.

Ensure that all interior surfaces are uniformly coated with release agent.

 

“Product doesn’t adhere to potting cup, case, or container.”

Possible Cause

Solution

Container isn’t clean.

Ensure that the container is clean and free of moisture, grease, oil, or release compounds used in mold manufacture.

Excessive adhesive shrinkage during cure.

Choose a resin with low shrinkage. Minimize free space around the embedded object. Use inert material to displace resin. Choose a more flexible or resilient resin.

 

“The cured product contains voids, pin holes, surface bubbles, or pocks.”

Possible Cause

Solution

Resin poured over the embedded object.  Resin cascades around the object trapping air.

Pour adhesive in the corner or alongside the part in an empty space. Allow adhesive to flow up from the bottom to impregnate and encapsulate the part.

Air entrapped in adhesive during mixing or handling.

Use a flat blade when mixing. Tap units gently on the table before curing to dislodge air. Degas with vacuum process to remove air prior to curing.

Air bubbles on the surface of the part after pouring adhesive into container.

Lightly spray the surface with isopropyl alcohol to remove the bubbles. Bake at 150°F / 65°C to flash off the alcohol. 

General Questions:

The product information you are looking for can be found on our Safety Data Sheets Page.

Products can be purchased through our distributor network. Click here to find the distributor closest to you.