Here is how I trimmed the Axis screws for the added thickness of the thrust washers (bearings). They are really being used as washers to keep the screws from impinging on the bearing seals.
I thought I might have to protect the screws when in the lathe chuck but I discovered clamping firm but lightly did no damage. Also the screw nut never gets that far down to each end of the screw. I generally use aluminum cut from a soda can for protection when needed.
I was surprised to see the “juices” leaking from the far… Continue reading
I think I need to make one point clear from my previous post. The ball bearings are still taking all thrust loads present. The thrust bearings (fancy name for washers) are there to spread the load evenly and transfer it to the center race of the ball bearing. I looked for washers with very accurate center holes and found them in the form of thrust bearings. I even considered making my own washers as precision washers are hard to find in small quantities. Thrust washers are not hard to find in small quantities. The thrust washer also protects the bearing… Continue reading
I modified the two Y screws on HB2 this evening. I removed the axis screws completely from the machine and chucked them (one at a time) into my Proxxon PD400 lathe. I cut back the 0.250″ diameter shafts at each end an additional 0.063″ – 0.065″ to make space for the 1/16″ thick 1/4″ x 5/8″ hard bronze thrust washers. I also made sure the screw shoulder was absolutely flat to the washer and square to the shaft.
I reassembled all four Y axis ball bearings (new) with a hard bronze thrust bearing (Alloy 932, sae 660) between the shaft and the ball bearing. The flat thrust… Continue reading
I received the thrust washers for the HB2 yesterday. Great quality and FLAT washer type bearings. I am so used to seeing and using stamped washers with a crown and rounded edges and imperfect holes, it is a simple pleasure to see a perfect square edge. Why do I feel good about such a simple part? I guess it is just the precision of a well made part and the machinist in me.