Is it me or the lens?

[zhxwn]

Hey, I just received my SF501b, however when I turn the lens at the end, there is no change in the beam, even when I take it off completely it still remains the same.

At 1 foot the 'dot' is about 8 inches wide, at 1 meter it's about a foot wide. I've read that blue diverges a lot more than other lazers, but surely I should be able to notice a difference when tweaking the lens?

I believe it uses a 3 element lens, I'm not complaining about the product, I'm new to this so I am still learning and would just like to know if I am missing something?

Thanks

 

[Laser Chick]

There is something not set correctly because that is wider than a flashlight beam. It should be about 6mm wide at the most at 1 foot away. Does the lens look really dirty or damaged? Did you email the company you got it from? They will be able to straighten it out for you. Send pictures along with your email as images usually are very helpful.

 

[zhxwn]

Appreciate the reply laser chick! I'd give you a rep if I knew how!

Here are pics if anyone wants to see









Note: the shape of the 'dot' does not change when I twist the end, it stays the same no matter what. The twisty bit at the end has nothing in it, I had a feeling there would be a lens inside that when I twisted it would adjust the beam.

Thanks again

 

[BowtieGuy]

Check the simple things first, are you sure the lens itself is being adjusted in and out, and not just the focus adapter.
Is the lens housing in backwards?
Is the lens itself even in the housing, it should change somewhat if you have a lens in place, even if you can't focus it properly.
Remove the focus adapter, and see if you can screw the lens in far enough to get a better focus.

 

[zhxwn]

Hey bowtie,

I can tell you 100% that nothing changes AT ALL when I turn the focus adapter. It could be worse, but I'm positive that if I could change the focus I would be able to get better results.

I do not want to fiddle too much as I'm new and don't want to damage anything, but I will try to do as you suggested, and check the things you mentioned, thanks!

 

[zhxwn]

Guys!!! I have fixed it!!

I took the lens focuser off, twisted the other bit and noticed that the dot was changing.. I adjusted it a bit more and BAM. It's a dot. It's a wonderful blue dot!



Ok ok... I've learnt more about operating a laser and sorted mine, I am very happy, thanks Bow and Chick!

Thread closed!

 

[TaterMay]

Yea, I see what looks like a single element lens in there. Sounds like your lens wasn't screwed into the focus adapter tight enough, so your focus adapter was just basically spinning around on the lens. Take the lens out, abs screw it into the focus adapter until it is nice and tight. Then, you will be able to use your focus adapter to screw the lens in and out.

 

[BowtieGuy]

Glad to see you got it fixed, and learned a little about your laser at the same time.

 

[Pman]

Yup, Bow nailed it. I knew that was it as soon as I read it. I've had this happen so many times because I didn't tighten the lens tight enough to the lens nut ie focus knob. Sometimes if you are using a tight spring it will hold the lens and this will happen. I can't stand a focus knob that is loose.

 

[APEX1]

I new that was the problem as soon as I seen the pics. Glad you figured it out!

 

[nikooo777]

Is there some trick or hack known here at LPF to actually avoid this issue at all?
I have this issue often as well and i find it frustrating to take out the element to just screw the ring in properly again...

 

[TaterMay]

Is there some trick or hack known here at LPF to actually avoid this issue at all?
I have this issue often as well and i find it frustrating to take out the element to just screw the ring in properly again...

You mean the lens coming loose from the focus adapter, right? Because it kind of sounds like you're saying the actual element is coming out of the lens frame.

If so, I would say just a tiny dab of super glue on the threads would be sufficient. Just a wee little drop so you can get it off if one day you need to for some reason. If you go this route, you would have to be incredibly careful because if it got on the lens, it may very well ruin the lens. If you're talking about the actual element, I am of no help. Lol.

 

[Pman]

I just finger tighten really hard and that does the trick or try a different spring if it seems to be catching the lens. It would certainly work to add a drop of glue but that would stink if you managed to get it on the lens. Don't know if using nail polish remover would cause an issue with the glass or coating if it has one.
You could of course use a tiny dap of thread lock but I think a lot of people use the white thread tape. You must not allow any of the tape to come loose so triple check. Don't like the idea of using it on the diode side of the lens because you are going to keep moving it and it could come out of place and the beam could hit it.

 

[zhxwn]

It seems to be working perfectly now, thanks for the advice though Pman, I'll bare that in mind if anything plays up!