To repair, I first removed the backglass and the backbox insert. The insert is held in by a series of machine screws on each side of the panel. Then I carefully set the insert aside .
|On Beam broken head|
With the backbox insert out, it's a good time to check all the counters, relays and stepper units since it's easier to work on them out of the head. Also, once the head is glued up, it needs time to cure so it's a good thing to pass the time working on the game and checking things over ;-)
|On Beam backbox insert|
|Cleaning a stepper unit disc|
One thing to keep in mind is that Bally cabinets of that era use very few fasteners, the cabinets mostly hold with tongued, grooved and mitred joints and glue. So once a piece is broken, like in the case of my On Beam, the repaired re glued joint will never have the strength it had when it was intact. However, the game is cactus if I don't do anything to repair the cabinet and give this rare game a new life. The head does have a couple of factory wooden corners to strengthen the joint so it helps a bit to take some stress off the repaired joint.
I use Lepage carpenters yellow glue for the glue job. Once glue is applied and the pieces stuck together. I use carpenters clamps to hold the pieces tight while the glue cures. It's also good practice to verify squareness of the backbox before setting the piece to dry definitely. I put some stretch wrap on the floor under the workpiece to avoid messing up my kitchen floor with glue. A clean and damp cloth can be used on the workpiece to remove the excess glue and runs.
|Re inserting Insert|
Once the glue has cured for 36 to 48 hours, the insert can be reinstalled. A good trick I found to avoid damaging factory information cards is to fold pieces of cardstock on the sides over the info cards before carefully re-installing the insert.