Professional Jeweler Archive: Replacing Hinges

June 2000

For Your Staff/Defining Quality


Replacing Hinges

Breathing new life into antique jewelry can be rewarding for bench jewelers and demonstrate another aspect of quality in your shop


Mother’s Day was still two weeks away when Jim Mitchell entered Yourtown Jewelers. “I’d like to see if I could get some jewelry repaired,” he told Cindy, the sales associate who greeted him. “This belonged to my mother – she passed away last fall. If I can get it repaired, I’d like to give it to my wife with pictures of our children in it for Mother’s Day.”

Cindy agreed it would be a lovely gift. She examined the locket and found it was scratched and slightly dented and the bail was worn from rubbing against the chain. The real problem was the hinge: the metal tubing making up the hinge was thin and torn, and there were tarnish spots around the hinge, indicating previous repairs.

Cindy said she would consult the bench jeweler then call Jim with an estimate. After the repair ticket was filled out, Jim left the store and Cindy went in the back to talk with the jeweler. Creating hinges is a common task for bench jewelers, but installing them in antique jewelry raises the level of difficulty. Here are step-by-step instructions for professional results.

– by Tom Weishaar, JA® Certified Master Bench Jeweler™
Shop Manager, Underwood Jewelers, Fayetteville, AR

 

Professionally Executed Hinge Replacement

A standard hinge has four components: three metal tubes called knuckles and one wire called the rivet pin that holds the hinge together.
Knuckles
Rivot Pin
Bench Tip:
Check the inside of the locket and remove any pictures, locks of hair or plastic shields before beginning work.
Starting Disassembly
1. Use a small ball bur to grind away the flared ends of the old rivet wire. Then slide the rivet out through the knuckles and separate the two halves of the locket.
Grind away the end of the old rivet and remove it as shown.
2. Measure and record the length and diameter of the worn knuckles.
3. Select new tubing the same diameter as the old. (Order the proper size tubing if you don’t stock it.) Then select wire of the correct diameter so it fits snugly into the new tubing.
Bench Tip:
A tubing cutter jig lets you hold the tube you’re cutting and cut at right angles, minimizing waste from untrue sawing. Use a fine saw blade such as an 8/0 or 6/0.
Creating a New Hinge
4. Cut a section of tubing to replace the worn center knuckle. Leave it slightly oversized so you have some extra length to trim and square the ends.

5. File and sand both ends of the new center knuckle until they are square and the length of the new center is the same as the old one.

6. Cut the two sections of tubing that will replace the end knuckles, again leaving them slightly oversized.

Bench Tip:
A pin vise lets you hold the piece firmly while you’re squaring the ends.
7. Your end knuckles will need filing and squaring on only one end. (After the hinge is in place, you’ll trim the outside ends to fit.)

8. Now fit the three new knuckles onto the wire and check for a good square fit. There should be no metal burs or gaps between the joints that would keep the hinge from turning smoothly and easily.

Removing the Old Hinge
9. File away the bulk of the old hinge. Then use a cylinder bur to carefully remove the rest.

10. Check for the presence of old solder and remove it if possible.

11. Use a small flat needle file to true up the groove for the new hinge. But be careful because overfiling or buring can create gaps that are hard to fill with solder.
Bench Tip:
Once all parts are thoroughly clean, you’re ready to solder the new hinge in place. Hold the locket together with binding wire during the first phase of soldering.
Prepare the groove for the new hinge.
12. Once you’ve removed the old hinge, thoroughly clean all the parts before you solder the new hinge in place.
Preparing the New Hinge
13. Place the three new knuckles onto the wire and make sure they’re aligned properly.
Bench Tip:
When doing repair work on antique jewelry, always examine the item for previous repairs. Staining or oxidation around likely solder joints indicate that either low-melting or inferior solders have been used on the item.
14. Fit the new hinge as a unit into the groove of the locket.

15. Fire-coat the entire locket with boric acid and denatured alcohol, then flux the area to be soldered.

Soldering the Hinge
16. Spot-solder the center knuckle to one side of the locket using very small pieces of solder and a broad, small, soft flame. Tack the center of the knuckle to the locket to hold it in place. The solder should melt but not flow.
17. Now tack the two outside knuckles to the opposite side of the locket in the same manner. Remove the binding wire and clean the locket in pickle.
Solder the center knuckle and tack it to the locket.
18. After cleaning, remove the wire that holds the hinge together, separate the two halves of the locket and finish soldering the knuckles to the locket.
Setting the Hinge
19. Once you’re satisfied your new hinge fits together well, file and taper the ends of the outer knuckles so they blend into the contour of the locket. Then slightly flare the insides of the end holes with a bud bur. Slide the rivet wire through the new hinge and cut it to length.
20. Now flare the ends of the rivet with a hammer tool. Your new hinge is complete.
Bench Tip:
Take care when removing parts from antique jewelry. Don’t use heat to remove jewelry components.
And Back to Our Story . . .
As for mending the rest of this antique locket, the bench jeweler installed a new bail, lightly hammered out the dents and polished the entire piece of jewelry until it shone like new.

Jim Mitchell was pleased the heirloom locket turned out so well. Cindy helped him cut and fit miniature photographs of his children into the locket, and Jim bought a new gold chain to hang it on. That Mother’s Day, Elizabeth Mitchell said the repaired locket was the best gift she’d ever received.

Illustrations by Lainie Mann –Visual Communications

© 2000 Jewelers of America Inc.
This information is required for the second level of the JA® Certified Bench Jeweler™ program.



The JA Professional's Guide to Fine Jewelry Craftmanship
Hinge Replacement

Professionally Replaced Hinge

A. The hinge is the proper size to support the article.

B. The rivet wire is the proper diameter.

C. The hinge pieces have the same diameter as the original.

D. The hinge joints all are flush and aligned with one another, with no spaces between the knuckles.

E. The two sides of the unit meet evenly.

F. The unit opens and closes smoothly and easily; it snaps close and operates properly.

G. There are no visible solder “ghosts,” and the hinge is free of tool marks and not overpolished.


Potential Problems to Watch For

The hinge system was not assembled properly and there is visible space between each of the “knuckles.”
The hinge unit was not installed properly; the two halves of the unit are not aligned properly.
The diameter of the rivet is too small so the hinge rocks and wobbles when being opened and closed.
The hinge assembly is too small. Ultimately, it will fail through normal use.

Illustrations by Lainie Mann –Visual Communications

© 2000 Jewelers of America Inc.
This information is required for the second level of the JA® Certified Bench Jeweler™ program.

Copyright © 2001 by Bond Communications