Jewelry, Gems, & Minerals/Setting wire
Here is my question. I would like to use copper and silver pins to make end loops for stone/agate pendants. What kind of epoxy or Super Glue could I use for longer lasting near-invisible bond?
Read your Bio...very interesting fellow.
Ypo should not use super glue. Generally the cement will show but of main concern it is not strong enough in your application. In certain types of joining, super glue is dandy as long as you use a type allowing you to properly position everything before the cement cures. However, in securing the end loops to stones you will have several frailures down the road and the wearer will look and see their pendant is gone and only a loop remains on the neckchain.
I recommend this epoxy cement:
Epoxy 330 by Hughes, sold on the net and in crafts stores and rock and gem shops.
This epoxy cures water clear and colorless, is designed for securing metal findings (parts) to gemstones and has a proven record of strong and long lasting cemented connections. The solvent for the cement is acetone but gentle heat on the metal part will also loosen it for removal as need-be.
Here is a good method for using the epoxy:
1. Have all parts ready and do a dry run of how you will assemble the loops to the stone. This means providing a support or clamp to hold the metal in position while the epoxy cures. The cement has no strength at first and everything must be supported in position for at least the first 45 minutes.
2. Have an old plastic baggie, piece of waxed paper or similar non-absorbent surface for mixing the two parts of the cement. Place with that a mixing, applicator tool such as a tooth pick (best with the pointed end cut off).
3. Wipe th4e metal and stone clean with alcohol to remove skin oils or other residue which might weaken the glue joint.
4. Put equal blobs of catalyst and resin each in its own place on the mixing surface. One of those is slightly thicker than the other so put out the two small blobs and let settle a minute to see more easily see how much was squeezed out. (You will not get exact equal amounts but visually close is close enough for a strong mix.)
5. Using a folding motion mix the two parts of the cement.
6. Put a small amount of cement on one or both of the parts and assemble, providing support as planned already. All can slide around and cement may run if placed on a downward direction with too much cement and that is why a planned out method of support is needed.
7.With all glued, put the applicator/mixer back onto the mixed epoxy. You can check for curing (hardening) by moving the applicator and avoid disturbing the jewelry pendants until fully hardened and ready to go.
Hints: Support may be made with modeling clay,locking tweezers of other methods you might come up with. Also, after about 30 minutes, gentle heat as from an open incandescent light bulb held close will speed the curing process greatly. At first, heat makes the cement mix very fluid and that is why I suggest allowing it to cure normally for about 30 minutes first.
(The heat is good if you want the cement to flow into a groove, etc. in some other use.)
Before starting any cementing be sure the parts have good surface contact for the cement.
Robert, the link to amazon.com is just one supplier of this epoxy. Try locally at crafts, model hobby and rock and gem shops if you want.
Normal room temp cure for 330 is about 2.5 hours. Another version named 220 is made but it has an amber color when cured and takes much longer to cure.
Best wishes with this project.
God Bless and Peace, Thomas.