Lens cleaning and replacing

[fratres]

Having problems with read errors with the 400C laser of my V7, I tried to clean the lenses with glass cleaner, q-tips and alcohol. Most guides only give hints about the upper lens, but as the second lens (fixed in the sled beneath the upper lens between the coils) also gets dirty easily, I tried to clean it as well. After the cleaning the laser even worked worse, so I suppose I did something wrong, maybe pressed too hard. Taking a closer look at the lower lens I got the impression that it used to be coated (a darkpurple gloss at the sides and on the bottom side) and that this coat had come off in parts in the middle, leaving a yellow-purple mosaic on top of the lens. Suppose that´s the reason why the laser doesn´t work. Is that lens coated, are there any hints on how to clean this lens safely, and is this lens replacable without replacing the whole laser unit? It can easily be lifted and taken out after removing the sled with the coils, but can it also be replaced?

[cheryl771]

First thing. Always always always wear anti-static wristband if you open up your deck. Well you may have simply smeared around dust on the bottom lens. You may try cleaning it again. I don't know about coating but if it don't work already you can't make it worse. I suspect your laser is either on the way out or just plain out. Good luck.

[fratres]

Thanks cheryl, well I never used wristband, maybe good advice. I already removed the bottom lens, it´s just a tiny plastic lens, but I think I already did too much cleaning. Do you know if I can replace it with a clean and (maybe) regular coated lens of another dead laser?

[Warlock]

You can get new replacement lasers from foundmy.com.

[fratres]

I know, Warlock, replacing the whole laser unit is not the problem. I just want to know (as I think the lasercell, the mirror, the coils and everything else except the bottom lens is perfectly working) if I can replace this small lens. It can be lifted out of the sled, at the sides it is fixed with small plastic or glue pieces, but it fits in the sled so tight that a replaced lens should hold without further glueing, I think. Did anyone try this and does anyone know if the bottom lens is coated?

[Warlock]

I have never tried anything like this Fratres. Maybe Spedmetal or someone else can help.

[cheryl771]

I don't know that I would put the effort into fixing that. Maybe if you had a dead laser laying around but even then you would still have to clean it and get your fingerprints off of it just from putting it back in place. Wasn't that how this all started? Plus you have to be careful that you don't scratch the lens. To me I would just spend the money on a new laser and not deal with all these headaches.

[lufcfan]

I'd get rid and start over too :)

[spedmetal]

I have never replaced the bottom lens as it appears to be glued in and getting the correct position again after removing it I would think might be difficult. I have however replaced bad coils in a KHS-400C with the good coils of a worn out KHS-400B as well as the upper laser lens and it worked great.

It might in fact be that your laser diode is crapping out on you. Give it a try, what could it hurt. Get back to us with the results.

[fratres]

Thank you, guys. I will try it when I get a dead laser, don´t have one right now. So there´s no place I can get just the lense? And any info about coating?