2. Surface of glue cannot be dried during production. The main reasons are the glue ratio is inaccurate or insufficient stir evenly.
(1) the glue ratio is inaccurate: Part of glue cannot finish chemical reaction when the glue ratio is inaccurate. The glue cannot be fully dried without chemical reaction. That's why the glue surface cannot be dried or very sticky.
Solution: Please control the margin of error of glue ratio in 1% -1.5%.
(2) Glue is uneven mixing. Uneven mixing will lead to such problems: surface or part of glue cannot be dried and curing time becomes longer.
Solution: We must stir the glue evenly, especially the sides and bottom of the container, which is recommended to be 5-6minutes.
3. Phenomenon and explanation after curing of the glue
(1) The surface of glue will become whitish after put it under water for a long time. But they can restore to the original when you take it out at room temperature for 5hours. On the other hand, polyurethane glue is not easy to turn whitish under water.
(2) Regarding adhesive properties between Epoxy glue and silicone glue, or between epoxy glue and PVC. Both silicone material and PVC belong to difficult to bond material. Epoxy glue have some adhesion for PVC, but own poor adhesive properties with silicone material. Epoxy glue is easy to be break away from U type silicone tube.
(3) The glue surface seems a bit sticky after curing, so don't reel it in 24hours. It’s easy to stick to hand on surface or break if you pace it in 24hours. Because the glue is in a basic cured state in 24hours, has not been fully cured. Solution: Please reel or pack it after 48hours.
(4) Glue crack in position of LEDS. The main reasons are: Glue ratio is inaccurate, stirring uneven (part of glue is not curing), surface coating glue is not thick enough.