3 tips to cast clear epoxy resin in thick layer
How to succeed in casting clear epoxy resin ? What is the secret to obtain a crystal clear resin with no disappointing side-effects , such as bubbles , yellowing or shrinkage ?
1. CHOOSE THE BEST EPOXY RESIN FORMULA FOR YOUR PROJECT
Many epoxy resins can be found on the market. But not all of them are good. What is more, you should not use any resin without being sure that it is properly compatible to your own application. Do not think every epoxy formulas are equivalent and will do the job !
Dare to opt for premium epoxy
First of all, when it comes to cast clear resin, make sure the formula you choose is a premium quality resin. Premium quality resin means that the raw materials selected to be incorporated in the formula are of highly standards. Many formulas on the market are made of standard raw materials. Some of which may contain particules of impurities. Sooner or later, the particules may cause a yellowing of the resin. UV resistants additives are by no mean a definitive cure against this phenomenon. However with a premium formula , your resin has a better chance to resist.
Thickness is the key
Second of all, there is a formula for each kind of application. Thickness casting being one of the main criteria when it comes to compare different products.
When you pour an important mass of resin, you have no choice but being patient. You must select a resin with a long pot life, that will cure slowly .
Actually, if the resin ”kicks” too quickly, if the explosion is too sudden and it hardens to rapidly, you are very likely to observe important shrinkage effects, yellowing, unsightly waves on the surface .
When you choose a resin with a slower cure, you allow your resin to catalyse properly for the mass , preserving a smooth surface and a perfect crystal clarity.
In a nutshell, your will have to make a choice : if you opt for a more rapid potlife, you woud pour your resin in more stages, which implies many preparations and operations, or cast a thicker layer but allow the resin to cure slowly, with a controlled exothermic reaction ( which is the heat created by the chemical reaction of the friction of the molecules from part A and part B)
Read more info on exotherm phenomenon in our coming article !
2. CAST YOUR EPOXY RESIN IN MORE STAGES
If the maximum thickness allowed with the formula is 1 inch, as it is the case for Chill Ice n°1 , you should stick closely to thi
However, should you pour more than 1 inch, you will have to proceed by successive stages. In that case, you must wait until the first layer has cooled down to 22°C . Otherwise, the heat of the first layer will accelerate the cure of the second layer, implying possible negative side-effects of an uncontrolled exothermic reaction.
Please note, that when maximum thickness is indicated , it always refers to a cubic mass 1” x 1” x 1”.
3 / MINIMIZE AIR BUBBLES FORMATION IN YOUR RESIN
The higher the viscosity of the resin, the more difficult it is for the bubbles to naturally pop up out of the resin. Resins with low viscosity , similar to water, are easier to degaze naturally.
In addition, the stirring technique is another important parameter to control. It is also highly advised to use a flat spatula , be it in metal or plastic. Avoid round wooden stick at all costs. Do not use a blender or mix vigorously which would create additionnal air bubbles.
Check this article for more tips to limit air bubbles.
The secret to obtain amazing results with clear thick epoxy resin casting
Be patient, careful and above all , please, chose a formula that fits with your application !