The time came to renovate the new focusser. Whilst it was quite good upon arrival, the draw-tube with negligible slop, it was still not up to my standards. I removed the draw-tube, and discovered these within its run, and as bearings or shims...
They straddled plastic ridges which act as permanent, molded bearings for the draw-tube, to centre same.
At first, I thought that they might be of woven metal...
But they appear more like woven fibre-glass, after I examined them more closely. You can see within that image how the "fabric" has been damaged, and where it had straddled a ridge.
In any event, I had never seen anything like that being used as such. I've always been used to seeing these...
...corrugated plastic strips, which bear an eerie resemblance to the paper-trays of cherry-rolls or coffee-cakes. I have always removed and replaced those.
Life's too short, so out they came. This time round, I left the plastic ridges within the run alone. I had ground them down within the original focusser, and to make way for the strips of PTFE.
These are the screws for attaching the original focusser to the optical-tube...
You can see how I've X-ed them out. They're like sheet-metal screws, but for plastic. They work okay, and there are three pre-drilled pilot-holes for them from the factory, round the new focusser's flange, but I wanted better to secure the focusser. Common and stainless steel hardware...
I had to drill new holes into the new focusser's flange to match the position of the holes of the optical-tube. Three #6 common-steel nuts were sanded all over, and the new holes abraded then scored from the inside...
The nuts were then epoxied into place, the epoxy sloping up and surrounding the sides of the nuts, and secured until the epoxy hardened...
You can see the factory's pre-drilled holes within that image.