Over the weekend the spoilboard on the Swift was replaced. While cutting the dogholes, it was joticed that the holes were actually ovals. Later in the day a member pointed at very sub par results while flattening a slab, even while well under the recommended feedrate.
Last night I investigated the issue and found the problem. The druve gear on the left side y axis motor had lost its set screws and the motor shaft key had come out. This essentially allowed the motor to slip under load. I’m actually quite surprised we didn’t hear of more racking issues with the gantry.
With the help of @morrism14 and @ewei we were able to identify the thread pitch needed tobreplace the screws. Luckily the key was found under the machine. The right side motor was missing screws as well, so those were replaced at the same time. Red loctite should keep this from happening again.
The machine was reassembled and I cut one test doghole. Back to round. I suspect this issue also caused the bad results while flattening as that would cause a lot of drag on the slipping motor.
The existing dogholes aren’t of much use currently. I may cut a set of temporary holes, or just wait until the board is replaced again.
Many thanks to everyone who helped, and of @Joaquim who was around to lend an ear and photograph the repairs.
