WTH Newwish, you use your brain!?

[brtaman]

Hello,

I will begin this story by describing my NewWish True 50, bought of DX. Well to begin, I was really surprised by the output of this laser, I was getting a bit worried reading the gamble with these DX lasers, but I seem to have scored a good one. Well now to the problem, the laser heats up very rapidly and starts going TEM1+ very quickly noticeably two beamed, this to me was completely unacceptable (im talking 10 sec and it would mode hop).

Well I decided that it just wasn't going to cut the mustard and proceeded to ripping the laser apart. Getting the front cap off was a royal pain in the ass (it just wouldn't budge), so i proceeded to cool the cap down to -40 ish, upon which it slid out no problem.

I had always assumed that the pen style casing had acted as a sort of make-shift heatsink (after all you can't run a 500mw IR diode, with a couple of grams of bronze now can you? Well to my surprise, the module is suspended in mid air... It has a nice buffer of a very good insulator (air), between it and the casing. Now I am wondering what kind of an idiot company could not see the potential of producing much better lasers with not additional cost to them!?!?! I mean all it would take would be a slighty (.5mm on each side) smaller internal tube diameter...with this the module would be MUCH better heasinked which would allow much better beam specs for an increased amount of time.

What one with such a penstyle DX laser could do, is just buy some aluminum tape wrap it around once or twice pop (push would be required due to the tight squeeze) the module back into the laser and enjoy much better run times...This was my initial plan, but I was so utterly disapointed in the internal mechanics of the laser that I decided to just ditch the casing and proceeded to vastly improving the cooling and therefore vastly increasing the run time of the laser.


*****Rant over*****


What I decided to use for my project was my old blu-ray host with the addition of a huge slab of copper I had lying around (130g's of copper like to see you heat that up diode hehe).

The copper was drilled into and precision filed for a "perfect" fit for the module. This is going to be doing all the heatsinking.

After I had the fit perfectly tuned (an aixiz module, the rear) was used for measurement as the diameter of the modules is the same.

I popped the green module into the copper, used a gracious amount of arctic silver (you can see it in the picture, hadn't cleaned it up yet), after this was completed the module was fastened on both sides by a hot glue gun (good bonding yet nothing permanent will allow me to modify design in the future). Since this was a project designed to increase the run time of the laser, I also added a small heatsink to voltage/current regulator thingy (yeah im all science ;D), it got pretty heated when I was testing the module, so I said why not.

The project itself was alot easier that I thought it would be on the power supply side of things, the module was prefect. Not only did the copper piece fit perfectly into the module, the length of the driver and spring(negative), meant that the only mod on this side would be to flip the battery pack over. The positive side was also extremely easy to get, just soldered a wire to where the spring was and connected it to the case (wow! ). Since the host has its own switch and I was in a lazy mood all I did was jump the connection on the driver, again easy mod.

So with the electrical and mechanical parts completed I proceeded, to putting the entire thing together. Here is the newly completed pointer. The foil tape wasn't necessary but is there to ease my mind, and to make it look more scientific ;D

A shot of the pointer in my hand for size reference.

The result???

Well the I can use the laser for about as long as I want. The longest I have done it for so far is around 10 minutes. During this time the laser did not mode hop, the beam stayed nice and thin. What surprised me the most was the heat. After the full 10 minute run I had a really hard time discerning whether the heat of the heatsink was from my hands or from the diode. The heatsink was doing an amazing job. Overall I am very happy with my pointer now, its stays TEM00 for as long as I want and shows no sign of hopping or anything.

I believe that the time I spent on this mod was more than worth it. However, for those of you with these NewWish pen lasers, who do not want something that looks like what I did and prefer the look of the original host, then I would highly suggest some foil between the module and the host, for longer diode life and a much better duty cycle, but be warned the front cap is a fighter, it took me forever to get it off, dunno what I would've done without the cooling system.


Thanks
brtaman

 

[Murudai]

Ha ha, lol. Great thread

Lets us not question the 'wisdom' of dodgy laser manufactures, they truly are a random force in the universe

 

[brtaman]

Lets us not question the 'wisdom' of dodgy laser manufactures, they truly are a random force in the universe

Very true murudai words of wisdom!

