The ongoing saga - this time on wood - engraver not finishing the job

[Paul Williams from Nunavut]

Thank you for some of the things to check with my earlier problems, after replacing my lens and mirrors. The problems persist, though.

On another medium, this time cedar planking (of the sort you might bake a fish on), that I've coated with Varithane, I now have an issue (maybe related to the earlier woes) which has the engraving starting off strong and fairly deep, but then beginning to fade away about 5 inches along the x axis to eventually nothing. The engraving was taking place in this instance at 60s and 100p.

As seems to be normal for me, Sawmill won't allow me to upload a photo, but here is a link to an image of the offending piece on my dropbox:

https://www.dropbox.com/s/xl5h52i86dnv3gd/2015-12-14%2016.16.38.jpg?dl=0

I was able to do the job by turning everything onto its side and engraving in the first 5.375 inches, but that further limits the size of stuff I can do, and quite honestly is a hassle. Any suggestions would be greatly appreciated. Thanks.

[Ross Moshinsky]

That's indicative of a focus issue or an alignment issue.

[Mayo Pardo]

The only things I can think of checking are,
1. Is the wood uniform thickness?
2. Is the bed of the machine at a uniform distance across the entire X axis in relation to the beam?
3. Is there any possibility that something is blocking the laser path at the point where your power seems to drop off? Does the Epilog have a built in red dot pointer that indicates where the laser will fire on your material? If so, does it disappear when positioning the laser in that dead zone?

[Jack Clague]

First thing i would check is the focus from the left side of the table to the right, move the laser head to the far left, check the distance between lens and table, then move the head to the far right and check again, they should be identical distance or atleast within a 1/10 mm. do the same for top left and bottom right

[Bert Kemp]

Yes it looks to go out of focus as it travels from left to right Check the bed make sure its level check the gantry make sure its level. then check your mirror alignment.

[Paul Williams from Nunavut]

Based on the above questions, it seems to be an alignment issue. The board is uniform, the table height is uniform, nothing is causing the gantry to jitter, and the red dot stays in place.

I assume that there is a forum thread on how to check the alignment?

Thanks folks, I'll get on it later today.

[Ross Moshinsky]

Call up Epilog. They will send a PDF on how to align your laser. It should be a relatively painless process that should only take you about 20 minutes to complete.

[Paul Williams from Nunavut]

Many thanks. Will do.

[Paul Williams from Nunavut]

Thanks for all the help, folks. It was an alignment issue, and the fix was simplicity itself, once I got over the fear that I was going to mess it up even worse. The plastic name tags are now streaming off the assembly line, and the wooden plaques are looking much much better. I am grateful. Cheers, and merry Christmas or Happy Hanukkah, or Happy Holidays to one and all (I hope I got all the correct phrases in).