Quest for a stable leadlight - New Images Posted

[LaserMod]

OK all, I've posted guides on how to re-align the diode, and up the current through pot and resistor modifications.

Now the final problem for the leadlights, my ultimate goal is to have a leadlight that is powerful yet stable. I think it can be done.

I have been studying MCA's this week and I must say I've got very interested at how the MCA converts IR to green.

The current is not a problem anymore, we can get it to 550ma with my resistor swap method (you can see the 221 replaced below next to the pot).

Our biggest problem now is heat, all lasers I have modified upto now can not stay at the power - they get warm within 1min of usage and thats where I see the value drop on my meter.

The MCA appears to be shifting because of the heat (I have verified by running the laser out of the casing - only the heatsink was the size of a brick and not portable anymore) so it appears to me even if we had a 500mw diode in there (which would mean puttin the diode on a lathe to get the factor to 9mm)the MCA would heat up quicker and we would be back where we started.

The first lense slides up and down the brass casing like a piston - can we not fix it in place somehow - what about superglue - I'll try it. [img]/ubbthreads/images/graemlins/thinking.gif[/img]





We still don't know the model number of the diode installed - does anyone know because Leadlight still haven't replied to my emails.

Just thought I'd post what I have found so far...anyone got any 'bright' ideas then? [img]/ubbthreads/images/graemlins/help.gif[/img]

[sharkeeper]

A stable pointer?

It will never happen. Even the CNI monsters have stability issues.

A cranked pointer is a ticket to disaster. I did mount a leadlight module that had a 1W diode in it and it was able to do 110mW fairly stable. The module was mounted in a solid block of aluminum machined for a snug fit and I used a 4x40 set screw to lock it in. A 123A powered the package and runtime at 700mA was acceptable.

Too bad I dropped it overboard along with my secchi disks and other equipment. [img]/ubbthreads/images/graemlins/mad.gif[/img]

Other concerns:

You can get a leadlight stable (or fairly stable) by getting rid of the pen body and mounting it into something with mass. Lots of coolth goes a long way unless you want to start to think peltier cooling.

If you want excellent beam quality and efficiency forget the MCA altogether and go with discreet YAG/Vanadate components. Of course alignment of these is difficult (and dangerous!) without the proper facilities and equipment.

Cheers!

[liteglow]

Lasermodifier What a Superb picture of the laser diode !!
do u mind that i copy them to my laser gallery !? [img]/ubbthreads/images/graemlins/smile.gif[/img]

[LaserMod]

yeah fine. [img]/ubbthreads/images/graemlins/smile.gif[/img]

[CliffS]

Yeah, maybe some kind of epoxy or something (just make sure its 100% right first [img]/ubbthreads/images/graemlins/smile.gif[/img])

Where do you find resistors that size??

[LaserMod]

www.uktronics.co.uk

[LaserMod]

Right, had some good luck at last! [img]/ubbthreads/images/graemlins/grinser2.gif[/img]

I have a 5mw Leadlight that outputs 58mw peak!

I swapped the first crystal, with three from other 5mw leadlights and the values were:

15mw - original abeland crystal
27mw - misc leadlight
8mw - misc leadlight
58mw - misc leadlight

And best of all I haven't swapped any resistors (yet) I think I might just leave it as it is with the pot at max - 320ma.

The stability issue stills exists but I get 2mins of constant power before it starts dimming - I think thats ok because there's always a strict duty cycle with these things anyway [img]/ubbthreads/images/graemlins/smile.gif[/img]

The diode is a 350mw replacement.

Posting some pictures of it soon, and hooked in with the meter for proof! I might stick it on ebay - anyone interested?

[LaserMod]

OK, here's the images:

This my new meter by the way (and was purchased on ebay):






Reading the 58mw:






A great shot [img]/ubbthreads/images/graemlins/grinser2.gif[/img]



I'm thinking of putting this up on ebay, but before I do that - has anyone got any offers here on CPF first?

And... here's a quick video of the 60mw in action - thanks to Liteglow for the hosting... [img]/ubbthreads/images/graemlins/grin.gif[/img]
http://stardust.as/crazy/albums/album149/MVI_0005.avi

[liteglow]

Hey no problem [img]/ubbthreads/images/graemlins/smile.gif[/img] [img]/ubbthreads/images/graemlins/smile.gif[/img]

haha u did`nt dare to shoot the laser into the cam [img]/ubbthreads/images/graemlins/tongue.gif[/img] [img]/ubbthreads/images/graemlins/tongue.gif[/img]

nice video btw [img]/ubbthreads/images/graemlins/wink.gif[/img]

[Lasernerd]

DO NOT USE SUPER GLUE!!
it will gas out and forever fog up your optics..

[Enigmahack]

I'm interested... [img]/ubbthreads/images/graemlins/wink.gif[/img]
I'm more interested in the combination of the crystal/diode you used, however I AM very interested anyway - let me know what price you're trying to get because if you're getting 50-60 mw out of that laser, and it's burning things, I think both of mine might be around 50...

[lasercrazy]

I think my leadlight might be around 50mw, it burns through bags and causes electrical tape to smoke. Hmm and I only thought it was around 30mw. [img]/ubbthreads/images/graemlins/thinking.gif[/img]

[Enigmahack]

that's exactly my logic - based on other pics I've seen before it only seemed like maybe 25-30 mw but if it burns garbage bags, electrical tape, etc.. Then I think mine may be closer to 40-50 or so. I need to get a reader I think [img]/ubbthreads/images/graemlins/wink.gif[/img]

[CliffS]

Thats freakin cool! Nice meter you've got there also. [img]/ubbthreads/images/graemlins/smile.gif[/img]

[LaserMod]

Yeah I was very careful with the camera [img]/ubbthreads/images/graemlins/mpr.gif[/img]

But good point Lasernerd I don't think I need to glue the crystals on the 60mw but on others that are not as stable...

I'd forgotten how superglue leaves residue because I once glued the focus adjustment in place...the next day the beam was all distorted. [img]/ubbthreads/images/graemlins/frown.gif[/img]

[cbfull]

I am confused. Did you actually have to remove the bare crystals?

Right in front of the diode there is a tiny plano-convex lens, and then what is after that. It looks like another lens because the Nd crystal should have a pinkish hue.

FYI, in my old laser (exactly the same guts as Leadlight) I accidentally put that little lens back in the brass module with the convex side closer to the diode. This was enough to stop the laser from working altogether. It came back to life at full-force when I flipped it the right way.

[LaserMod]

Sorry, I think I maybe getting confused between the crystals and the OC mirror.

I have swapped three parts - the diode, OC mirror and the crystal set as it is in the laser barrel - I have not separated the two crystals.

I think if I did that then it would be almost impossible to align the crystal set by hand and then get them fused together again.