I guess the problem was with my "optimism" in thinking that even if they produce cheap lasers, they must at least have some common sense. Well that optimism has now flown out the window, at least now I know that kind of "skillful engineering" to expect from a company such as newwish, but on the other hand I am very happy with the way the module works with adequate cooling. The beam is as thin and nice as the one coming out of my Aixiz labby, also divergance is very good. For 54 bucks I am quite satisfied, if a little bit annoyed, as it would cost them the same to manufacture a smalled inner diameter host yet would get rid of the main deficiency of their pen style lasers...


brtaman

 

[diachi]

Great mod, saved you having to RMA you laser aswell, maybe other people will follow suit.

Diachi

 

[IgorT]

Well to my surprise, the module is suspended in mid air... It has a nice buffer of a very good insulator (air), between it and the casing. Now I am wondering what kind of an idiot company could not see the potential of producing much better lasers with not additional cost to them!?!?!

Haha, well, i also thought they were retarded, when i first saw the air (or plastic in some cases) heatsink..


But guess what. They don't do it out of stupidity. They do it on purpose!


I've taken appart my DX200 pen, and decided to put it into a body with great heatsinking - the Rominsen L-D030. Well, a body with great potential heatsinking, that is - it also has an air heatsink inside.

So then i mounted the DX200 module into that body. The modules have the same thickness, meaning no touchy touchy with the body, so i had to put something in between - i used very thin aluminum with a thin layer of heatsink paste.

The laser was peaking up to 160mW before, i expected it to go higher, and be more stable.. But after it was heatsinked properly (and i could feel the body getting hot outside), it would then only go to 110mW, if i was lucky! If i left it on so long, that the body started getting HOT outside, well, then it would slowly climb.

After i removed the heatsink, and put the air back in, it was again peaking at close to 150mW, but dropping soon after.
It took a lot of heatsink tweaking, to get it just right. Too much, and it would start very slow, too little, and it would peak and drop.

After like 10 attempts, i got it to peak at 140mW, and stay above 130mW for a while.


And this was just one of them. Another might behave the opposite way, and work best after taken from the fridge, the third might come out of the fridge at 5mW.



Anyway, if they heatsinked them all properly, then the powers they do would be much different. The manufacturer just wants a high peak, without caring what happens later, and this is how they achieve it.

As the heat climbs, the crystals soon reach their max efficiency, but as the heat clims futher, the efficiency starts dropping again.

 

[brtaman]

Yeah now that you mention it, it does seem perhaps a bit dimmer, but I usually just leave the coper part in my hand to warm up the laser and then lase with it...perhaps this could be the difference?

But in either case, I much prefer, having a bit less power and a nice thin and stable beam, its not powerful enough to pop anything, anyways ;D Maybe ill just pot mod it to get it up to spec? Its an experimental greenie in any case.


Thanks
brtaman

 

[IgorT]

Well, depending on the laser the peak power can go down in this case, but it becomes more stable (slowly climbs), or it can actually peak just as high, but become stable (and drop more slowly).

In both cases, stability is the result, but it's up to the crystals/alignment/whatnot, what stability will mean.

 

[brtaman]

Yeah, that is true...depends on the module, and newwish builds their laser with a high degree of variance, you can get complete crap or an actually very decent laser.

But I do agree with you that it would seem the only reason for lack of heatsinking, is the quick high peak...sad really but for 50 bucks for ~50mw you can't really complain though hehe


brtaman

 

[Petrovski]

Very nice mod. That's one giant chunk of copper heatsink.

 

[Maven]

i am thinking about doing something similar with aluminum if i can ever get mine apart ... i think i am going to have to use a dremel tool

 

[brtaman]

Hehe petrovski, thanks...it is a huge slab of copper isn't it ;D

Oh and maven if you want stability out of your laser then I highly recommend it, just be prepared for a longer warm-up time...but then it is stable for as long as you want...yesterday after a 15 minute session, I finally felt a little bit of warmth from the heatsink However, also take into account IgorT's experience with adding better (sufficient) heatsinking, your peak may go down, this is until the module warms up, which could take quite a while given good heatsinking. I usually hold the copper part in my hand for a couple of minutes to get the copper warm and I think that this drastically reduce the warm up time needed to reach peak efficiency.


Thanks
brtaman