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Keith Downing
05-19-2017, 3:58 PM
So, I have recently acquired an Epilog Summit laser. Try not to laugh.

I had used it a few times and it vectored perfectly, but weakly. But didn't fire at all when rastering. The previous owner had experienced the same thing, and we both assumed the tube needed a charge. I knew this going in, obviously.


I had the tube recharged by the guys at Evergreen last week. It came back strong, but now I'm getting some strange results on the machine.


Here is the abridged version of what is going on:





The machine will fire in alignment mode, but it takes some coaxing. Holding the left door trigger, it takes hitting the right door trigger 2-5 times to get it to fire. Sometimes I even have to wiggle it for 4-5 seconds before anything happens. This doesn't seem right.





I did get the machine (I believe) reasonably well aligned, but it took about 2 hours. I don't think it is affecting anything (because the beam is aligned to strike the lens in the lower portion) but the main mirror over the lens is starting to flake at the top.





The machine will raster basic shapes and words BUT it starts late (consistently missing the top 10 to 15% of the design). And it seems to cut out intermittently at speeds over about 70 to 80%.





Vectoring also starts late for the most part. I got a few shapes to cut all the way around, but for most the laser started firing after about 5-10% of the design had passed. Also, I don't know if it's related to my problems, but some of the corners of the boxes seem rough and the circles had some uneven points. Could just be that I'm used to a machine that cuts better though.




I'm kind of at a loss as to where to start troubleshooting since this machine is relatively new to me, and also old enough Epilog doesn't support it any more.

I've reached out to Evergreen to see what they think, but in the meantime I thought I'd appeal to the community here for help. I know at least a couple people are still running these machines. Right?

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Lyle Cheredaryk
05-19-2017, 6:00 PM
Keith,
By "door trigger" I am guessing you mean the safety switches on the doors? Sounds like they need adjustment or replacement. Personally, for testing purposes only of course, I would bypass them to see if they are the cause of any of your issues.
A good starting point anyway.

Lyle

Keith Downing
05-19-2017, 6:28 PM
Keith,
By "door trigger" I am guessing you mean the safety switches on the doors? Sounds like they need adjustment or replacement. Personally, for testing purposes only of course, I would bypass them to see if they are the cause of any of your issues.
A good starting point anyway.

Lyle

Yes, on this laser the door switchers are the triggers for the laser to test fire in alignment mode.

I've thought of bypassing them as well and it is on my list of things to try if nothing else pops up through a little more testing. But in this case they do serve a purpose during the testing/alignment.

Bill George
05-19-2017, 7:17 PM
Yes, on this laser the door switchers are the triggers for the laser to test fire in alignment mode.

I've thought of bypassing them as well and it is on my list of things to try if nothing else pops up through a little more testing. But in this case they do serve a purpose during the testing/alignment.

I thought RF lasers needed a "tickle" adjustment to make sure they fired on time.

Keith Downing
05-19-2017, 7:21 PM
I thought RF lasers needed a "tickle" adjustment to make sure they fired on time.

I talked to a couple guys about this, and I'm waiting to hear back from another. But my understanding was that this machine wasn't like this before and it shouldn't be this serious of an issue after the laser has warmed up regardless.

I'm curious to hear more if anyone has something to add on this subject. But my problem persists even after I've been using the machine for awhile and give it a break of just a few minutes.

Bill George
05-19-2017, 7:26 PM
I thought tickle was more like a bias adjustment, as we used to do on the old vacuum tube stuff... set so it just almost triggers the tube. There are experts on here that can add a lot more.

Keith Downing
05-19-2017, 8:26 PM
I thought tickle was more like a bias adjustment, as we used to do on the old vacuum tube stuff... set so it just almost triggers the tube. There are experts on here that can add a lot more.

I'd definitely like to hear more then!

Kev Williams
05-20-2017, 3:11 AM
Per my Gravograph manual:


"Tickle" is the term used for small pulses, which are fed to the laser to keep the plasma inside energized. This allows the laser to respond quickly and strongly for high-speed cutting and engraving.

Tickle keeps the laser <warmed up> at times when the laser system is powered on but not firing and the top door is closed. We suggest keeping the door closed at all times....to keep the laser warmed up. [no power to the tube if the interlock is open]

I set my tickle up a few notches once, and I could see the laser fire occasionally, like 1 'pop' every few seconds. Since I keep my door open and I value my fingers, I keep the tickle at the factory default setting, which I believe fires less often and at much lower power because I never see it, and haven't felt it -- yet ;)...

Bottom line is, tickle has nothing to do with the laser when in use, only when NOT in use. So Keith's problem isn't tickle. I'm more inclined to think it's a loose wire issue with the interlock setup...

Keith Downing
05-20-2017, 9:46 PM
Per my Gravograph manual:



I set my tickle up a few notches once, and I could see the laser fire occasionally, like 1 'pop' every few seconds. Since I keep my door open and I value my fingers, I keep the tickle at the factory default setting, which I believe fires less often and at much lower power because I never see it, and haven't felt it -- yet ;)...

Bottom line is, tickle has nothing to do with the laser when in use, only when NOT in use. So Keith's problem isn't tickle. I'm more inclined to think it's a loose wire issue with the interlock setup...

Yeah, and I don't think this model has that feature anyways. I can't find any mention of it for any of the machines before about 7 or 10 years ago; and of course no mention of it in the Summit manual either.

Other ideas?