Advice with crack/fracture repair Options

[GuitarC]

Just attended 2nd class of a "Beginning Cabochon" course I am taking and I am learning a lot . I was working on the CabKing 280 wheel doming my 30-40mm oval jasper cab and class was ending so dried off stone and checked a small inclusion I was keeping my eye on and it is now a thin fracture line . It starts at the edge and runs almost parallel to the edge of the stone 2-3mm in from the edge before ending at the edge an inch away from where it starts. It looks like that piece could completely crack off the stone if I continue to work it and the cab still needs some doming before moving on to 600 etc. I told the instructor and asked her if a 2 part epoxy could be used and then continue shaping/polishing etc and she said I could try that next week or I could pick another slab next week and start over. Starting over is no big deal because I know I can get back to where I am in one class. I have already decided that I am going start a new cab next week.

I might make a smaller piece from this cracked cab, maybe a guitar pick!


I have 2 questions:

1. If I choose to make a guitar pick and trim it down to guitar pick size (cutting off the fractured portion), I need to thin the piece since it is thin for a cabochon but too thick to be a guitar pick even for me. I like thicker picks 2-3mm range but the cab is now 5mm. Do I thin it on a flat lap or some other method?

2. I probably will not attempt to repair the fracture but want to know the best ways to repair cracks and fractures because I am sure I will encounter them in the future. I have not worked with stone prior to last week but think a few methods of repair could work. I would think that heating a stone opens a fracture and would also further liquify an epoxy upon contact and allow it to fully seep in. Is heating a stone to repair it this way a good idea? What type of epoxy is good for use on stone? Another method is to fully submerge the piece in heated liquid plastic to let it fill a crack or fracture. These are just theories based on working with other materials so I do not know how well they would work on stone. Any advice, tips, experiences?

Thanks!

[Denise]

Your doing great GuitarC! Keep up the good work, and satisfaction will come in no time.
Did you dop with wax, or just use superglue?

Hi Voltaire, and welcome to the CP forums.