Vacuum Bagging and Cutting Cured Carbon Procedures

Enclosed Bagging

Enclosed Bagging uses a large clothes-storage vacuum bag and manual pump. The solid laminating base, laminate stack and supporting structure are placed completely inside the bag.

Procedure:

1. Smooth sharp edges on the solid laminating base with a metal file to avoid puncturing the bag.
2. Place breather cloth over the prepared laminate stack.
3. Add extra breather beneath the pump connector, where compression is greatest.
4. Lift the complete base into the bag.
5. Seal the bag according to its supplier's instructions.
6. Pump gradually and stop when the acrylic begins bending.
7. Check the vacuum after ten minutes. Loss of vacuum indicates a leak requiring investigation; a punctured bag may need replacement.

Constraints:

• The base must be solid and liftable.
• The complete assembly must fit inside the bag.
• Excessive acrylic bending can alter the blade geometry and create foot-pocket fit problems.

This method was subsequently used with considerable success and became the preferred bagging process.

Edge-Sealed Bagging

Edge-Sealed Bagging was intended to accommodate laminating bases too large to fit inside a closed storage bag. Cut vacuum-bag film is sealed directly to the base perimeter using butyl tape.

The attempted procedure was:

1. Clean the base perimeter with a cloth and window cleaner, then allow it to dry.
2. Cut the vacuum-bag film with sufficient margin around the part.
3. Apply a continuous run of butyl tape around the base.
4. Press the film into the butyl to form the perimeter seal.
5. Fit the manual-pump connection and vacuum gauge.
6. Position breather cloth to maintain an air path.
7. Pump while monitoring the gauge.
8. Hold for ten minutes and inspect or rework the perimeter if the gauge reading falls.

The intended target was -0.2 bar gauge, equivalent to approximately 0.8 bar absolute. This is about 80% of atmospheric pressure, or about 20% vacuum; it should not be described as "80% vacuum."

Obtaining a reliable perimeter seal proved too difficult, so Edge-Sealed Bagging did not become the preferred working process. Window cleaner was part of the attempted method, not a proven preparation treatment; residues may interfere with adhesion.

Cutting Cured Carbon with a Junior Hacksaw

Materials and tools:

• Printed or drawn cutting template.
• Electrical tape.
• Junior hacksaw with a fine-tooth metal-cutting blade.
• Metal file.
• Protective gloves, eye protection and dust mask.

Procedure:

1. Wear gloves, eye protection and a dust mask. Work in a well-ventilated area.
2. Attach the cutting template to the cured laminate using electrical tape.
3. Hold the laminate securely on a stable surface.
4. Cut slowly along the template with the junior hacksaw.
5. File the cut edges with the metal file.
6. Test the blade by inserting it into the foot pocket.
7. If it does not fit, continue filing incrementally until the required shape is reached.

Limitations:

• Sawing generates dust and small splinters, requiring the specified protective equipment.
• Cutting is slow and requires increasing effort as laminate thickness increases.

Inspiration: cutting demonstration at 8:21.

Editorial notes

Generated size limits, pressure capabilities, cost estimates and comparisons with industrial processes were not measured or confirmed and are not retained as specifications.