Hi Guys,
some updates from my side in regard to the Image Writer I refurbishment.
The unit came in the original box and in excellent aesthetic conditions.
However, it would just turn on and off and do nothing more.
First issue: a lot of rust. Yes, plain rust on the lower head rail. I had to disassemble, thoroughly clean and lubricate the whole assembly before the printing head could freely glide edge to edge.
As I was disassembling the body panels, I could notice that the pathetic strips of acoustic foam were crumbling away. Replaced.
All the rest was in good order, except, of course, for the ribbon.
I got two units, one still sealed and one simply stored away in a plastic bag.
In both of them, the foam rollers were disintegrated and kind of rotting away (mildew?). So I wanted to replace the foam with something similar.
At first I tried with felt, but the grip is not sufficient for winning the resistance of the ribbon (it also gets twisted, which generates additional friction). Eventually, I ended up using some foam feets 20 mm in diameter and 5 mm thick. I trimmed a hole of 8 mm and the fit is indeed very OK for the pulling head. As for the counter head, which is spring mounted, the spring is allowing a fair amount of play, but the mounting pulley is indeed asking for some 18 mm max and 4 mm, which I could not find. So I used some rubber bushings I had around and the result is OK.
As for the ink, for the sealed unit the inking was still there and I could print without any problem. Nice. Still, I wanted to try and revive the ink on the dry unit. A quick search suggested nothing less that WD40, aka "the universal magic stuff" (I'm sure that somewhere there's someone suggesting to use Coke...).
And yes, WD40 worked its magic and the ribbon could print again.
Hower, big "however"... Dosing is extremely critical. The ribbon has to remain as "dry" as possible, the ink should be a kind of greasy, waxy like compound to be transferred on the paper, not to soak it. So, I had to scrub the ribbon twice for removing the excess of WD40. Still the printed characters tend to smear off when compared to the original ink.
So, next time (assuming there will be a "next time") I will definitely try to revive the ink by using, well... plain ink. I guess one possibility could be to replace just the ribbon, it shouldn't be too complicated.
Anyhow, for casual printing even WD40 is fine, especially considering the printer is almost 40 years old...