At this time, I am searching for items for my new project, the moving gantry CNC machine. One of the items that I find difficult to find was the spacer for the ball bearings. Essentially it was a washer which was to be placed between the inner race of a bearing against the machine body, leaving a space for the outer race to move freely.

However, it was not the usual kind of washers which you could easily find at the hardware stores. Ideally the diameters of both the inside hole and the perimeter circle should just be the size of the inner race.

Well, I could not find any steel washers that suit my specification, i.e. inner diameter 8 mm and outer diameter 12 mm. The hardware storekeeper told me that they could order copper or aluminium washers for those sizes, which were essentially gaskets for banjo bolts. I might consider using them if all other options failed.

I did find some sort of stainless steel rings in one fishing equipment store, but they were quite expensive, because they were of high quality and were used by fishermen who were serious about their fishing gear. I don’t need such high quality rings.

One online store needed me to order in large quantities, which I don’t intend to do.

I thought, what the heck, since I just needed a few, why don’t I machine some of them using my movable bed CNC machine, just to see whether I could produce them myself.

I happened to have some off-cut pieces of hard phenolic electrical insulation boards lying around and thought that maybe these could be workable. Otherwise, I would have to mill them out of aluminium sheet, which would undoubtedly wear down my milling bits.

So off I go to fabricate them. The space left in the off-cuts were quite limited, so I could only fit 4 pieces for this trial attempt.

The video below showed the process of cutting the spacers.



The spacer washers were cut off successfully from the phenolic insulation board as per my program. My next step is to test whether they have sufficient mechanical strength without breaking when they were compressed by the bolt and nuts.

That would be sometime in the future – until all the component parts of the movable gantry cnc machine had been cut out and ready for assembly.