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Glen Peters
08-09-2004, 7:23 PM
My machine is a Pinnacle M-Series 25 watt

The other day I noticed that the laser was cutting about an eight of an inch lower than where I had placed the object in Corel. I went thru the steps to reset the home position. To test it I sent a 1 inch square to be vector cut in a piece of printer paper to the laser, carefully placed the paper on the vector cutting table and pressed auto focus. The table started moving up, the probe contacted the paper, table continued moving up, probe punched hole in paper, table still coming up, lens carrier hits paper, table still moving up and finally everything ground to a halt. After a bit I got everything separated so I could assess the damage. Nothing appeared to be loose, the lens carrier and rail moved freely and the only physical damage was a large crater in the vector cutting table.

Figured the auto focus probe was dirty so I cleaned and polished so it was shining like gold and moved very freely. Made a mental note to clean often and thoroughly. To test it I ran the table down as far as it would go, kept one finger on the power switch, pressed auto focus and then pushed the auto focus probe in. Worked as advertised. Did this several more times and it worked every time.


Sent my vector cut back to the laser to test my home position setup. Positioned a new sheet of printer paper on the table and hit auto focus. Up comes the table, up, up up,.... A mad dive for the power switch and just as I flipped it off there was a loud pop. Result- another crater in the vector cutting table plus this time the rollers holding the lens carrier rail popped out of the left side rail.

Being an experienced shade tree mechanic I loosened the three screws holding the side rail to the frame allowing the rail to move enough for the rollers to slip in place and then tightened everything. Ops normal, so I thought, except for auto focus and I can live without that.

Using the manual focus method I tried some raster engraving and vector cutting on small pieces in the upper left corner of the table. Everything worked OK so I thought I was home free.

A customer wanted another set of magnetic vehicle door signs for his second truck. Prepared the blank, sent the file to the laser, manually focused and hit start. Noticed that it was engraving at about half the power it should be so figured that I screwed up again and put in the wrong speed/power numbers. Thought I'd do a second pass and correct my mistake on the next blank. After engraving down about 2 inches on a 12 x 24 blank it started engraving at the correct power settings. Did this for about 4 inches and then back to half power for the rest of the sign. WEIRD!

Finally called tech support (after much flack from my better half who has no sense of humor about these things or appreciates a good challenge). After checking a lot of cable connection concluded that the ribbon cable connecting the auto focus probe to the main board had a broken wire in it. Auto focus would work when the lens carrier was in the right half of the work table (that's where I did all of my testing using my finger to depress the probe) but not when in the left half. When in the right half of the table the ribbon cable coming from the lens carrier was straight allowing the broken end to touch and complete the circuit. In the left half the cable is bent in an arc causing the broken ends to separate opening the circuit.
The squirrelly engraving was caused by the laser beam being out of alignment. Because I loosened the left rail to get the rollers back in place, the left and right rail were no longer parallel. It doesn't take much to get it off. Tech support talked me thru adjusting the rail and the aligning the laser beam so it strikes the center of the lens. Not hard to do but helps if there two people doing it. One special tool was required and that was an offset ratcheting straight slot screwdriver (4 in long with a 1/4 in blade). Have to get into some really tight places.

Now that everything is working normally again, I noticed that all the power and speed settings used on various materials are a bit high. Makes me think that the laser beam was out of alignment when I received the machine.

Lessons I learned:
1. Don't trust any function that has "auto" in its name.
2. Do not loosen any parts of the motion system before checking with some who know what they are doing.
3. Check the manufacturers website for updates to the manual. In my case there is 10 times more info available online than I received with the machine.

Was wondering if other Laser manufacturers do a beam alignment during the onsite setup for a new machine?
How often should a beam alignment be done? Or checked?
The tiny amount that I had to turn the alignment screws seems to indicate that just normal wear or just a little dirt on the rails and rollers of the motion system would put the beam off big time!

Glen

Keith Outten
08-09-2004, 7:59 PM
Glen,

I also suffered a near catastrophic failure that involved auto-focus, mine happend when using the rotary attachment. My manual didn't warn me not to use auto-focus with the rotary attachment and I punched a hole in an aluminum drink cooler as the table failed to stop on its way up during the auto-focus routine. Ouch!

Fortunately my machine didn't suffer any damage but I have not and will not use the auto-focus feature again. I did have to reset the springs on the left rail track (Epilog 24) but it snapped right back into place...all was well.

Kevin Dill
08-10-2004, 11:37 AM
Hello Glen,

I had to call your tech support today for quesitons on the Engavelab software. So while I was on the phone with them I asked the questions you were asking and this is what Kevin Huffman said.

Yes, if a technician was onsite doing an install and a beam alignment needed to be done, they would do it for no extra charge.

The beam alignment should be done when the laser does not engrave over the whole table. The easies way he said to see if it needs to be aligned is to draw 4 vector squares, put one in each corner and cut them out. Then look at the 4 squares that fall out. Make sure the cut is not slanted and that it cuts evenly in all 4 corners. If it doesen't then it is time to do a beam alignment.

Yes, if the machine is not kept clean it can help in the machine becoming out of alignment. Do the 4 square check every once in a while and go from there.

Kevin Dill

P.S. Kevin from Signwarehouse says Don't hesitate to give him a call anytime, he is more than happy to assist you anytime. And He is starting to get feeling of pressure from his other half also.

Gary Shoemake
08-10-2004, 3:33 PM
HI folks

I also spoke to Kevin from Singwarehouse and he also told me the same that Kevin Dills reported. One of the most important thing is before rach use make sure that the lens and mirrors 3 and 4 are clean. It helps to keep everything in focus. I have found that these folks are very reliable in their tech support and call backs. I have given Kevin from Signwarehouse the site address and maybe in the future he will be joining. ;)

Gary

Glen Peters
08-10-2004, 5:30 PM
Hello Everyone

Kevin fron Signwarehouse was the one that helped me with my mess. My experience with tech support people has mostly been with computers and the internet where the tech is asking questions from a script. Not so with the laser. Kevin listened to my problem and then we went right to work fixing it. Great job.
Glen