Red dot not visible in Laserpro Explorer

[Abdul Baseer Hai]

Hello
I have a 50 watt explorer and am having problems with the intensity of the red dot pointer. The dot is barely visible and I am having a hard time aligning the machine in the relative mode.
The laser power seems to be ok but the red pointer is very difficult to see. I have to darken the room and position a white paper under the lense to see the red dot, even then it is a hit and miss.
Would appreciate any help in cleaning the source of the red dot.

Thanks

[Gary Hair]

If you are standing in front of the laser, it is in the back, bottom left corner. If you open the access panel on the bottom of the left side you will see it. It's hard to believe that it's dirty though, if it is then you should also be having problems with the laser too.

Here is a link to the maintenance manual, the red dot pointer is shown on a few pages http://www.meistergram.com/files/Man...10-20-2004.pdf, try page 24 first and see if that clears it up.

Gary

[Abdul Baseer Hai]

Gary,
thanks for the response.
I have gone through the maintainance manual and have located the red dot mirror. I cleaned that not long ago.
will do it again in the morning. Like I said that the laser power is not bad but the red pointer beam is extremely weak. Once I clean the collimating lens and the mirror and if it does not solve the problem, what more do you suggest.
What is the source of the red beam? It does'nt come from the laser tube, right.

Waiting for more help from you.
I am located 3 hours from the nearest tecnician stationed in Montreal and it is very expensive to get him over here.

[Richard Rumancik]

Abdul, it should not be too difficult to find where the red dot laser is located. If you know where the mirror is it can't be far away. It should be a small cylindrical device like a laser pointer. Perhaps it has gone bad - in any case you should be able to replace this yourself without the need of a technician as it is likely to be a minor repair. If it is not in your manual hunt around and you will probably see it. On the Mercury it is near the output of the laser tube close to the first mirror, but I have not seen an Explorer.

[Gary Hair]

The red beam comes from a diode, just like a laser pointer. Look on page 24 of the link I posted and you'll see #3, there will be two wires coming from it, that's the red dot diode. Check to see if it's clean, it should not get dirty unless you are in very dusty conditions. Check the output right out of the diode and compare it to what you are seeing. It's possible that the diode is failing, although I would think it would either work or not, not something in between. The mirror that the red dot reflects off of may be dirty, and you may not be hitting the mirror completely. First though, check the output at the diode and that may help determine what to do next. Careful of your eyes, it can damage them!

Gary

[Abdul Baseer Hai]

Gary and Richard,
Thanks to both of you.
Will get back to you as soon as I check the diode. I pretty much have and idea where it is located. Will try to clean both the mirror and the diode and will let you know
thanks again, this forum is a goldmine.

[Abdul Baseer Hai]

Gary and Richard,

I have completely examined the rear end of my explorer and here is my report:

1- I have cleaned the collimator lens (it was not dirty)
2- Found the diode (it is positioned perpendicular to the collimator) and is emitting a strong beam.
3- Cleaned the diode and the mirror it initially hits.
4- The intensity of the beam right out of the diode is much stronger than the beam at the other end (which is still extremely faint)
5- The power of the laser beam is still quite good.
6- 4 mirrors are common for the laser and the red dot. The only extra mirror is the one on which the red beam is initially reflected off of.
7- There is a small crack on one corner of this first red dot mirror. (the beam should be reflecting off of the center of this mirror, so the crack should not make a difference)

Now, as the final output of the red dot is still extremely faint, I need your help in determining what to do next.
Thanks

[Richard Rumancik]

If you put a piece of white paper in front of the red laser diode and you think it is working properly, then progress to the next mirror and do the same. You need to figure out what is causing the loss in intensity. Perhaps it is misaligned and not all the beam is getting through. The other possibility is a dirty or bad mirror (a bad spot that is not reflecting properly). When you take the lens out, can you see a red dot on the table? It may be fuzzy but should still be so intensity there.

There will be some drop in intensity with distance and each mirror but perhaps you can detect the point where the problem occurs.

[Gary Hair]

7- There is a small crack on one corner of this first red dot mirror. (the beam should be reflecting off of the center of this mirror, so the crack should not make a difference)

The red dot actually hits the edge of the mirror instead of the center, it's how the two beams align. Hold a piece of paper on that mirror and check where it hits, if its on or near the crack then you may have your culprit. If not, follow Richards advice and check at each mirror with paper to see where it's losing strength.

Gary

[Abdul Baseer Hai]

will get back to you a little later.
Have to go see a client
Might be a little difficult to place a paper before the reddot mirror and see the red beam as the mirror is located at an awkward to see angle
will try and let you know

abdul

[Rodne Gold]

Have you tried adjusting the red beam mirror? The red beam is probably out of alignment and not hitting any of the other mirrors properly . Don't adjust the other mirrors if the laser is still good. You will put it out of alignment.

[Abdul Baseer Hai]

Hello all,
I have been trying to identify the problem through a process of elimination. Here is my report.
The red beam appears to be quite strong coming out of the diode.
I have put a white paper in its path and the beam is still visible after the second mirror (mirror in the top left corner)
The intensity drops just before the third mirror (bit is still visible)
The intensity drops considerably after the third mirror and before hitting the final mirror, before the lens.
After the lens, the beam is barely visible and I have to dim the room lights and strain my eyes to see it.

As Rodney suggested, I have not re-aligned any of the laser-mirrors and have also not touched the red beam mirror (as the beam is travelling right to the end, albeit, with considerable loss of intensity.
My question now is that could it be a failing diode?? If yes, then how difficult is it to replace it. As Rodney has the exact same machine, I hope he can guide me through it. Are there any alignment issues when replacing the diode??

[Gary Hair]

If the beam is as strong as you say it is coming out of the diode then I'm not sure replacing it will solve your problem. If you remove the diode mirror and the first mirror you should see the beam hitting whatever wall it is pointed at. Unless that wall is very close, or very far, you should get an idea of how strong the diode really is. If possible, I would turn the laser so it points at a wall 8-10 feet away, if the beam is bright at that distance then the diode is probably fine and there is something else wrong. Unfortunately, I have no idea what could be wrong.

Gary

[Rodne Gold]

I'm pretty sure it is a red beam alignment problem , either that or the lens on the diode itself is contaminated or has suffered a mishap (but then the beam would be blurry) You can try adjust the red beam mirror (the silver ordinary mirror) , you can also replace it with mirror acrylic or ordinary mirror , it's nothing special.
The red beam diodes aren't at all expensive anyway...

[Abdul Baseer Hai]

Is there any special alignment procedure after replacing the diode?? I will try to move the diode mirror up or down slightly and see what happens.
Also, I will try to guage the intensity of the diode by following Gary's suggestion.