View Full Version : Issue with Epilog optics inside tube

Bruce Clumpner
05-08-2014, 2:10 PM
I'm having an issue with alignment/diffusion of my CO2 beam and need an opinion. I'm running a 10 year old mini-18, 35 watt Epilog. I'm 13 months into a new tube, and now that I see this again problem, my 1st tube probably had the same issue. I'm getting my beam split somewhere in the optic pathway before the red dot merges into the path. It's obviously resulting in a loss of power and consistency.

288937 The anodized tag shows the loss of consistency. Left side is 1-pass at normal setting of 50s & 50s. Right side is 3 passes at 50 speed & 100 power
288936 The blue tape shows the burn and how the beam is being diffused at the scanning head
288938 Here is the beam before it hits the 1st mirror on the x-axis (the far right burn was a previous test)

Since Epilog tech support says the only way to fix it is to open the tube, I've got to replace it. I'd like to diagnose the issue a little better so that I'm not going through this again in a year.

Any thoughts?

Also anyone have experience dropping a higher power tube into an epilog? I'm thinking about moving to a 45Watt unit.

Thanks as always...

Joe Pelonio
05-08-2014, 7:45 PM
I can't help you with any trick to solve the split beam, but on the power upgrade do you have the manual? My laser was available at 25-45 watts, I have 45 and Epilog confirmed what it said in the manual, it is at the maximum for the model.

Allen Rawley
05-08-2014, 11:47 PM
We upgraded our customer from a 35 watt to a 70 watt and the customer followed the instructions and said it was easy. To upgrade from a 35 to a 45 watt is simpler, as both lasers are the same size and the power supply remains unchanged. You can find the instructions on the Epilog support website.

Regarding the split beam, a more thorough analysis can be done by doing a mode burn (laser burn on tape is adequate). The location to do this is after the laser and before the first mirror and the red dot pointer. The reason is that you may find that the optic for the red dot pointer is bad and/or the first mirror at the laser is bad, and these certainly costs much less than a laser tube.

A suggested approach is:
1. Get the instructions for replacing your laser tube from the Epilog website, as it has good photos and instructions. Also download the beam alignment instructions for the mini and helix.
2. Remove the laser but not the wiring and set it on a table right at the back of the laser machine
3. Test the laser spot for splitting (confirm that the issue still exists)
4. If the issue still exists, then remove the red dot pointer from the laser. Do not disassemble the laser resonator. Just remove the small box in front of the laser to remove the red dot pointer.
5. Then, perform another laser burn. If the problem does not show up, then get replacement optics from Epilog

A word of caution. This type of troubleshooting will require a beam alignment with the red dot pointer, so if you are uncomfortable with performing a beam alignment then have someone technically oriented perform this service.

The Epilog support site has an excellent guide for beam alignment, including a detailed description of the red dot pointer assembly and how to adjust the first mirror.

Zlatko Kursar
05-09-2014, 2:24 AM
I have the same problem on my Epilog. It is my second tube.

Bruce Clumpner
05-09-2014, 5:47 PM

Thanks for the idea to test the optics in the red dot box...Since I need to pull the laser anyway, I might as well test it out of the machine... Already pulled it to do a visual inspection and thought everything looked pretty clean. Realigned everything and still works for raster work, just not enough power getting through for vector cutting... Took 4 passes @ 5 speed/100 power to get through 3/16" plex...

Dan Hintz
05-10-2014, 9:23 AM
If that's the beam as it leaves the tube, you need to get the tube repaired, plain and simple. Scary part is, that looks like TEM01 mode, not TEM00... some funky stuff going on there.

Bruce Clumpner
05-12-2014, 12:28 PM
After fighting a last minute rowmark job last night, I've decided to upgrade the tube. Going to move from at 35 watt synrad (stock?) to an Epilog 40 watt tube for a couple of reasons.. First they double the warranty to 2-years, then, even though it's rated at 40 watts, our local distributor says they usually meter out 10% above their rating. 45 Watts, woo-hoo! Then finally, the cost to re-charge their tube is 30-40% less than what they charge for the stock tube.

Now just to get it there and back by the end of the week so I can run my outstanding orders...

Thanks for everyone's input.

Bruce Clumpner
05-13-2014, 2:48 PM

What's the difference between those modes and how do I evaluate which mode it's operating in on the Epilog? All tempered for an clueless electronic dinosaur?


Dan Hintz
05-14-2014, 7:39 AM
Don't worry about the mode, Bruce (it should be TEM00 for these tubes), just get that puppy repaired. It was more of a side-comment on the shape of the burn mark...

Craig Matheny
05-15-2014, 4:00 PM
I just had the same issue not as bad of a separation about 1/2" it turned out to be the mirror on the side of the machine ever so slight scratch split the beam replaced the mirror and it was perfect also before you pull the tube check the red dot on the side arm of the machine see below. I would send pics but in the process of moving to a new location so they are packed up.

Pull the left panel, look at the arm that moves front to back there is a small hole that the beam shoots through put tape there or your bulls eye in the circle and check your red dot (do not fire the laser) see if it is split. If it is split the issue is towards the laser tube if not towards the lens (check all the mirrors in either case). I also use this location to align the laser on a new tube installs it gets everything very close learned this on a Trotec demo not sure why Epilog does not share this info?

Bruce Clumpner
05-15-2014, 4:37 PM

Too late, the tube is now in Colorado, but I did check the beam alignment before that mirror on the x-axis. One of my photos (3a) shows the split at that position. I'm taking this down time to clean all the optics in the path just to insure I get all the power from my new upgrade.