NetComposites

Connecting you to the composites industry

Advertisement

Wet/Hand Lay-up

  • Thursday, 24th January 2019
  • 0 comments
  • Reading time: about 2 minutes

Description 

Resins are impregnated by hand into fibres which are in the form of woven, knitted, stitched or bonded fabrics. This is usually accomplished by rollers or brushes, with an increasing use of nip-roller type impregnators for forcing resin into the fabrics by means of rotating rollers and a bath of resin. Laminates are left to cure under standard atmospheric conditions

Materials Options

Resins: Any, e.g. epoxy, polyester, vinylester, phenolic. 
Fibres: Any, although heavy aramid fabrics can be hard to wet-out by hand. 
Cores: Any.

Main Advantages

  1. Widely used for many years. 
  2. Simple principles to teach. 
  3. Low cost tooling, if room-temperature cure resins are used. 
  4. Wide choice of suppliers and material types. 
  5. Higher fibre contents, and longer fibres than with spray lay-up.

Main Disadvantages

  1. Resin mixing, laminate resin contents, and laminate quality are very dependent on the skills of laminators. Low resin content laminates cannot usually be achieved without the incorporation of excessive quantities of voids. 
  2. Health and safety considerations of resins. The lower molecular weights of hand lay-up resins generally means that they have the potential to be more harmful than higher molecular weight products. The lower viscosity of the resins also means that they have an increased tendency to penetrate clothing etc. 
  3. Limiting airborne styrene concentrations to legislated levels from polyesters and vinylesters is becoming increasingly hard without expensive extraction systems. 
  4. Resins need to be low in viscosity to be workable by hand. This generally compromises their mechanical/thermal properties due to the need for high diluent/styrene levels.

Typical Applications

Standard wind-turbine blades, production boats, architectural mouldings.

Published courtesy of David Cripps, Gurit

http://www.gurit.com


Share this article


Continue to Vacuum Bagging Back to Spray Lay-up

Comments (0)

Sign in or create an account to join in the discussion.

Leave your comment

Advertisement

Upcoming Events

Advertisement

Advertisement

Advertisement

Follow us
Subscribe to our email newsletter

Subscribe to receive our weekly round-up of all the industry's latest news, jobs, events and more!

We'll always keep your personal details secure and will never share them with third parties for marketing purposes. You can unsubscribe at any time. For further details on how we may use your data, please visit our Privacy Policy.