GCC Spirit Laser Problem

[David Sabot]

We have a 40 watt GCC Spirit laser engraver. One of my employees was engraving glass and didn't realize that since the glass so was far inset that they had to make sure the laser head didn't go back to HOME when finished engraving.

Needless to say the head smashed against the item and fell off the track.

I've been working for 3 days to get it back up and running. There doesn't appear to be any visible damage, and was able to get the head back on the track and everything is nice and tight. However when we engrave we are getting wobbly lines, and skipped areas as well:

IMG_0826.JPG
IMG_0827.JPG

The only thing I can think of at this point is a problem with the X motor. Any insights.

[Rich Harman]

I would check the motor or idler shaft for wobble - or something in the drive train that is off center.

[David Sabot]

I'll see if I can "see" anything wrong with the motor. Not sure what the idler shaft is.

[Rich Harman]

Not sure how yours is set up but there will be a pulley that is turned by the motor and another free spinning pulley on the other side of the gantry - that's what I mean by idler.

[Kev Williams]

Your engraving shows erratic X-axis movement in most of the text, but the tail of the "p", the movement is fine...

Ever hit a rock with your lawnmower badly enough that the mower wouldn't start afterwards? What happens is the shock of sudden stop snaps the flywheel-to-crank woodruff key, and the flywheel keeps moving on the crankshaft. With the flywheel out of position, the ignition can't fire the spark plug--

I'm thinking the sudden shock of your 'rock' probably caused the drive cog on the X stepper to stay in position while the drive shaft kept moving, and it's likely loose. Your stepper shaft likely has a flat that the set screw tightens against, and the shock probably smooshed the set screw enough that it's no longer holding the cog tight to the shaft, letting it move slightly as the machine changes direction. Across the tail of the p, the direction change is so fast the cog stays in place...

anyway, what I see can all be explained by a loose set screw!

[Chad Fitzgerald]

Hey David,
I have the same machine, i assume the laser head is on the track with the "skateboard" looking rollers? silver piece of metal with black rollers, 1 top, 1 bottom.
Looking at you pics, is it possible one of those got bent, therefore causing it to not roll smooth? if that makes sense. kinda like an oval wheel would roll.
Chad

[David Sabot]

Hey David,
I have the same machine, i assume the laser head is on the track with the "skateboard" looking rollers? silver piece of metal with black rollers, 1 top, 1 bottom.
Looking at you pics, is it possible one of those got bent, therefore causing it to not roll smooth? if that makes sense. kinda like an oval wheel would roll.
Chad

Yeah it has the skateboard thing like you mentioned. I looked at all the rollers and they appear to be in good order.

[Scott Shepherd]

I agree with Kev, what you're seeing is a shift that could be happening because a set screw is loose on a shaft.