After a long time I finally finished the printer.
Prologue: This printer was at the end of the 1980’s the first printer of my father. All the time the printer was more or less handled with care and found 2021 it’s way back to me. I got this printer from my dad in the 1990’s together with the ATARI 1040 STFM and I gave it to my mother’s life partner Theo that time after I got an EPSON color inkjet on a birthday or for Christmas.
Theo used the printer sometimes and badly modified it a bit. The moving mechanism of the ink ribbon stopped working due to the old rubber belt. But instead he swapped the belt with a new one he drilled a hole in the lid and moved the ink ribbon by hand. But there are also no spare parts for this printer anymore so he also couldn’t use a new one.
But with a lot of time and math I found a new spare belt.
What have I done?
I disassembled the whole printer so it was only the base with the roll left.
I cleaned the base, cogs on the side and all other dusty and dirty parts. But before I’ve done this I cleaned firstly the case of all the old dust and grime. I found some old food moth odds. After that I cleaned the mainboard and re-assembled all part by part. I also gave the cogs and print head rods new grease.
At the end I gave the printer a new belt for the ink ribbon mover. That was kinda tricky because I didn’t found any information about the belt size in the Internet or the service manual. I also writ the NEC support and they asked NEC Japan if they had any informations. But didn’t got any reply of NEC after a long while so I started to looking for help by specialists how to calculate the right belt size.
Here the formula: ((Ø 1. Wheel x 0,5) x Pi) + ((Ø 2. Wheel x 0,5) x Pi) + (axial distance x 2)
Calculation: ((27,16 mm x 0,5) x 3,14) + ((20,27 mm x 0,5) x 3,14) + (46,34 mm x 2) = 169,19 mm
So I need a belt with a pretension of 5% so that’s why I had take the size of 160 mm. I ordered a special PU belt with a diameter of 2mm on eBay that was specially made for me. Now the printer work like a charm again!
And here the printer re-assembled at its glory:
On the end a small video. Sorry for the potato camera but I had only my old Olympus VG-160 digicam in the basement.