Well had a few disappointments with the Beaver, first was the X and Y backlash, it was worse than I first thought but I have sourced some new ground ballscrews of similar dimensions (X 1600mm x 32mm dia x 10mm pitch, Y 900mm x 32mm x 10mm pitch) Not got them yet but hopefully they will be here this week and I will get them machined at the weekend.
Next thing I found was that the Y axis had a huge amount of slop, I tried to adjust the gib but it was fully in and there was still loads of slack, I removed it and found it was in the wrong way and had extra peces screwed on either end. It was the extra pieces that was stopping the adjustment as the gib goes right through and there is a screw front and back that holds it in the right position. Ok so I fitted it the correct way and without the extra bits and got it adjusted as per manual but as I wound to either extent the servos tripped after a few seconds so had to slacken off again.
The beaver has the Y ballscrew along the right side of the knee and the procedure for adjusting the gib is put two clocks (DTI) on the knee and plungers against the saddle, one at left and other right side, you then wind three full revs of the clock and zero then wind one back and the difference between the clocks gives you the amount of twist due to slack gib. The manual says adjust until 0.025mm (0.001") and the best I could get so that the drive wouldnt trip was 0.09 and even then it would trip after ten mins sitting at the Y minus extreme.
This weekend I got a loan of a Biax and had a go at scraping the unworn parts and although I have never done scraping before it wasnt too hard. I think the hard part of scraping would be to scrape an axis true to another but as I only had approx 100mm either end to do it wasnt that hard.
So now I have it scraped its seems good, have it adjusted to 0.018mm or so twist at the slackest part and less than half that over the majority of the rest of the travel, motor current when monitoring from the serial connection to my drives shows only a slight increase in current at either extremes and it is approx 8 amps which is around half of the continuous rated current so should be fine.
I also monitored the current whilst doing some milling today and it never went much higher than the 8 amps so I am happy
just hope the ballscrews turn up soon.
Hood