Rv-12iS Stabilator tip fairing repair

[YME]

Now this is not a big repair but I have never worked with fiberglas. As you can see in the pic, I cut into the Fairing flange too far. For this repair do I just mix expoxy and add flox and build up the flange area or do I add some cloth underneath. The fairing is not attached and I have the West System 105 Resin & 205 Hardner. What is the procedure for something like this?

 

[Southern Pete]

You need some cloth otherwise it will have no strength.
Scarfe the backside to an angle of at least 15:1 (30:1 if this was a structural repair).
Lay up cloth with resin over some kind of mould.
The closer you can make the "mould" to the final shape the less sanding/filling will be required.
Get someone with experience to help, otherwise you will do the repair 2 or 3 times.
The alternative is to buy a new fairing, but this is easily repairable.