retrohax.net

… or did I just spend lots of time figuring it out?

INTRO

ImageWriter II – two

Some time ago, I wrote a blog post about the Apple Image Writer II ribbon cartridges. Back then, I had a very nice ImageWriter II printer to sort out, so there were no issues with it, and it only required cleaning. However, I had another Imagewriter II that was not working as expected. In this short blog post, I will show you the hard-to-spot fault and how I fixed it.

I’ll skip all the cleaning details as these are obvious. Let’s jump right to the raw meat.

Printing a test sheet shows a few issues. Clearly, the print head is too far away from the paper.

At first, I thought it could be quickly corrected with a few adjustments.

Setting the tension didn’t help at all, as the other side of the rod was still kinda loose.

I’ve looked up some manuals for this printer, and it turned out that I can use shims to fix this issue.

Apple Technical Procedures ImageWriter II

SAMS Computer Facts – ImageWriter II

The original shim is shown in the picture below.

I’ve decided I’ll make a new shim myself out of a brass sheet.

After replacing the original shim with the new one, the printout was a bit better, but still, letters were missing the top half.

The next idea was to thoroughly clean the print head. I’ve removed it, inspected and cleaned it under the micro cam.

That didn’t help much…

I figured that maybe some pins are stuck, so I’ve desoldered the print head and took a look inside.

Turned out that, although a bit dirty, all the pins are moving nicely, so again … no, that wasn’t it 🙁

The actual fault

It took me a decent while to spot that one. After removing the X-axis assembly, I finally spotted a broken roller that was causing all the printing issues.

A few moments later, I had a model ready for 3D printing, so I printed 4 pcs just in case 🙂

Model links at the bottom of the blog post

Final assembly and tests.

The only thing left to do was to remove the brass shim as it was pushing too hard now 😀

Model for 3D printing

Outro

See you in the next post as I am slowly going back to writing 🙂

Tons of material to cover.