Fiberglass tack spray for composite assembly

[Guy Johnson]

I saw this on Facebook. Cool method to keep glass fabric in place while bagging composites. 

Tack spraying dry fiberglass with specialized adhesives (like Fibertack MT-1) 

stabilizes reinforcement layers on molds before vacuum bagging or resin infusion

. This process prevents fiber misalignment during bag placement, ensuring complex shapes remain in position. Key techniques include applying light, consistent sprays and using adhesives compatible with epoxy, polyester, or vinyl ester resins. Facebook +1

Key Aspects of Tack Spraying Before Bagging:

• Purpose: Holds dry fiberglass, carbon fiber, or core materials in place, preventing shifting or sagging, especially on vertical/complex molds.
• Adhesive Choice: Use specifically designed, non-HAP (Hazardous Air Pollutant) aerosol tackifiers (e.g., Fibertack MT-1) that do not interfere with resin infusion or laminate properties.
• Application Method: Spray a light mist over the dry reinforcement, allowing the solvent to flash off for 15–20 seconds to build tack. Avoid heavy, wet spraying to prevent resin-rich areas.
• Alternative Methods: For smaller parts, materials like rubber grip mats can be used for tacking, or simply rely on the natural tack of laminating resin on previous layers. Facebook +3

Guy 

Puffin 10M #6

[Dave Cole]

So once you get the composites tacked in  place, do you brush on resin, then bag and evacuate?  Or do something different?  

Dave

10M #26

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[Guy Johnson]

I saw some videos that show the layers put in place and then the resin applied either by brush or pouring and then the layup was rolled with a serrated aluminum roller to drive fully wet out the layup before bagging. 

Probably resin infusion is the most common use of tack spray. 

Just thought this was an interesting technique to share. 

Guy

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Subject: Re: [pearson] Fiberglass tack spray for composite assembly

 

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[Dave Cole]

I agree, It is interesting.   

Thanks for the info.

Dave

10M #26

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