GravoGraph LS800 help

First, thanks for the add to the forum. I was given a Gravograph LS800 that supposedly ran a year ago. A friend owned a business and used it until about 5 years ago and sold the business. It did not come with a computer so, I scrounged am old xp machine and loaded drivers. I am using Coral Draw and Canvas 8 for graphics and have a test program that downloaded and the machine ran but did not engrave. I noticed that the pointer dot is way off and I don't know how to adjust since I don't have a service manual. I would like to test the laser also but again without an diagnostics info, I don't know what or where to start or how to fire it manually. I have talked to Gravograph tech services and they have not gotten back to me. Has anyone here do any alignment tests or adjustments on one of these models. Any help is greatly appreciated. l'm in the Cincinnati area.

Thanks,
LG

First, you can't fire an LS800 manually, at least not an older one...

Second, if the red light is on, the laser can't fire; there's a moving shutter just in front of the laser tube, when the shutter is closed, it blocks the laser beam (electronically and physically if the electric cutout fails), and the back of shutter is where the red-light's first mirror resides. When the shutter is open, the red light shuts off and the mirror is not in position.

If the red light is off and still no fire, then it could be either the tube gassed out from sitting around, or got mis-aligned during the move...

Kev, Thanks for the reply. If I understand you correctly, if the red led aiming/spotting laser is on, then the main co2 laser will not fire. My first issue is that the red led does not hit the second mirror and is hitting the inside cabinet end when it is on. I need to find instructions on how to realign the mirrors for it. If I look (not directly) at the first mirror at the input and output, the led beam is hitting low. I use my camera at an angle to view the mirror. How do I know if the co2 is firing or aligned correctly? Does this require a technician to trouble shoot?
LG

A little masking tape on the target mirror and some trial and error adjustment until a test dot is burnt in the center of the target mirror masking tape. Then on to the next mirror and so on.

Well, I didn't get any instructions ;) --

See this graphic, and I've drawn this from memory, as it takes removing the machine back to get at the parts, and the top cover too for good access, but not sure with an 800, I have a 900... I've only adjusted the red light once, it was kind of hit and miss... IIRC there's an adjustment screw for the first mirror, but any mirror adjustment changes both beams. The trick is to maneuver the red emitter to where you need it.
this is 'overhead' view, looking straight down from the machine's front.
Attachment 397329

Now, before doing any red light stuff, you need to tape the hole over the emitter hole in the back of the cabinet. Send a job to the laser, just a 2" x 1" black rectangle is fine, put it at the lowest 1/2" of table, then have it run at 30% power and 20 speed. Not critical details here, just need the laser to fire to burn the tape and to be able to see it :)

run the job, and if/when the tape starts to burn, hit PAUSE. If it burns, you know it's working and, if the burn is near the center of the tape, then preliminary laser adjustment is okay.

Next tape the gantry (2nd) mirror hole where the beam enters. set the job to run within the last 1/2" of table farthest down, then check the burn position. Then move the job to the top 1/2" of the table and run it. The goal is to have each burn near the center, and if not exactly in the same place as each other, at least not too far apart. (my machine is off about 1/8" from top to bottom of it's 24" span. Your table is 12" I believe, so within 1/8" of each other should be good.)

lastly, check the burn at the lens (3rd) mirror, once at full-left, then at full-right...

Have fun, and report back... :)

Kev, I understand about the masking tape, I just don't know where/which screws to adjust the mirrors and if adjusting the mirrors affect both lasers, the Gravo Tech said that the led and the co2 lasers were not coincident and they were adjusted separately. He asked for pictures of the back of the machine which I sent him of the back and both sides of the machine with it powered on to see the green and red leds on the back of the laser were lit and pics of the aiming led laser on and hitting the inside of the cabinet and reflecting low on the mirrors, never heard back from him yet. Without a manual or expert guidance, I don't want to start cranking on screws and through everything off that may not need alignment. Thank you for your input.
Larry

Without a manual or expert guidance, I don't want to start cranking on screws and through everything off that may not need alignment.

Your best bet would be to call Gravotech and schedule a Tune up Preventive Maintenance for $550. That's the best deal you can get from their on site support, then the tech (me most likely) will service your machine and align it as part of the deal. Other than that, they charge by the hour and travel time, which mounts up quickly.


Nick Michalares

Thanks Nick, looks like I’ll try to sell it as is.