HELP - noob trying to repair laser pen

[tsteele93]

Sorry for the double posts, wasn't aware that was bad etiquette. It will never happen again!

I paid $40 shipped, so no big deal.

Here is the update...

The laser works. I put it all back together and if works. The problem IS the protected batteries. As I screw them in, the module starts coming out the top of th pointer. I need to get unprotected batteries and tighten things up (I used tin foil wrapped around the module as a way to make for a snugger fit) and I think that I will have a nice $40 (shipped) laser pointer. I will check the output with the laser bee A when I get he batteries.

It is a slightly flawed design being case negative and no hump to contact the negative end of the battery. I learned a lot so it is well worth $40 for that.

I also have a circa 1992 sharper image (LYTE OPTRONICS PLP7NE) 5mW pointer in pieces that I am going to play with and see if I can try its lens (appears to be glass) and get any improvement. Also the sharper image pointer has a driver with a variable pot that might be worth playing with. I'd at least like to put it on a meter and see what it can put out.

All in all, starting to look like it may turn out ok.

I think the original seller was not trying to scam me in any way. It is an odd build and if the power is close to advertised then I am ok with it at that price. What do you guys/gals? think?

EDIT: Note, I did not double post! I just noticed that my old sharper image pointer (~400 if I recall) ran off 2 x AAAA batteries. Yes, AAAA! The case is very skinny!

I'll post pics later.
ts

 

[rhd]

Hey, if you paid $40, that's not a bad deal (especially shipped). ~$30 for that laser is about the part cost, so it's tough to complain.

Those AAAA batteries are tough to find eh ?

 

[HaloBlu]

If you need AAAAs, 9volt alkalines have 6 batteries inside that should fit. They are 3.5mm shorter. Same voltage & lot cheaper then AAAAs.

 

[Wolfman29]

Hey guys.

Just so you guys know, I am the original seller

@RHD: I *did* say that the DRIVER would last longer on-time with lower-voltage LiFePO4s due to less drop-out. However, after testing on the driver design (really basic LM1117 build), it can handle about 30 seconds on time with 15 seconds off time, which was the duty-cycle recommended for this build with standard, 4.2V charged, li-ions.

I suppose I should have clarified - non-protected batteries are a must for this laser - it's a rather tight build.

Anyway, yes, it should output at or above 210mW of power because I LPMed it at that

As to why tsteele didn't just reply with a message to me (I responded to the PM he sent me only two hours after he sent the PM to me), I don't know All I know is that I told him exactly how I would have repaired it, and I didn't get a message back.

Regarding heat problems... the driver does get warm, but the module, if put in properly using a solder contact, actually acts a pretty good heatsink itself. It's nothing like a big hunk of aluminum, but these pens aren't meant to have long duty-cycles. That's not how I built them. They are built to be glass cannons. On for a few seconds, burn holes in too many things, and then shut down.

Anywhoozle, I am glad that it works now. My preferable method for making sure there is a nice tight fit in those pens is a bit of solder on the module (preferably not near the diode), and then filing it down to get a pressfit. It works splendidly, and you will all see it in the future with my growing pen collection I am building ^_^

@Lazeerer: I may have described the method I use to get at the bottom of the cell imperfectly, but the method is tried and true. One simply rips out the line from the positive to the protection cell, removes the cell protecting (pretty straight forward - just get a nice quick cut), and cuts out a little bit of the battery casing near the bottom so it can make nice contact.

EDIT: I just realized that he removed the the driver board/spring contact/button from the pen -.- It's going to be DAMN hard getting that back in.

EDIT 2: I also have an identical pen in a chrome LeadLight that works wonders... exactly the same, down to the resistors on the driver Works fine and dandy. I get about 30-45 seconds of on time before I get reduced output.

 

[rhd]

@RHD: I *did* say that the DRIVER would last longer on-time with lower-voltage LiFePO4s due to less drop-out. However, after testing on the driver design (really basic LM1117 build), it can handle about 30 seconds on time with 15 seconds off time, which was the duty-cycle recommended for this build with standard, 4.2V charged, li-ions.

That makes a *lot* more sense. I was trying to figure out what sort of driver there would need to be in order for the batteries to impact diode life. The only thing I could think of was "no driver" or "direct drive". Otherwise, the diode shouldn't care what feeds the driver. Alrighty, glad that brain puzzle is cleared up.

 

[Wolfman29]

Yeah. In my tests with a voltage of 3.6V, I was able to get up to a minute on with 30 seconds off.

 

[tsteele93]

As to why tsteele didn't just reply with a message to me (I responded to the PM he sent me only two hours after he sent the PM to me), I don't know All I know is that I told him exactly how I would have repaired it, and I didn't get a message back.

All you told me was that it was "odd" that the module was coming out and how to put the module back in. If I had fixed it as you suggested and put the protected batteries in, the same thing would have happened again.

In this thread I was getting to the root of the problem.

Anywhoozle, I am glad that it works now. My preferable method for making sure there is a nice tight fit in those pens is a bit of solder on the module (preferably not near the diode), and then filing it down to get a pressfit. It works splendidly, and you will all see it in the future with my growing pen collection I am building ^_^

I wrapped it with some aluminum foil until I got a tight fit.

EDIT: I just realized that he removed the the driver board/spring contact/button from the pen -.- It's going to be DAMN hard getting that back in.

I thought it went back together nicely. I'll post pics when I get unprotected 10440's.



ts

 

[Wolfman29]

Hmm. Sorry I didn't explain better then. Anyway, apologies for the miscommunication and the problematic module. But, I am glad it all worked out and that you learned something in the process!

I hope you like the laser. I'd love to see some pics once you got it working

 

[lazeerer]

Glad everything worked Out.

 

[tsteele93]

I tested the laser tonight. I have kludged it together to work with the longer protected Li-ion batteries. I did some cutting into the end cap and a few other things designed to effectively lengthen the battery compartment.

Anyway, it doesn't look bad and it works.

The beam is very tight for the most part, it does have some splash.

The power is a respectable 205mW on my laser bee A, which isn't shabby for a $40, pocketable pointer.

ts

 

[Wolfman29]

Well, if it worked for you, I'm glad it worked. Good luck and be safe! :cheers:

 

[tsteele93]

Yeah, it will definitely smoke anything dark colored from even a couple of feet. It is a nice little burner for the money.

ts