replacing bulb

[Cheryl Holmes]

Just a quick question before I go spend a lot of money, when I had my machine serviced back in July I was told I was running approx 19 to 20 watts, I have a 25 watt machine..It has been running pretty good, a few items I had to lower the speed on I mostly run acyrlic..I was running some plastic signs, it was cutting through the black pretty good and white under layers was pretty clean but when I started to cut them out, there were 12 items the first 4 cut great, after that each one got worse by the time it hit the last one it was barely making a line you could even see and the last one nothing...I ended up having to run only two at a time they are only about 3"x2" bears and it took almost twenty minutes for two because I had to slow the machine down...I am sure I know the answer, but before I throw out 800.00 or 900.00 dollars I wanted to check with the experts because of course my salesman is going to yes that is what it is...I have a vanguard 2001, which are service my universal, 25 watts I was also wonder if the price they are quoting is right or pretty close...any help would be greatly appreciated....

[Mike Christen]

Hi Cheryl

Check your cooling fans and be sure they are all running full speed. Also check your tube cooling fins, be sure their clean and there are no obstructions blocking air flow. Overheating could reduce power output the hotter it gets the longer it runs.

Try running the last item first and see if it cuts OK, if not it may be a beam alignment issue.

Sounds like the tube is going bad if its only putting out 20 watts.
Hope this helps

[Cheryl Holmes]

After reading some older post, I got to thinking like what you said it might be getting hot...I have never open my machine always afraid I will break something, so this morning is the first time I open the back and was not sure where the tube was I seen a mother board it look like and a couple other box in items and I stopped, afraid I would mess something up so what are the fins I have heard this a couple times and where are they and better yet where is the tube...I am sorry for asking so much, but it is time I learn if someone can help me out a little how to check these things...instead having a service call for something I can do on my own...thanks again for your help

[Rob Bosworth]

Cheryl, the laser is the silver box that runs along the back of the machine, under the cover. The UL laser has two fans on it, that blow and suck air directly out of the back of it. I wouldn't guess that you will be able to get too much dirt out of it, but a good blowing out won't hurt it.

I would check the alignment of the beam. If you run the system at full power for 10 or 15 minutes, pause the machine, then feel the backs of the mirrors and mount for the lens in the motion area of the machine, to see if any of them is/ are getting warm. If the optic has warmed up, you either have an alignment problem or a bad coating on one of your optics. A lot of the time, if you have an alignment problem or optics going bad, the build up of heat will change where the laser is pointed. Also, the further you are from the laser, the more the heat build up will effect your laser processing.

Good luck.

[Richard Rumancik]

Cheryl, you are correct to be cautious but you should not be intimidated by your machine. Try to get the manual which shows all the parts identification and location. If you are concerned get a technically trained friend to help you open things up the first time. In the mainboard area, you do need to be careful that you don't cause any static discharges onto the board or components. The best way to discharge your body from static is by touching a grounded piece of metal in the area (like a conduit, water pipe, metal outlet cover etc, grounded housing of a power supply etc.) before you poke around.

I don't know your machine, but the laser tube will probably be a rectanguar shape maybe 4-5" square and perhaps 36" long. Usually they will be mounted at the rear, middle or low down, running left to right. There may be an access cover at the rear for this. Usually there are several flat fans blowing over the tube to cool it (high power units use water cooling; yours will have fans.) The fins are basically metal rails along the length of the laser tube that increase surface area. The heat from inside is transferred to the fins, then the fans remove the heat from the fins.

It would be advantageous to get comfortable and familiar with the parts as it will reduce costs for repair. You also need to be able to do alignments. If a mirror got loose and is not aiming right you might get enough energy to cut but it is obviously not right. Do you have a red beam? Is it getting to the workpiece properly? If the red beam is fuzzy or missing the alignment is probably off.

Hopefully it is not the tube, but if it is, $900 to repair the tube sounds like a good deal. Usually it runs more than that.