Pay to repair laser with <15 min of use?

[romogracie]

Yesterday I bought a 1.8A laser from another LPF member (who shall remain anonymous until this gets resolved). I met up with him in person and verified the output with my LPM over a couple of minutes.

As soon as I got home, I did another 10 minute test with my LPM thinking it wouldn't be a problem due to the laser's massive heat sink. I have seen videos of similar lasers on this forum surviving 10-14 minute LPM tests.

After this test, I charged the batteries. Much to my dismay, the laser would not turn on after this. The batteries worked in another laser, so there was definitely something wrong with the laser.

I called up the seller and he said I would have to pay for the repair and that "there are no guarantees in this industry"... :wtf:

Do you guys think I should have to pay for this repair even though he claimed an unlimited duty cycle in his original sales thread? :thinking:

 

[tacomanmcjab]

HECK NO! You shouldnt have to pay a cent and this guy should repair you laser free of charge

... provided of course all the info you have provided here is factual

I do like the method in which you used to bring attention to this issue.

 

[RA_pierce]

Yesterday I bought a 1.8A laser...
I called up the seller and he said I would have to pay for the repair and that "there are no guarantees in this industry"...

Do you guys think I should have to pay for this repair even though he claimed an unlimited duty cycle in his original sales thread? :thinking:

At 1.8W output, that laser will be producing almost 7W of heat not including the heat generated by the driver.
I don't care how big the heatsink is, no portable laser dumping 7W of heat can run at 100% duty cycle without active cooling.

On top of that, there are few diodes that can sustain that power with a decent lifetime. These diodes are good for a bit more than 1W but 1.8W is pushing the limit.

That being said, I'm not going to say who is "at fault" especially since there is no clear diagnosis of what actually went wrong.

$0.02

 

[Delorean Geek]

I could go either way. On one hand when you buy a "home built" laser that there is no warranty...especially at that output. At 1.8A I am assuming you bought a 445 and are in the area of 1.7W-2W of output?...that's pushing a diode pretty hard and it's anyone's guess how long it will last.

On the other hand, you did just buy it. Was it new or a fresh build?

I can say on my 2W Jayrob I'm getting ready to assemble , I don't expect a warranty on such a modified laser. I do expect a warranty on the craftsmanship(like if the heat sink was cracked or the host had a build flaw) but as far as operation...these high output lasers are like race cars...you sacrifice reliability for performance.

Assuming you didn't put the battery in wrong, you probably just need to replace the diode.

EDIT: I just read your last line of text...he claimed an unlimited duty cycle at 1.8A?

 

[weidmark]

There is never a guarantee for how long the diode will last, even at lower currents. I agree with Delorean though, the craftmanship should be completely warranteed, but noone can guarantee how long a diode will last.

 

[romogracie]

I just read your last line of text...he claimed an unlimited duty cycle at 1.8A?

I forget his exact wording, but he claimed something to the effect that you could run the laser for about 80 minutes until the batteries died.

 

[Flaminpyro]

I would have to say yes you would have to pay for the repair since you ran it for 10 min stright, what would cause you to do this, were you trying to see just how long it would last ? I can see no reason what so ever to run a laser this long just shinning into a LPM !

No on the other hand as the seller told you it has an unlimited run time then he is at fault for telling you this and giving you a false sense of reason.

I think you both should split the cost of repairs you for doing such a dumb thing and him for telling you something that can't happen with out active cooling !

just my 0.02

 

[jakeGT]

I personally think I know who it is, who is making outrageous claims in the first place. ANd as a matter of fact, yes in his sales he mentioned being able to run the battery's (2 18650's for an hour and a half straight) his wording says RUN the laser for an hour and a half straight, but might have MEANT 1 1/2 hours of run time, not continous use.

But if it's who i'm thinking of, he's saying with aixiz 445 glass lens that at 1.8A over 20 lasers he has do over 1.9W, with no LPM.

Everybody thinks just because at 1.8A, your going to get 2W with a g-1. that's not true. AT ALL
I had a laser at 1.5A doing 1.2W

 

[JLSE]

I forget his exact wording, but he claimed something to the effect that you could run the laser for about 80 minutes until the batteries died.

I recall reading that statement somewhere in the past few days somewhere in the forum..

The idea of warranty is something that should be defined by the seller before hand.
I have sold up to 1.5W with a warranty, but only because the diodes in the units
were above normal efficiency.

I have also sold 1.8W, but do not offer a warranty on the diode, only the host
and driver... excluding the diode. Sales that included batteries and charger, I also
apply it to them. But again, as a buyer, its something to look at before hand.

An oversized heatsink does not mean that an LD will take sustained abuse, and
persons buying lasers at that kind of output should consider this going in to the
purchase.

At minimum id say the seller should offer to fix it for free, and the buyer cover
the cost price of a new LD... By cost I mean exactly that, no profit..

 

[hakzaw1]

I agree with Wannaburn and FP. Most like to be kind the thier lasers and 10 min non-stop has to be tough on any diode and/or driver with no active cooling.
BTW if you can get an agreed solution on this do you plan to 'push the envelope again' ---to me one do-over per laser, should be the limit.

GL to both of you.

hak

 

[qumefox]

I can see no reason what so ever to run a laser this long just shinning into a LPM !

I ran my 445nm labby for well over 3 hours just shining at a LPM. And I had my reasons. It was to see how well the converted CPU heatsink, (with fan) worked (quite well, actually)

Though I wasn't running it at 1.8A. It's been awhile but I seem to remember I had it putting out around 700mW during the test.

 

[JLSE]

3 hours is a walk in the park for a diode running @ .8A or so..

@ 1.8A, bonding wires randomly explode

 

[rhd]

In my mind it's simple:

- If you ran it for 10 minutes straight, that's on you.

EXCEPT THAT

- If he told you that you could do that safely with the laser he was selling you, then it's back on him.

 

[JLSE]

Found it... Thought that phrase looked familiar.

I am selling 1.8A (approximately 1.8W) 445nm lasers that can run non-stop for 80 minutes.
Check out my signature for the sales thread.

 

[RA_pierce]

Question:
Have we diagnosed the cause of failure yet?
Before we know what is wrong how do we even know if repairs will cost anything?

 

[romogracie]

Question:
Have we diagnosed the cause of failure yet?
Before we know what is wrong how do we even know if repairs will cost anything?

The freshly charged batteries work in another laser, so I'm 99% sure it's either the driver or diode.