I use the left over resin from my projects to fill Opihi Shells and I leave them on the side for when I have time to sand them down. I had time this weekend so I decided to make some pendants to give away as gifts. These are the steps I went through.
- Fill the interior of the shell with casting resin mixed with dye.
- Attach the bail with epoxy and coat the sanded resin with UV epoxy and cure it.
- Sand the exterior of the shell and flatten the bottom down with my Belt Sander with 60 grit.
- Take out the scratches with the Orbital Sander with 120 grit.
- Smooth it out with the Orbital Sander with 400 grit.
- Wet sand the entire piece with 600 grit.
- Continue wet sanding it with 1000 grit.
- Finish wet sanding with 2000 grit.
- Polish it on the buffing wheel with polishing compound.
I do not coat the exterior of the shell with anything. Some people use Mineral Oil or epoxy but I leave it natural.
I have been asked why I fill the interior with epoxy and the reason for that is that the shell gets too thin and fragile when you polish the small ones.
I am pretty hay with how they came out. As with anything some polish out better than others.