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Joe Pelonio
10-16-2008, 11:00 AM
:mad:
Epilog has not returned my E-mail from yesterday yet, and now their phone is busy (a long time) so I thought I'd try here for advice.

I need help with on my Legend 24tt 45 watt. I was engraving a whole 12x24 sheetof gold Rowmark material yesterday and discovered that all of the text in the center third was fuzzy. The left and right were fine.

First I checked to make sure the table was still level,
and it was fine over the entire area.

I cleaned the encoder strip, and while I was at it, cleaned
the lenses and mirrors, and lubricated the x rail. Same
results.

Then I reversed the plugs on the encoder strip ribbon
cable, and that didn't help either.

Finally, I did a test where I ran each name plate one
at a time, in various places on the table. Every one
comes out perfectly.

As you can see in the picture attached, the words
Mongolian Beef that ran with the head going all the
way left to right, on the left, is fuzzy. To the right of
it shows running it again, by itself, and it's perfect.

I managed to keep running by doing a small area at a time,
until now.

During an engraving run the head hit the right side and kept trying
to go farther, bouncing off the right end over and over until I shut it
off.

I turned it off, then back on, and when it boots up the head goes to
home then immediately to the right again, fast and with a bang.

Scott Challoner
10-16-2008, 11:47 AM
It seems funny that the top of the "M" and the "l" in Mongolian look OK but there is a strip that looks fuzzy. Did you clean the Y encoder strip too?
I don't have an Epilog so I'm going back about 18 years when I worked on stuff with linear encoders, but there should also be a sender and reciever for the strip. Make sure they are clean too if you can get to them. You would think if that was the problem, it would affect the entire length of the strip but it's worth checking. Slamming to right sounds like it's not getting a home pulse. Try manually pushing the head all the way to the home position before turning it on if you haven't.
The stuff I used to work on had two channels 90 degrees out of phase so the machine could tell which direction it was traveling. If one channel went out, there was no feedback and the thing would take off. Perhaps a wire to one of the recivers that's breaking and still makes contact on the outer edges? I've seen it happen.
Just throwing stuff out there. Hope this helps.

Frank Corker
10-16-2008, 11:50 AM
Joe, sorry about your machine, I had that happen once to me and it was a dirty encoder strip. I know you have cleaned it, but give that another go.

Joe Pelonio
10-16-2008, 11:59 AM
Frank, I did clean it again and still no go.

Epilog called, they say the ribbon cable and the little board on top of the head need replacing and are being overnighted ($140). Hopefully that does it, if not there's a chance it's the X-motor.

Meanwhile I have an all day installation today and have to leave now, so I wouldn't be using it today anyway.

Mike Null
10-16-2008, 12:03 PM
Joe

I know you've checked this but I had had the same thing with my Trotec and it always comes down to focus with me. I haven't had the problem for some time but most of what I engrave is 1/32" plastic and it is hard to get perfectly flat hence the out of focus issue.

Frank Corker
10-16-2008, 12:32 PM
Well good luck with it Joe. I'll keep my fingers crossed for you.

Ray Mighells
10-16-2008, 12:35 PM
My 35W did similar once. Went erratic and slammed into the left end. Cleaned the encoder strip, blew compressed air under little board and changed the ribbon cable. I had a problem with the ribbon cable snagging on one of the screw studs inside until I put some tape over it.

Dan Hintz
10-16-2008, 12:36 PM
This doesn't look like a focus issue... X-axis is fuzzy, Y-axis looks clean. Without playing around with the machine, my first guesses are a dirty encoder strip (though it would have to be dirty for a long distance for this issue, so check the encoder sensor itself), or bad X-axis motor / motor drive.

Bruce Volden
10-16-2008, 12:38 PM
Joe,

When you had access to the encoder strip did you clean/blown out the contrast reader that the strip sits in?? I had to use compressed air once and was able to dis-lodge a "mini bunny".

Bruce

Rob Bosworth
10-16-2008, 1:01 PM
You probably have either a dirty, or damaged X axis encoder strip. These strips are fairly touchy. If they are dirty, your engraving comes out similar to what you are seeing. Or, if some of the lines have been removed on the encoder strip, you will have the head act weirdly. Slamming to one side or the other usually indicates a loss of position according to the encoders.

Good luck.

Scott Challoner
10-16-2008, 1:06 PM
I don't know if it's possible, but can the x and y ribbon cables be swapped? If the problem follows to the Y then you know it's the cable.
My money is on the cable. They flex a lot and can make intermitant contact.

Tom Delaney
10-16-2008, 2:17 PM
Joe - same issue with the bumping the sides except mine was to the left. Called Dan and he sent me a new ribbon cable (the one that fits under the bar) and had me clean the encoding strip.

The ribbon cable was that I replaced was almost 'charred' in a few places - definitely smokey but that fixed it.

I kept the old cable since I never did figure out if it was the cable or the encoder but what the hey! Epilog Dan is top notch as far as I'm concerned.

Joe Pelonio
10-16-2008, 4:47 PM
I just got back and based on comments by Tom I dug out the old ribbon cable that I replaced a year or so ago. I installed it (reversed from the original position when it went bad) and sure enough, that works. So, I called Epilog to change my order to just the $25 cable. Brian there was very helpful and waited while I did a few more tests and actually ran something to make sure.

Frank Corker
10-16-2008, 5:24 PM
Hoorah!!!!!

Larry Bratton
10-16-2008, 7:03 PM
Joe never ceases to amaze me with his brillance!
Glad you got it fixed!

Scott Erwin
10-16-2008, 7:07 PM
Glad it wasnt something worse and you were able to get it running with minimal down time.... And less Doe-Re-Me too.... :)

Less than 8 hours from failure to repair...not including the mornign nap, the meeting he was attending while we were posting junk for him to do, lunch, the afternoon nap, and then reading this stuff....

Joe Pelonio
10-16-2008, 10:33 PM
Glad it wasnt something worse and you were able to get it running with minimal down time.... And less Doe-Re-Me too.... :)

Less than 8 hours from failure to repair...not including the mornign nap, the meeting he was attending while we were posting junk for him to do, lunch, the afternoon nap, and then reading this stuff....
:DActually I was on an installation that turned out to be a wild goose chase.

The owner of a new 7 story apartment building in Seattle (was to be condos but most of the pre-sale buyers backed out) wanted all of the ADA signs installed right away for the occupancy permit. We got there and the walls were not painted, and some of the floors were not in yet! :eek:

Back in about two weeks. I don't know what the contractor has been telling the owner . . .

Back to my nap now.