Help with a scanning head gavo

[whitfieldwelding]

Hey guys,

I'm new to the forum and scanning lasers. I don't actually have one for home I work with them at work. I have an engraving head and I use a fiber laser to engrave molds. I took the head apart to clean it and make some
structural adjustments. Then the next day when I ran it my normal 6inX6in scanning field was cut in half along
the y axis. I took it back apart to see if I had clipped any wires or hit any thing, but I did not.

I have been playing with the idea of tunning it but everything is still in tune. It seems like the gain on the y
axis just somehow cut itself in half. If anyone knows anything about the control boards circuits or what the
possible problem could be let me know.

um also my pci control board is fine it puts out the proper voltages. As well if I change the x and y galvo
motors the problem switches axis.

One final question, should I be able to tune the y axis up to match the x axis or is it too much of a gap?

Any help would be appriciated.

[ShortyInCanada]

So I'm kinda new here but my take on this is :
To the X axis galvo you have an analogue waveform (like a sign wave for example).
To the Y axis galvo you also have an analogue waveform (like a sign wave for example).
Your problem is that one half of one of your waveforms isn't being "drawn" out by the galvo.
If you change the signal over to the other galvo the problem is the same.

So you seem to have a signal problem as switching the units proved that they are working to spec.

Find out why part of one signal isn't making it to the final unit in the stream.(the galvo)
Is a pin to connector bent ?
Has the signal wire been clipped or bent to the point of a failure ?
Check that connectors are not corroded or plugged with a small bit of non-conducting matter.

You will need good light and very clean working conditions.

That's my 2 cents worth.
Hope it helps.

[taggalucci]

Sounds like a signal voltage issue. If you have differential (+, - & ground) you may only have half a signal be cause you're not getting the full difference between + and -, only + and ground or - and ground. E.g. If your signal is +10V and -10V then the full signal is 20V, but if you you only have one side the you're max signal is only +10V or -10V.

[taggalucci]

...so check your wiring and use an oscilloscope to confirm your signal is good before changing anything e.g. tuning. You could otherwise damage the scanners if the problem suddenly rectifies itself and you have the full flood of voltage.

[catalanjo]

...so check your wiring and use an oscilloscope to confirm your signal is good before changing anything e.g. tuning. You could otherwise damage the scanners if the problem suddenly rectifies itself and you have the full flood of voltage.

I agree entirely, if it turns out that it is not a loose wire on the differential signal then it means the inverting op-amp of your output stage needs looking at.

Cheers