Apple SilenType printer won't move print roll

[bushok]

Hi, I've just brought my Apple SilenType printer back to life yesterday, hooked up on my Apple II Europlus. Amazing it still prints.

There is just one problem: it won't move the print roll. So lines are printed on top of each other. I suspect a defective electric motor on the print roll rod.

Does anybody here know what the problem could be?

 

[CC_333]

I have next to no knowledge about this printer, but perhaps the bearings for the print roll are seized up a bit? If you can move it by hand though, maybe that's not the case....

However! It's possible the bearings inside the motor are seized up?

I hope this helps sorta...

c

 

[bibilit]

This is a cute printer.

 

[Paralel]

A thermal printer. A good idea, if one can't stand the sound of dot matrix, but I bet the print durability sucked.

 

[Franklinstein]

If you can watch it in action, that would tell you most of where the problem is:

If the motor turns but the roll doesn't, it's probably a busted or stripped gear or the like.

If, with manual assistance, the motor and drum turn, it looks like an electric fault. If the drum turns but the motor won't, it's probably stuck; try freeing and/or lubricating the motor shaft. If nothing turns, try freeing and/or lubing things in sequence.

If the motor turns the drum but the paper just won't move, the drum or other rubber bits have hardened and/or degraded to the point where they can't grab the paper. Try cleaning up the rubber bits to see if it helps increase the friction on the paper.

 

[gilles]

it could be many things:

 _a power supply problem (12v too low in your Apple II+, the printer does not have a separate power supply)

_ on the 3rd photo there is a crack on a resistor network (middle right of the image).

many aging printer issues are with rubber drums  that may just disappear in a small amount of black powder.

 

[bushok]

Thanks for all the replies!

@gilles I don’t see cracks anywhere and don’t believe there are any. Could you point this out with an arrow or circle on the photo?

The rubber rings on the print roll axis are ok. When I turn the knob of the print roll, the paper moves upwards/downwards. 

@Franklinstein I have to try this trial and error method you suggest. The axis of the stepper motor itself does move when unplugged. So it is not stuck. 

Surprisingly there are no gears whatsoever. The axis of the stepper motor just fits in the hollow axis of the print roll. No specific bondage between the two which I find strange. 

Question: with which software can I print properly? Now I typed some Basic that was suggested in the printer manual (page 12, found here http://www.apple-iigs.info/doc/fichiers/apple_silentype_operation_and_reference_manual.pdf):

100 PRINTRINT "GAME CONTROL ZERO IS ";PDL(0)
110 PRINTRINT "AND CONTROL ONE IS ";PDL(l);"."
120 END

 

[Franklinstein]

 Surprisingly there are no gears whatsoever. The axis of the stepper motor just fits in the hollow axis of the print roll. No specific bondage between the two which I find strange. 

I see that better now that you mention it. It's probably a pressed/friction fit. Look to see if the receiving part is cracked. If so, it may be possible to use a VERY SMALL amount of glue to secure the axis of the motor to the receiving part on the print roller. If you use glue, make 100% sure it does not enter the motor bearing. An epoxy would be preferred.

After many years of use in friction fit assemblies such as this, the receiving plastic tends to crack and spin uselessly on the metal part that it has been pressed onto. For example, it's a well-known fault in Sony Betamax VCRs (usually at the drive motor for the cassette loading mechanism) and CD players (usually the tiny cog on the optical block sled motor).

 

[gilles]

It may be something else but on this photo I see a crack (that I cannot see on the other photo)

 

[bushok]

@gilles Thank you for pointing the 'crack' out. It is not a crack though  But there WAS a crack in the adapting plastic 'cilinder' (from here on I will call it 'adapter') that connects the print roll rod to the stepper motor (see attached pics). At first I did not see it because it is black and tucked away in a shadowy place. @Franklinstein came with the right hint (see above), I glued the adapter with thick power glue to the print roll rod and after that dried, I glued it to the stepper motor.

This is a risky business, you need to open up the printer and remove the circuit board and stepper motor in order to do this. In my case the orange flat ribbon cable slipped out of its fixed socket on the circuit board. This is very hard to get in properly without bending the 'fingers' of this cable. But I managed to do so. Many thanks to everyone who reached out and a special thanks to @Franklinstein for the golden tip! 

All is working well now. I do offer the printer for sale on eBay, you can find it here: https://www.ebay.nl/itm/323604864832? You can see the printer in action here: 

 

[Paralel]

I wish I had known about these Silent printers when I was a kid. I wasn't allowed to get a printer until InkJet technology was invented because my mother has severe hyperacusis and as a result, misophonia (Imagine the sound of a dot matrix printer, but several octaves higher, and probably 9x as loud, that's what she would hear. It's a disorder of the inner ear, and there is no decent treatment nor cure). This would have been great. Of course being a kid, and there being no internet, I had no idea such technology existed. It's too bad the paper sucks and fades rapidly, is crap to write on, and it turns out has been made with some rather nasty chemicals. Now, if anyone managed to make a technology like this that solved those problems, they'd be assassinated before anyone knew about it because of "BigInk"

 

[gilles]

@paralel: some typewriters (and maybe printers also) used thermal transfer that is similar but with a ribbon and prints on normal paper. Silent and durable (but ribbons are expensive and there is a very annoying confidentiality issue). I think canon used this technology in the end of 198x years.