• Corvette to Mass-Produce CFRP Bonnets
  • Corvette to Mass-Produce CFRP Bonnets
  • Corvette to Mass-Produce CFRP Bonnets
  • Corvette to Mass-Produce CFRP Bonnets

Thanks Thanks:  0
Likes Likes:  0
Dislikes Dislikes:  0
Results 1 to 2 of 2
  1. #1
    Site Administrator Rob's Avatar
    Join Date
    Sep 2000
    "Manchestah" NH
    Post Thanks / Like

    Default Corvette to Mass-Produce CFRP Bonnets

    Corvette to Mass-Produce CFRP Bonnets

    According to Corvette, the ZR1 is set to be the first mass-produced car with an all-CFRP bonnet, with between 1,500 Ė 2,000 units sold annually.

    This has meant that Corvette has had to refine their production process, ensuring that they can deliver one completed bonnet within a 60-minute production process.

    During development, Plasan investigated a variety of different layup, kit and bagging methods to find a process combination that yielded the best appearance and performance within the shortest processing time.

    Bonnet production begins with kit cutting. Rolls of carbon prepreg are loaded onto a cutting table supplied by Eastman Machine and cut into an individual kit of pieces needed to produce a complete hood (separate sets for outer and inner).

    Because Plasan produces a number of CFRP parts for the ZR1, managing and organizing kits is a major aspect of production. Kit components are hand-layed into single-sided, female steel tools.

    Layup technicians visually inspect prepregs and use special techniques to position plies precisely on the first try to minimize pulling or stretching of plies, which could distort the appearance, explains Lars Severance, Plasanís manufacturing engineer.

    When layup is complete, the parts are vacuum bagged and moved to one of Plasanís four production-size autoclaves where, using ACGís fast-cure epoxy, they cure in about 10 minutes.

    Because of their complex plan-view sweeps, demoulded parts are edge-machined on an automated, high-speed, 5-axis robotic router, which is capable of cutting very tight radii and negotiating complex slope changes at high spindle loads.

    Next, the hood inner and outer panels are prepped for adhesive application and placed in a bonding cell. Here, they are robotically bonded around the perimeter edges using a two-part structural urethane specially formulated by Ashland Inc. to cure quickly, survive paint-bake oven temperatures and exhibit the high strength necessary to prevent debonding of inner and outer panels under the stresses of high-speed operating conditions.

    Each hood is 100-percent hand finished. Technicians sand the outers and hand-polish the inners. Then, the inner panel is masked, the assembly is passed through Plasanís primer booth and, when cured, the primed hoods are shipped to Creative Liquid Coatings (Ft. Wayne, Ind.) to be painted.

    Just before final quality-control inspection, the polycarbonate window is joined to the hood assembly. To accommodate the coefficient of thermal expansion (CTE) mismatch between the CFRP and the PC, technicians use a special compliant shear/ductile urethane adhesive, also provided by Ashland.

    Completed units are shipped to GMís Bowling Green, Ky., assembly plant for installation on ZR1s.

    Publication Date: 21/08/2009

    WWW Link: Eastman
    Rob Loszewski, Owner & Site Administrator
    Corvette Action Center
    Cadillac V-Net
    Cadillac XLR Net
    The Meadery
    Torque Network
    NCRS Member #27792
    "Let your plans be dark and impenetrable as night, and when you move, fall like a thunderbolt." - Sun Tzu
    1990 Chevrolet Corvette ZR-1 , 350 Stock ZF 6-speed. Stock Bright Red

  2. #2
    Moderator catbert's Avatar
    Join Date
    Aug 2004
    Tobacco Road, NC
    Post Thanks / Like


    Bonnet???????????? I say old chap - we call them hoods in the Colonies.

Similar Threads

  1. Dual Mass Flywheel Problem?
    By 97vette in forum C4 Technical and Performance
    Replies: 22
    Last Post: 03-03-10, 05:03 PM
  2. Lightening Flywheels - An Exercise In Rotational Dynamics
    By Ken in forum General Automotive Discussion
    Replies: 2
    Last Post: 01-07-05, 04:42 PM
  3. Single mass flywheel = vibration in the shifter?
    By Skant in forum C4 Technical and Performance
    Replies: 2
    Last Post: 08-13-04, 11:46 PM
  4. Does Granatelli Motorsports Mass Air Flow Sensor really produce 10-15 RWHP??
    By Vette96CE in forum C4 Technical and Performance
    Replies: 4
    Last Post: 05-19-03, 02:50 PM
  5. Another mass air flow ques. for C-5/4 spec.
    By Da Hawaiian Punch in forum C5 Technical and Performance
    Replies: 1
    Last Post: 09-17-02, 06:46 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts