The Vacuum Infusion Process (VIP) is a technique that uses vacuum pressure to drive resin into a laminate. Materials are laid dry into the mould and the vacuum is applied before resin is introduced. Once a complete vacuum is achieved, resin is literally sucked into the laminate via carefully placed tubing. This process is aided by an assortment of supplies and materials.
- Basfiber® Fabrics.
- Vacuum Pump.
- Sealing Tape.
|Vacuum infusion Application Process|
|Basalt Fiber Tech Vacuum infusion Application Process©2015 - Designed by Lucas Sant'Anna|
- A Mould is placed over a Plastic Layers, using a sealing tape you cover the edges. In the next step Basfiber® Fabrics will be applied over the mould. The amount of layers of fabrics depends on final product specifications.
- Basfiber® Fabrics layer is placed over the mould. A second plastic layer is applied. Pressurizing the tape on the edges of the plastic, the mould should be completely sealed.
- Vacuum Pump is attached to the plastic, a resin is also connected. Both hoses must be connected to the plastic providing sealed bag strong enough to pull the resin until air is removed.
- Resin Impregnation occurs when all the air is removed from the plastic bag forming a vacuum. When all bubbles are removes and the pump reaches the maximum pressure, the resin input is closed and the resin excess is removed from the mould.
- Remove from Plastic and Trim edges and make sure there is no resin bridging the line between the mould and the part. Sand this edge where necessary. Continue separation by pulling and flexing.
- The Final Product is now painted and completed with accessories. The source mould can be used again, this process is very useful to recreate parts using them as original mould substituting the original then by a lighter resin infused Basfiber® composite.
Benefits of Vacuum Infusion
Vacuum infusion provides a number of improvements over traditionally vacuum bagged parts.
These benefits include:
- Better fiber-to-resin ratio.
- Less wasted resin.
- Very consistent resin usage.
- Unlimited set-up time.
VIP offers a better fiber-to-resin ratio than vacuum bagging. A typical hand lay-up usually results in excess of 100% fabric weight by resin. Resin alone is very brittle, so any excess will actually weaken the part. Vacuum bagging can reduce this number significantly; however, it is still not ideal and can lead to additional problems.
While vacuum bagging certainly improves on the hand lay-up, there is still a hand lay-up involved. Because of this, the laminate will always begin in an over-saturated state. Vacuum pressure will remove much of the excess resin, but the amount removed still depends on a variety of variables including reinforcement, resin, time factors, and others.
Vacuum infusion takes a different approach, in that a vacuum is drawn while the materials are still dry. From that point, resin is infused using vacuum pressure. Rather than starting with excess and drawing resin out, VIP starts with none and pushes resin in. Ideally, any excess resin that is introduced will eventually be sucked out into the vacuum line. As a result, only the minimum amount of resin is introduced. This lowers weight, increases strength, and maximizes the properties of fiber and resin. Parts constructed using VIP can approach PrePreg levels of resin content.
Due to the nature of VIP, resin usage becomes very predictable. While a standard lay-up varies in resin content due to the human variable, VIP is remarkably consistent. Even when creating a large product, resin usage will be predictably similar upon repeated attempts. This results in less wasted resin, and more importantly, less wasted money.
Vacuum infusion provides another valuable benefit: time. A frequent problem that can arise in vacuum bagging is the time factor. Many resins have a pot-life of about 30 minutes, though there are certainly some (such as our System 2000 Epoxy) that offer work times of up to 2 hours. Even so, that time limit is extremely critical in vacuum bagging applications. Large projects can easily approach the 2 hour mark, and even small, seemingly simple projects can quickly turn frantic when a pesky leak in the vacuum seal cannot be found. Also, depending on when the bag is applied, the amount of resin removed can vary from part to part.
Vacuum infusion, however, offers unlimited set-up time. Because the vacuum is applied while reinforcements are still dry, there is no resin clock to work against. After the bag is applied, leaks can be patiently sought out. If something is not sitting properly, simply release vacuum and readjust. No time constraints are introduced until it is decided that it is time to infuse the resin. Until that moment, changes can be made again and again.
Finally, vacuum infusion is a much cleaner process. There are no brushes or rollers, and therefore no splashing or spattering. No one will be required to hover over an open mould, saturating a laminate by hand, trying not to drip on himself. In addition, there are less resin fumes to contend with. Because the only fumes radiate from the resin reservoir, they are somewhat containable. VIP provides a cleaner, safer, and friendlier work environment, though it is still important to work in a well ventilated area and wear a respirator and other appropriate safety equipment.