grp repairs to caravan?

Only a guess
Can only tell you how I did a front box on a caravan I had some yrs ago sold it since.
Materials:
Car dent repair paste
1 sheet medium carborundum paper [Wet and dry]
1 sheet fine carborundum paper [Wet and dry
Spray can of undercoat
Spray can of finish coat.
Good muscles you have to prepare ths surface.
Once surface cleaned of any dirt greas etc
Rub down repair area. Fill cracks with paste scraping off surplus.
When hardened rub down with wet and dry medium used wet until flat.

Ensure the surface is dry and you'r happy with finish then spray with undercoat 2 - 3 coats lightly rubbing each coat down with medium wet and dry used wet.
Ensure each layer is dry before spraying subesquent layers.
Finally finish coat 3 coats each rubbed down.
Then when perfectly dry again, spray with 3 coats of laquer. Mean while wait for more replies their may be an easier method although I found this ok but time consuming.

Bob
January 2010