Water based release agents offer many advantages compared to traditional solvent ones and mould release waxes. However, because of their application, which differs from traditional release agents, many companies are still hesitant to use them. Over the last few years, implementing mould release systems in different industries and processes, we have realised that the biggest obstacle for our customers was to learn on how properly apply them. Based on this experience, we would like to share in this post everything you need to know on how correctly apply water based release agents.
The 5 steps at a glance:
- Clean and seal the mould — remove any residue that creates mechanical anchor points, then seal to close the mould surface micropores.
- Use the right spray gun — water has high surface tension, so the nozzle must be small enough to break the droplet.
- Keep a constant speed — never hold the gun in one spot, and repeat the same movement every time so no area is left uncovered.
- Start with more, then reduce — apply more enough release agent at first and cut back as your operators gain experience.
- Wipe off the excess — remove any surplus with a piece of paper; too much release agent makes demoulding harder, not easier.
Step 1: Proper mould preparation
For an effective demoulding process, prior preparation of the mould is essential. First of all, the mould must be perfectly clean. We must avoid mechanical anchor points on the mould surface due to improper cleaning. It is at these points that the final part usually sticks during demoulding. After cleaning the mould, a sealant will help us to close the micropores, considerably increasing the performance of our water based release agent and improving demoulding.
Step 2: Use an appropriate application equipment
As funny as it sounds, water is one of the worst ‘wetters’ there is. Due to its chemical structure (surface tension), its droplets do not easily penetrate most surfaces. For this reason, the key point for a correct application of water based release agents is breaking the water droplet of our release agent. To do this (breaking the water drop), we absolutely need a spray gun with a sufficiently small nozzle that guarantees both a right amount of release agent passage at the right pressure. During the release agent application, we should create a kind of mist on the mould. We must always avoid pouring drops on the mould surface.
Step 3: Keep a constant spray gun speed
When applying water based release agents, avoid holding the spray gun in a particular place. Adjust the application speed to avoid release agent build-up areas on the mould surface. If any doubt, watch the step 2 video. Try to repeat the same movement every single application so that you never leave any mould area uncovered.
Step 4: Apply more at the start, then reduce
As any learning process takes time, do not be afraid to initially apply more release agent than usual just to ensure a good demoulding. Gradually, depending on the ease of demoulding the part and the experience of the operators, increase demoulding cycles or reduce the amount of release agent applied. Compared to traditional release agents, the amount of water based release agent we apply is much smaller. This means that this extra amount we can apply at the beginning will not foul the mould, nor will it cause a transfer of the release agent to the final part surface.
Step 5: Always remove any excess of release agent from the mould surface
In the event that, due to carelessness or incorrect application, we apply too much release agent in a certain place of the mould (drops on the surface), we will simply remove the excess by rubbing the mould surface with a piece of paper. Although it may seem the opposite, an excess of water based release agent hinders rather than facilitates final piece demoulding.
Common mistakes when applying water-based release agents
Water based release agents offer so many advantages that more and more companies are adding them into their production processes. When implementing mould release systems for different industries and processes during last years, we have realised that the biggest obstacle for our customers was their correct application. In this short post, we wanted to share our experience and show that water based release agents application is not such a complicate science. The most common mistakes when applying this type of release agent are: failing to maintain the correct distance and speed when applying the release agent to the mould, and incorrect adjustment of the air gun nozzle.
In any case, if you need more information about water based release agents or any other products in our offer, please do not hesitate to contact us. AITANA CHEMICALS offer technical assistance and customized solutions for moulding processes in different industries.
If you want to learn more about water base release agents, we recommend you read our extensive article on this topic.
