[Mike Finley]

A customer called me today saying they burned a hole through their formica bathroom vanity with a candle. Can I bond new Formica over the old Formica or do you have to rip it all out and put in new substrate and then Formica on that as you would a new installation?

 

[Teetorbilt]

Mike, easy as pie.
Address the hole first, use a quick set epoxy to fill any low spots. I advise against bondo here. Sand the divot and any high spots level then sand the rest of the surface to break any gloss. Wipe with alcohol and procede like any other mica job.
I resurface mica about every other month, have two jobs lined up right now.

 

[Mike Finley]

Dat's what I figured. I was just going to fill the hole with some spackling and sand it, and the entire surface with 80 grit on an orbital, then rock on and collect a check.

 

[Floorwizard]

Don't forget to check for bubbles and loose spots.
I am sure you already know this.......

 

[Teetorbilt]

Nix the spackle. You want to maintain a solid surface which is why I advised against bondo, too soft and could bubble in the future.
I usually use 60 grit, gives plenty of 'tooth'. You may want to approach corners/radii with a sanding block or inline sander to keep things flat and square. Orbitals on small surfaces tend to produce a crown.