Repairing a Vintage Bakelite Doorbell Cover
This much loved door chime case had fallen on hard times. Literally. One too many tumbles to the hardwood floor had rendered the case unsightly and it no longer stayed fixed to the mechanism. The chime, a 1950 long bell Mell-O-Chime was still mechanically serviceable although the condition of the case made the chime was unsuitable for the restored home.
This chime had graced the same home for generations. The current occupants were embarking on a complete home renovation with the goal of preserving as much as possible of the was home’s original period charm. They turned to the skilled craftsmen at ElectraChime, the Doorbell Museum’s sponsor, for help. The mechanism was cleaned and made electrically sound. The case presented more of a challenge. Large pieces of the top of the case were missing and a long crack further weakened the structural integrity. Another piece of the fluted side was missing.
Repairing Bakelite with Fiberglass Filler
The restoration employed a technique perfected for repairing damaged bakelite radio cases. The rough edges around the damaged areas are cleaned up and replaced with structural reinforcement and fiberglass filler.
Sheet metal is cut and shaped to the inside contours of the chime taking care to make sure it will not interfere with the hanging bells or operation of the mechanism. The sheet metal is secured to the structurally sound areas of the case using self tapping screws.
Thin layers of fiberglass filler are built up to replace the missing plastic and fill in the cracks. The filler adheres to the old bakelite and the metal.
Sculpting the original contours
Using the remaining original 
contours as a visual template, the filler is carefully shaped and then sanded to match the original shape. The entire case is sanded for finishing.
This chime case was originally cast in brown bakelite with a painted finish, so an enamel re-spray is appropriate.
Finished Restored Mell-O-Chime
Generally, the Doorbell Museum advocates an original finish and patina whenever possible. However there is no hard and fast rule and the owners preferences must be taken into account.
As extensive restoration and a new finish was required for this case, the owner agreed refinished bells were appropriate. The bells were radially brush finished on a lathe and then clear coated with lacquer to protect the luster. This Mell-O-Chime is ready for another 60 years or more of service.