Guessing the power

[Dan_from_Van]

My second ever laser arrived (the first was a tiny <5mW 405nm pen).
Ordered it from Aliexpress at around $15, it's one of those Laser 303's hosts with a 532nm DPSS running on a single 18650, 4200mAh 3.7V.

My question is:
What do you think is this laser's actual power?

After (in some cases even without) focusing, the laser is able to:
- cut shallow scratches into hard plastic, which are noticeable with a finger touch;
- light a match (with a vanilla match head, didn't paint it black) in approximately 1.2395 seconds
- burn tiny holes into black dry paper
- burn tiny holes into a thin and dark coloured plastic

During daylight, the beam is barely visible, as it gets darker, it shows up as a very thin beamie.

The reason I'm asking is, I'm thinking of buying a 488nm 150mW Challenger from Sanwu, and I'm wondering if a 150mW 488nm would be able to perform better than my cheap 532nm.

My guess, according to some googling around, is it may be 70mW.

Thanks in advance to everyone

 

[Nexgen]

You can’t tell exact power without proper “Laser Power Meter”, you can only guess as you did. These pointers are anywhere from 50-90mW. 488nm 150mw will be a nice laser. I have 60mw 488nm laser, which has a decent beam. You can’t go wrong with Sanwu, their quality is top notch. I had four handheld lasers from them.

 

[Dan_from_Van]

You can’t tell exact power without proper “Laser Power Meter”, you can only guess as you did. These pointers are anywhere from 50-90mW. 488nm 150mw will be a nice laser. I have 60mw 488nm laser, which has a decent beam. You can’t go wrong with Sanwu, their quality is top notch. I had four handheld lasers from them.

That's definitely nice to hear. Do you think that 488nm 150mW will have a more visible beam than the 532nm I'm using?

 

[paul1598419]

First of all, that 4200 mAh claim on your battery is ridiculous and is seen on many crapfire batteries. I would be surprised to find its capacity is 2000 mAh as that is unlikely as well. The 532nm laser is likely somewhere between 50 mW and 80 mW. I have several that measured ~80 mW, but also have a couple ~50 mW. If you are interested in getting some good brand new batteries for these, try liionwholesale.com. They have some on closeout that are under $5.00 each and are 3000 mAh.

The only way to learn the exact power of your lasers is to have them measured with a calibrated LPM. I have measured powers for members here in the past if you are willing to pay shipping both ways.

The 488nm laser is going to be at the edge of its power at 150 mW. I have one of these that is over 100 mW and it is quite visible. If it is a true 488nm it will look blue and not cyan. These Sharp diodes can end up anywhere between 487nm and 492nm.

 

[GSS]

Your 488nm at 150mW should be about 65% as bright as a 70mW 532nm
At 150mW with a tight focus it will burn better because of the power even though a little dimmer. At this point at 150mW it's more about the beauty of the 488nm color than burning though. 500mW is probably the minimum if you want to start playing with the thought of burning.
Do get some safety glasses while your at it when ordering from Sanwu.
Sanwu makes a nice unit so enough it

 

[GSS]

Let me double post here, a 405nm at 500mW will be the best burner because the 405'a have the tightest spot when focused well but the beam will not be visible.
I'm mentioning the 405's as it's probably the cheapest bang for the dollar.

 

[Dan_from_Van]

Thanks for the replies.

Even though the prices are good, liionwholesale.com don't seem to be shipping to Europe. So I'll probably order a better battery from some local shop, knowing how bad the current ultrafire is.

Can the batteries from Sanwu be trusted or would you go for a branded one in this case as well?

 

[GSS]

Looks like Sanwu carries top notch batteries like AW's and Pansonic's and LG's so your good. Also looks like the only 10440 he carry's are Trustfires but the only other maker of 10440's so far that iv'e seen are Efest which are a bit better but you should be fine with those 10440 Trustfires if your laser calls for it. Thing to consider is that Sanwu units tend to be battery sensitive, meaning that only "button tops" or "protected" fit their builds better so I would go with them just for that also and ask them when ordering.
Even though your so called 18650 4200mah Trustfire isn't a true rating they should be fine with your 301 style 532. Just don't leave them on the charger long or all day or night..

 

[Immo1282]

If I may interject with GSS on ordering a laser with batteries from Sanwu - this is generally not a good idea as there is way higher chance the laser will get stuck in or confiscated by customs. If the laser has no battery in the package - a customs officer won't be able to power it on, so even if it does get inspected, it'll likely be repackaged and sent on instead of confiscated.

