Warco Major CNC build log

[Robin Hewitt]

4 days off, a good time to start
First the Y screw. On the Warco the Y screw locates in to a 21mm diameter pocket 6mm deep cut in the bottom of the carriage (First pic).

I had to finish the nut holder after the machine was apart so I left a rod projecting out the other side for chucking it in the lathe. Looking to mininmise backlash I cut an interference fit with a groove around the bottom to catch any crut.

Pic 2 shows the Y nut fitted but not screwed down yet.

Pic 3 shows the carriage fitted with the spindle sticking out. The first of 2 angular contact bearings is fitted.

The idea is to hold the shaft between two angular races with a quarter ton of thrust locking it in place. To get a quarter ton I'm using pairs of belleville washers.

I have to crush the washers by 1mm and it would be nice if the nut ended up flush with the end of the shaft so I measure it, Pic 4, at 2.95mm then remove 1.95mm from the collar in the lathe.

The fitting has to do both push and pull on the ball screw so it's one solid lump of T6 alloy with a plate for the stepper screwed to it.

[Robin Hewitt]

Next the X axis. Warco bolt the X nut on from below which is a pain because the Y screw is very much in the way. So I'm bolting it from above.

My X nut holder has a lip to hold it square, luckily I can use the mill to cut a square edge in the carriage for it to run against. Pic 1

Now some hard work. The ball nut fitting is slightly larger than the cutout in the end of the table. I know I could jiggle it over the top but it would be a pain forever more, so now I'm setting out for a jolly afternoon with files and angle grinder opening it out. Pic 2

More later

Robin