Diary

Repair of early Flexifoil Aaron Hadlow Pro 

DAMAGE ASSESSMENT

As can be seen:

1)  the PVC top layer has de-laminated at the tips.

2) The rail has been impacted fracturing the micro-balloon epoxy construction.

3) Damage to the "Dura" base at the edge.
4) An attempt at repair has been carried out.

Fortunately the carbon  on the top layer is still intact but the sand and water has
hydraulically forced the top & bottom skin away from the core. This has been
compounded by a repair using body filler, which acts as a riser or hinge on the
other structures. I will need to replace the detached core material and bond back
with carbon reinforcement under a vacuum bag. The "Duragrind" P-Tex base will
also need replacement over the de-laminated area.

Fortunately the edge delamination does not extend to far inboard
Damaged core removed and staggered cut back of each layer near the rail.

  Tips with top layer ground back.
  The damage at the tips, now obvious, probably caused the PVC top layer delamination
  due to water & sand ingress. Note: Always repair earlier rather than later!!

   Cosmetic damage to the micro balloon mix at the rail.

LAMINATE & FOAM STRUCTURAL REPAIR

The following  stepped sanded repair process (pdf document) by HEXEL
was carried out following the standard practices of sandwich core construction.

    The final cure was carried out at a reduced temperature of 90-100 C for
    12 hours in order to prevent damage to the  original core material.

        Herex foam stepped and shaped to fit cut out section
                   ( Use an adjustable pin profile former to get the parts to match)

        Herex bonded in place with Epoxy under Vacuum

        Herex cut back and tapered to existing carbon

        Carbon Pre-preg applied & stepped to existing carbon laminate

        Release Film applied

        Prior to breather fabric and Elastomax bagging film

        Bagged up with breather and vac'd down

        Thermostatic heater over repair area

        Removal of films after cure

BASE REPAIR

                             Base material cut away using matched template with new base material
                             obtained in 4 days !  from Tognar in USA http://www.tognar.com
                              A Black patch was used instead of clear as the cut out was made a feature
                             (rather than disguise, it which would have been very difficult to colour match)
                             Again this was stepped larger than the last removed layer in order to stagger
                             the repair & increase its strength. The repair material bonds extremely well
                             with the Epoxy adhesive. (Prior peel tests proved the bond exceeded the shear
                             strength of the material its was bonded to.)                                  

           Treated surface of UHMWPE (P-Tex)  with applied Epoxy adhesive

         Base patch in position prior to bagging

            Tip repair with carbon re-enforcement

          Vac down again to remove any trapped air bubbles & left
                               for 12 hours for epoxy adhesive to set.
                               Patch scraped down & trimmed to match original base.

PAINTWORK

       
Repaired surfaces rubbed down and treated with epoxy and  Microballoon filler.
Areas masked off & plastic primer applied and rubbed down with 1500 grit.

Pic's of board re-sprayed with "matched original" colours (Click images to enlarge)
The centre area is original the tails have been sprayed. 4 Colours needed!

Base showing patched area                               Top prior to rub-down & UV protection

Detail of spliced patch of P-Tex                       Re-Painted tails          

Gloss UV protective coat applied.(International Perfection,   2-pack poly-urethane)

Anti-slip additive added to top coat, masked up & applied to grip areas.

    Decals applied

READY TO SHIP