I'd do some googling - A lot of Li-ion cells have become more avaliable since the introduction of vaping as they're powerhouses (so good for powering hungry laser diodes as well as huge vape units)

 

[paul1598419]

I have found that the batteries you can get as accessories to lasers aren't usually as good as the ones you can buy from online sites that just sell batteries and chargers. There have to be some in EU that you can order from. Sorry, but I don't know of them as I am in the USA.

 

[hakzaw1]

GOOD advice Immo
IF you lose your laser to customs AND the batts were in the same box... you will have different feelings about saving a few $$ on shipping ..
aside from what has been said..
Do want someone with NO LASER understanding to put the batts in your laser? (NO)
Will he/she know anything about duty/rest cycles- (NO)
-will someone there get injured? (possibly)
Some members when ordering a laser that comes with free batts have requested that the seller just keep them. (like me)
Will they know or give a rat's ass about POLARITY (NO )

and ... as said (sorta) free batts are often not worth what you did not pay for them--& that is pretty bad.
Same for the free Li-Ion chargers.. think about that-- even JETLASERS sends very cheap chargers ..I call them 'travel chargers' & suggest using them VERY carefully..

be smart and get a smart charger.. you can get a smart Nitecore for around 10$usd..

__________
a good LPM is needed even by old pros..
example-- same 'color' red- one is 1W 640
the other is 2W of 650.. which is 'brighter'??
neither theY look ABOUT the same.. so even if they are the same 'color'
A guess is just that... a guess. as said for most humans 555nm 'looks' the 'brightest' compared to any other laser w/ the same mW.

also to double 'perceived' brightness you need 4 X more mW--2W is NOT twice as 'bright' as 1W at the same nm .
...it takes 4W and so on.
crazy uh?? it takes 16W to double a 4W ('brightness' by eye.)
Of course the wavelengths matter a LOT.. a 405 that can burn a hole quickly in a black plastic bag LOOKS kinda harmless at 100mW-- but it is a fast burner.. the very thin beam helps a lot and that makes the 405 the most dangerous of all visible lasers(IMO). ( EVEN A 1$ 405 POINTER)

 

[paul1598419]

@ hakzaw1

Len, I was wondering if you ever got the grating I sent to you over three weeks ago? I can send you another if you somehow didn't receive it. I would want to double check your address first, though.

Speaking of brightness of lasers at different wavelengths. I recently finished a 465nm laser that measure 1.77 watts. It looks very similar to one I have that is 445nm at 2.2 watts, but is brighter than the 445nm one. The 445nm one burns better than the 465nm one, but it burns pretty well at just under 1.8 watts.

 

[RedCowboy]

@ hakzaw1

Len, I was wondering if you ever got the grating I sent to you over three weeks ago? I can send you another if you somehow didn't receive it. I would want to double check your address first, though.

Speaking of brightness of lasers at different wavelengths. I recently finished a 465nm laser that measure 1.77 watts. It looks very similar to one I have that is 445nm at 2.2 watts, but is brighter than the 445nm one. The 445nm one burns better than the 465nm one, but it burns pretty well at just under 1.8 watts.

BURN ?? With a laser ? How uncouth ( Not really ). You better be careful paul, you may start to enjoy it.

 

[paul1598419]

Yeah, I have a piece of plywood that I use just for that purpose. I don't care about that property, but realize that others do. It had been awhile since I built a laser powerful enough to burn wood. The last being the 1100 mW 520nm one. It could also burn, but of course at just 1.1 watts, not that well. I usually do the burn test with any new laser that might qualify.

 

[RedCowboy]

So I guess my 9 x nubm44's all focused and converged to a point burning and cutting this and that would not impress you ? To be fair the way the smoke jets through the beams is a pretty effect although I have to watch it on playback to see the full effect, however you can see the beams through your attenuation safety glasses when up close and the air is thick with smoke, have you ever noticed that ?

It's kind of like how a foggy night eats up the power in a shorter distance, but the beams are extra bright, I just love 405nm beams in the fog, I have always liked dark red beams but that 405 is almost magic especially when it's highly visible, I still want to build a multi beam 405, and yes I would burn with it as well as enjoying the pretty beams.

 

[paul1598419]

We have had particularly foggy nights here lately and I was surprised at how little they helped increase the beam's visibility. I only do a burn test once, so no, it isn't that important to me. If you enjoy burning wood that is fine. I just got bored with it a long time ago. Unless the wind is still, you might not see much smoke except at the point where the burning is taking place. I have lived in places so windy you can't see the smoke from a campfire.