I picked up the vinegar, sodium bicarbonate and salt to proceed on my deoxidation treatment of the light panel parts. In the afternoon I made a batch of each solution - vinegar/salt and bicarb - then tested on a few lights and holders.
|lamps and holders soaking in salt and vinegar solution to remove corrosion|
|Sodium Bicarbonate solution to neutralize acid from first dip|
I have more than 100 bulbs still to pass through the baths. Removing them from the SCR board pins is a time consuming and careful process, which means I will likely spend much of today working through all the light holders, deoxidizing them and readying them for reinsertion.
Once they are all clean and any failed bulbs replaced, I have to carefully insert them on the SCR board pins. The assembly sequence for the light pedestal requires all bulb holders attached to the boards, before I swing each board into place and carefully work every lamp holder into the honeycomb cell where it belongs. Reinserting lamps will be a task for tomorrow, while the front panel is glued and sets in place on the front of the display.
Quite a few bulb holders are wedged onto the SCR board pins by the corrosion affecting both. It takes some serious work to get each such bulb loose. I lost a few bulbs which broke off at the glass envelope, but most are working out okay. Just to be safe, I ordered 48 bulbs which are electrically identical but physically smaller, which will serve in a pinch as a substitute in the bulb holder.
|Replacement mini bulb at top, same light emission and electrical characteristics as bottom bulb|
|Surface of honeycomb that bonds with horizontal plastic bar|
|Side of honeycomb which bonds with vertical plastic bars inside metal case|
|Side of honeycomb which bonds with adjacent honeycomb segment|
|Fast set acrylic glue to repair front light panel|
|Repaired front panel with honeycomb segment glued back into place|
I am also thinking of aids I can use to make the final assembly job easier. One of the problems is having six layers of PCBs on each side which need to be swung out of the way, so that only one at a time is being manipulated into position. I think I can make use of rubber bands to hold all the others out of play until needed. I have to find a good set of anchor points for the far end of each rubber band.