Vacuum injection | How do you laminate a sheet by vacuum injection?

Polyestershoppen.com is a wholesale business in epoxy and number one specialist in composite materials. One of our specialties is vacuum and vacuum injection (vacuum infusion). We offer a wide range of vacuum materials and necessary accessories. For example, in the vacuum materials category you will find everything you need to apply vacuum injection professionally.

In this article, we explain how to laminate a sheet with vacuum injection. This is a clean production method that produces a high-quality product. Led by our vacuum specialist Herman, we take you through the process step by step. Do you have questions about the vacuum injection technique or about the materials used? Please feel free to contact us, our specialists will be happy to advise you!

What is vacuum injection?

Vacuum injection is a laminating technique in which the fibres are placed dry in the mould. These fibres are covered by a vacuum foil (vacuum bag). By pumping the air from under the vacuum bag, a vacuum is created that sucks resins, such as epoxy resin or polyester resin, into the fibre.

What are the advantages of vacuum injection?

Working with the vacuum injection technique has the following advantages:

  • Clean process. After all, a quantity of resin is only produced at the last moment, which then does not have to be processed manually.
  • High quality laminate.
  • No pinholes.
  • No air bubbles.
  • Low resin consumption.
  • High fibre to volume ratio.
  • No laminating experience required.
  • Work can be checked step by step in advance.

What do you need for vacuum injection?

You can easily order all the necessary materials for vacuum injection at Polyestershoppen.nl. You need the following products to apply the vacuum injection technique:

Tip: want to try vacuum injection on a small scale? With the resin infusion starter kit, you have everything you need to get started right away!

Vacuum injection manual

In the video below, specialist Herman explains how to laminate a sheet using vacuum injection. Below the video we have written out all the steps again for you. So you can read it back at your leisure.

Step 1. Place glass fabric, core material, tear fabric, perforated foil and flow mesh on top of each other

You start by laying out the desired fibre package (glass fabric is used for this in the video). Place the glass fabric over the mould with the core material (3D Core) you want to use on it. The fibres and core material can be fixed with spray adhesive. Use only a minimal amount of spray adhesive.

After laying the desired fibres and core materials, lay the tear away fabric, perforated film and flow-through mesh on top of each other.

Step 2. Connect the MTI hose to the vacuum hose

Connect the MTI hose airtight to the vacuum hose. To do this, push the vacuum hose into the MTI hose until it fits neatly against the hose. Then wrap a piece of sealant tape around this.

To feed the hose through the vacuum bag leak-free, apply an extra piece of sealant tape.

Step 3. Connect the resin supply line and the spiral hose

Press the resin supply line into the spiral hose and again apply a piece of sealant tape to the part where it exits through the bag. Tape the spiral hose on the other side so it won't shift when vacuum is applied to the bag.

Step 4. Apply the vacuum bag

You are now going to apply the vacuum bag to the mould. In the video, we have allready pre-treated the bag by sticking the sealant tape on the edges. This makes it a lot easier to put down the vacuum bag. Make a fold in the vacuum bag at the location of the pipes. This way you can be sure that you will have enough foil for this later. 

After the vacuum bag is taped, check whether it is connected to the mould properly and airtight everywhere. The folds and corners where sealant tape overlaps are especially important points of attention.

Step 5. Turn on the vacuum pump 

You have now made all the preparations and you can turn on the vacuum pump to check the leak tightness. When you turn on the pump, you will see that it slowly creates a vacuum. Make sure that the pipes are neatly surrounded by vacuum foil and that the product remains as flat as possible.

Step 6. Run the resin through the pipes

Now let the mixed resin run through the pipes. The resin slowly spreads over the surface. Once completed, turn off the resin tap and then allow the epoxy to cure for approximately 72 hours. After this you can remove all auxiliary materials. The result is a stiff and lightweight panel without air bubbles.

More information about vacuum injection?

Would you like more information or tips about vacuum techniques? Our specialists are happy to advise you. You can reach us on working days by telepphoneemailWhatsApp or via the live chat function on our website.

You can easily order all vacuum products at Polyestershoppen.com. Are all products in stock and are you ordering before 5:00 PM Dutch time? Your order will then be shipped the same day.

Product advisor
  • Expert advice
  • Superfast delivery with PostNL
  • Pay after delivery

Products used in this article

Product 1 of the 1

Do you have a question?

Do you have a specific question? Call one of our specialists for free advice +3185 0220090