Pinball DMD Repair
The display in my Data East Star Wars machine was a bit of a dissapointment when i got it. Although it was nice and bright, it seemed to be missing the rightmost column and the bottom row of the display completely. Initially i just left this, but before long i wanted it sorted and started to investigate. I happened to be on the phone to the guys at Pinball Heaven and managed to catch them at a quiet moment (quite rare apparently!). Now i have to give these guys credit here. Phil could easily have just told me that the display was knackered and earned a very nice sale, but, no, he told me that being a Babcock display he could guarantee that there would be pins broken off where the metal pins get sandwiched between the two layers of glass.
He also said that he could get it sorted for me for a reasonable cost, but also went on to tell me how i could do it myself. Being either adventurous or stupid (not sure which) i made a mental note to look at it at the weekend, and this page bears the results. Thankfully, good results.
This is not here as a tutorial in any way. Actually i don't think i've done a desperately tidy job of this, BUT i now have a nice working display, so i'm over the moon. PLEASE don't ask for more details than can be seen here as there aren't any more to be had really, i just waded in and gave it a go. At the end of the day, the alternative was a broken display, so i had nothing to loose really. IF YOU WOULD BE DESPERATELY UPSET AT DESTROYING YOUR DISPLAY, DONT ATTEMPT THIS - SEND IT TO SOMEONE PROFESSIONAL (Pinball Heaven?) - I HAVE TO ADD THAT I DIDN'T THINK IT WAS ALL THAT EASY TO DO!
As we can see in this picture it is fairly typical (apparently!) to see broken pins where the pin goes between the two layers of glass (top right)...
Basically, what we are aiming for is something similar to this, although this was the first of the two pins that i had to repair on this board and as such, the worst job!!
And from the underside...
SO, we take a "Dremel" (or actually i used an el cheapo lookalike for £19.99!) and cut a groove as neatly as possible just above the location of the broken pin. I used a diamond studded tip, or some such. As can be seen in this picture, this is a bit of a nightmare to try and do as you can't really see any of the metal pin as you go along, just loads of glass dust :O)
The hole that you can see more clearly in this picture was my attempt to finally push through to the metal contact below the glass. Things are a bit clearer here as i've wiped the groove out with a damp cloth, but, still no sign of any metal! Getting a bit worried now...
Ah, the ultimate test! Basically, as soon as i got my soldering iron into the groove i'd cut the metal suddenly became visible. Not much, it appears i'd gone a bit off central, but enough to get this wire soldered on - which at the end of the day is all i care about. Here the wire is soldered onto the display unit (or should that be "into"!) and cut to size ready to attach to the underside.
Oops, looks like i forgot to take a picture of the wire attached to the underside, but needless to say, that's just the usual soldering job and a walk in the park compared to what has been undertaken so far. Anyway, this photo attempts to show (amongst the flash) that the repair is NOT VISIBLE at all from the front (don't forget there are TWO repairs on this display unit now).
Here we have a very poor picture of the finished working board...
And here we have a superb, much better picture clearly showing that the missing column (far right) and row (bottom) have reappeared saving me a potentially hideous bill for a new display unit - YAY!