Vacuum Bagging (& More) Kits

Vacuum bagging process

• Mask off the perimeter of the mold flange with a masking tape or flash tape. This keeps mold release from being applied to the area where the vacuum bag sealant tape will go. 
• Apply 3-4 coats MOLD-RELEASE-TR to mold surface and buff off after each coat dries (5-10 minutes) Note: Paste wax can be followed up by an application of Poly Vinyl Alcohol (PVA) barrier film RWC does not carry it. Epoxy is very aggressive and PVA ensures that the part will release as it creates a vinyl barrier between the mold and the part (not to be used in prepreg applications). Chemlease mold release systems should always be used for prepreg processing.
• Remove perimeter tape and replace with vacuum sealant tape. Do not remove the brown backing paper yet.
• Cut Fabric/Material with desired shears.
• Weigh or measure and mix desired amount of resin and hardener in containers. 
• Using a brush or ROLLER-FRAME with ROLLER-COVER, spread on a layer of the resin onto the mold surface.
• Apply Fabric/Material and work into resin with FLEX-SPREADER OR SLOTTED-ROLLER. Note: That you will not want to apply alot of pressure when using the FLEX-SPREADER or SLOTTED-ROLLER. If you push to hard you can remove resin from the fabric.
• Add more resin as necessary and repeat steps 7 & 8 until all layers are wetted out, air removed and there is no bridging (fabric not touching the mold surface or previous layers). Note: When a part is vacuum bagged, excess resin will be squeezed out of the laminate, so it is not necessary to have a really wet laminate before bagging. 
• Use FLEX-SPREADER to remove excess resin from laminate.
• Apply Peel Ply to the laminate. This layer does not need to be wetted out with resin. Ensure that there are no wrinkles and that the material lays completely flat on the surface. Cut as necessary over mold details to ensure that it lays flat. Ensure that there is no bridging of the peel ply.
• Apply Release Film over the peel ply. Secure in place with 8992-200 the flash tape where necessary. Ensure that there is no bridging of the release film.
• Apply Bleeder cloth/Breather on top of the release film. You can put down a second layer if you feel that there is too much resin in the laminate. This material performs a double duty by soaking up excess resin (bleeder) and evenly distributing vacuum across the entire laminate (breather). If there is too much resin in the cloth, vacuum pressure will not be evenly applied.
• Position base of VACFITTING-050 away from the laminate where necessary. Place an extra layer or two of the breather cloth under the vacuum fitting base.
• Apply Vacuum Bagging film over the laminate, lightly sealing the edge of it to the vacuum sealant tape as you work, so you can easily remove and re-position it, if necessary. Wait until the bag is fully in place before pushing really hard on the sealant tape. Create pleats in the bag with sealant tape if you need a larger bag to position it over mold contours to prevent bridging. Place bag pleats in depressed areas to also prevent bridging. Ensure that there are no gaps between the bag and the sealant tape or air will leak into the bag.
• Cut a small hole or cross section in the bag where the upper portion of the VACFITTING-050 will attach to the base.
• Attach one end of the desired amount of AIRHOSE-0500 vacuum hose to the vacuum fitting. Attach the other end to the vacuum pump.
• Turn on the vacuum pump and slowly remove the air from the bag, using the HOSE-CLAMP as necessary to stop the air-removal process to allow you to work the bag over the part to prevent bridging.
• Apply full pressure once you are satisfied with the placement of the bag and check for air leaks. Once there are no air leaks allow the part to remain under full vacuum until the laminate has fully hardened according to the resin system’s manufacturer specifications. With West systems and Super Sap systems you can expect 8-10 hours. The vacuum pump that we sell has a duty cycle of about 10 hours. After 10 hours you will need to replace the oil.
• Once fully cured, remove the vacuum bagging materials and discard them, making sure that you do not throw away the vacuum fitting. Use the plastic wedge to remove the part from the mold. You may need the assistance of compressed air to remove the part from the mold.