Hi all,
I am going out on a limb and hoping someone here may have some insight to offer on this problem. I will preface by saying that I am a machinist and know very little about the mechanics of CMMs.
My friend has a Brown & Sharpe MicroVal PFX 454 CMM. This is originally a manual machine, but has been retrofitted with CMM Manager software and a semi-automatic probe head (the type that is capable of automatic motion by manipulating the head position using a ball on the table). It was bought a year ago and has never been properly working. A few months ago, we had Hexagon come take a look at the machine. While here, they also replaced an encoder and the Y-axis glass scale. The main issue with the machine seems to be that it is "hunting" on the Y-axis, as well as not tracking. The Hexagon tech hooked up his diagnostic tools to the CMM, and while attempting to order the machine to move, we found that the Y-axis location readout was never changing on his software, even when the axis was moved by hand. When he tried to order the machine to move automatically via his software, the machine would find a position, but then begin "hunting" on the destination. My understanding of "hunting" is that it was not able to find the precise point to which it was told to go, so the axis begins driving back and forth over the point rapidly. This caused vibration throughout the machine.
The Hexagon tech believes that the problem lies within the controller (I have to say that even given my limited experience with CMMs, the Hexagon tech did not seem knowledgeable or competent at all in his understanding of the technology). He referred to these types of controllers as "throwaway" controllers because everything is on one board. In order for them to even attempt to repair the board, the entire controller must be sent to B&S and they attempt repairs at the board level.
Has anyone encountered issues like this before with the same or a similar machine? My friend is a good guy and while he probably could have done more research before he bought the machine, I hate to see him stuck with a CMM paperweight.
Thanks!
I am going out on a limb and hoping someone here may have some insight to offer on this problem. I will preface by saying that I am a machinist and know very little about the mechanics of CMMs.
My friend has a Brown & Sharpe MicroVal PFX 454 CMM. This is originally a manual machine, but has been retrofitted with CMM Manager software and a semi-automatic probe head (the type that is capable of automatic motion by manipulating the head position using a ball on the table). It was bought a year ago and has never been properly working. A few months ago, we had Hexagon come take a look at the machine. While here, they also replaced an encoder and the Y-axis glass scale. The main issue with the machine seems to be that it is "hunting" on the Y-axis, as well as not tracking. The Hexagon tech hooked up his diagnostic tools to the CMM, and while attempting to order the machine to move, we found that the Y-axis location readout was never changing on his software, even when the axis was moved by hand. When he tried to order the machine to move automatically via his software, the machine would find a position, but then begin "hunting" on the destination. My understanding of "hunting" is that it was not able to find the precise point to which it was told to go, so the axis begins driving back and forth over the point rapidly. This caused vibration throughout the machine.
The Hexagon tech believes that the problem lies within the controller (I have to say that even given my limited experience with CMMs, the Hexagon tech did not seem knowledgeable or competent at all in his understanding of the technology). He referred to these types of controllers as "throwaway" controllers because everything is on one board. In order for them to even attempt to repair the board, the entire controller must be sent to B&S and they attempt repairs at the board level.
Has anyone encountered issues like this before with the same or a similar machine? My friend is a good guy and while he probably could have done more research before he bought the machine, I hate to see him stuck with a CMM paperweight.
Thanks!
