Misalignment

[Nthkentman]

The design was centred, and looked perfect in V Carve Pro screen. Everything where it should be, and the demonstration of the cuts looking good.

The numbers turned out off centre and the words double carved with an offset !
What went wrong?

[Adrian]

Looks like you lost steps. Make sure you didn't hit the limits of an axis at the stage where it started to go wrong. Could be that you were cutting too hard/fast as that will cause lost steps. Also check over the machine with a fine tooth comb to make sure everything is tight and nothing is slipping.

[Nthkentman]

Hmmm... Odd that it cuts ordinary shape outlines without problem Was centre of table and this misaglignment was across the X axis, which there's virtually no play in the ballscrews.


I'll recheck the machine when I am next there

[Adrian]

If the preview is fine in VCarve then it will be a problem with the machine or controller software. I've never known the preview to be anything less than 100% accurate.

I'm presuming there was no chance the material moved while cutting?

It's surprising how different cuts can show up different problems. I had an issue with a tiny bit of free play in my Y axis a few months ago and it didn't show in 99% of the cuts I did but every time I did a tight radius curve the result was awful. Took a fair bit of tracking down as the movement was only apparent under high load.

[Nthkentman]

If the preview is fine in VCarve then it will be a problem with the machine or controller software. I've never known the preview to be anything less than 100% accurate.

I'm presuming there was no chance the material moved while cutting?

It's surprising how different cuts can show up different problems. I had an issue with a tiny bit of free play in my Y axis a few months ago and it didn't show in 99% of the cuts I did but every time I did a tight radius curve the result was awful. Took a fair bit of tracking down as the movement was only apparent under high load.

Hmmmm... This wasn't high load. But I have taken out the play that was in the ballscrew for the Y axis anyway prior to this issue.
I don't *think* the material moved. There wasn't sufficient pressure in the cutting to make it move. Quite well clamped.

Going to investigate the axis's today and see what I can determine

[Nthkentman]

AHAAAAAAAAAAAAAAA!

The mystery is resolved!

I *really* must start to look at the basics before I ask silly questions.

I sorted the Y axis play the other day and all went well. What I didn't do was check the X axis.
Popped the cover off the ballscrew on the X axis and I could rotate the spindle by about 1/3rd a turn ! The driven dog was nice and snug against the bearing housing hence I thought no play when pushing and pulling the motor mount. *BUT* the 1/3rd turn was the clamp around the spindle being loose and allowing that movement radially on the spindle.
Re-adjusted and hey presto...all is accurate again.

This is makin me ead urt trying to remember the basics.... I forgot more than I learned I reckon

[martin54]

well at least it is sorted now & all is good, might be worth making yourself up a little maintenance schedule of things to check on a Daily/weekly/monthly/6 monthly basis. So much to learn that it is inevitable you will forget or overlook things.

[Nthkentman]

Agreed Martin. Maintenance is my job, so I ought to know better... List of weeklys methinks