DIY build questions

[jordan6194]

hey all im new to the forum so hopefully this post doesnt infuriate too much. im undertaking my first high powered build (having previously made a 5mW laser) and im worried about sourcing parts online.

1)
this is the diode i am considering:
1W Blue Laser Diode to 18 5 6mm 445nm | eBay
for the supposed power output is this likely a legit buy?

2)
also the housing i am considering:
To 18 5 6mm Laser Diode LD Copper Housing Mounts with Focusing Lens | eBay
here i am worried about the lens, the seller does not specify the material but ive read elsewhere on the forum that acrylic cannot handle higher power lasers so would i be better off sourcing a glass lens housing?

3)
i plan to drive the circuit using an LM317T regulator however the diode requires 1A of current, meaning the driver needs to use a resistance of 1.25. i was considering using a combination of fixed resistors and a pot but im worried about how small the resistance needed is. any recommendations for a better driver circuit (preferably DIY)
i understand this forum is very much about learning rather than being given the answers so even directions to other threads would be appreciated.

thanks for any help anyone can give! :thanks:

 

[Pi R Squared]

1) no don't buy that, it's used although it seems like a fair price I recommend you don't buy used diodes. Buy from DTR: https://sites.google.com/site/dtrlpf/ he also sells on eBay and sells some items on Amazon.

2) absolutely do not buy that! It is non standard and ships from Hong Kong. Try to use standard size parts that most of us use that are interchangeable and easily replaced. And try not to buy stuff from HK and China unless you get a really great deal. You can buy modules and lenses from DTR, and Survival Laser International Home and from http://www.aixiz.com you can even buy a diode already pressed in a module with a lens and leads attached.

3) that could work but is best for lower power lasers but can work, they are best with the voltage only as high as they need or it will heat up. I assume you are going to build this in some kind of project box and not one of the usual hand held hosts?

You can easily just buy a suitable driver. Don't make it too DIY for your first build or something will go wrong.

Alan

 

[jordan6194]

thanks for the quick reply! okay i shall stay away from used diodes and those that look like cheap china knockoffs etc

I like the look of DTR's stock and after looking through his threads i think this will be a more suitable diode
https://sites.google.com/site/dtrlpf/home/diodes/oclaro-700mw-638nm-diodes
using his copper mounting aswell.

for the sake of customs i am thinking of shipping the driver seperate, using one of DTR's driver links
FlexMod P3 Laser Driver
however they are out of stock at the moment so that will depend on restock time

a 700mW laser is obviously a lot more powerful than the little 5mW i already have so will the mount be sufficient for say 5mins continuous operation or will additional heatsinking be needed? eg:
Laser Heatsink for Standard Aixiz or Copper Diode Module US Seller Fast SHIP | eBay

i also have a 12v fan planning to be mounted mainly for the driver cooling

Thanks,
Jordan

 

[Pi R Squared]

No you can't run it for 5 minutes, I wouldn't go more than 30 seconds with that thing. You need something 10 times bigger with a fan blowing directly on it if you want 5 minutes.

If you are going to set your own driver then you have to have a test load and a DMM and know how to properly use them. You can buy a driver that's preset to what you need (between 900mA and 1.2A). This guy is ok to buy drivers from: http://laserpointerforums.com/f39/x-drive-x-boost-88589.html

Alan

 

[The Lightning Stalker]

It seems like you are wanting to build a
labby, correct? To get 5 minutes of
runtime, you will need a large copper or
aluminum heatsink. There are machinists
here who can make you something like that.
I would do it for you, but I am busy with
other things at the moment.

I recommend buying a module W/driver and
leads from DTR. It will save you from some
of the beginner woes and allow you to see
what it looks like when it's done right.

Then get a pair of safety glasses from
Survival Laser or AixiZ to protect your
eyesight.

 

[jordan6194]

sorry i wasnt really thinking when i said 5minutes, which is actually a fairly long time :crackup: 30seconds should do just fine but i will also position a fan onto it for extra cooling.

i have been looking into a test load from this thread
http://laserpointerforums.com/f39/fs-selectable-test-load-up-3a-assembled-diy-kit-stock-63450.html
i managed to acquire all the components from a local parts store but the diodes are too thick to fit into the stripboard :crackup: im hoping to get the PCB from jufran when he replies to my PM

your driver link may have made that irrelevant anyway as i think the x-drive v7 mini 1.0A would do the job well

Jordan

 

[jordan6194]

It seems like you are wanting to build a
labby, correct? To get 5 minutes of
runtime, you will need a large copper or
aluminum heatsink. There are machinists
here who can make you something like that.
I would do it for you, but I am busy with
other things at the moment.

I recommend buying a module W/driver and
leads from DTR. It will save you from some
of the beginner woes and allow you to see
what it looks like when it's done right.

Then get a pair of safety glasses from
Survival Laser or AixiZ to protect your
eyesight.

woops didnt see your reply there sorry! like i said, i wasnt really thinking when i said 5mins. would a 30sec runtime still need a heatsink?
yes DTR is looking like my savior at the moment!

 

[The Lightning Stalker]

woops didnt see your reply there sorry! like i said, i wasnt really thinking when i said 5mins. would a 30sec runtime still need a heatsink?
yes DTR is looking like my savior at the moment!

Yes. These diodes get hot quickly without
a heatsink. There are plenty of 12mm
heatsinks around that will do 30 seconds
easily. Time gets away from us easily when
lasering, so try and stay attentive.

Don't forget the safety glasses.

 

[jordan6194]

thats great, thankyou stalker ive ordered the parts now for the painful 2-3week wait! yes glasses are also on the way too of course

thankyou for the suggestions Alan hopefully it all goes well :yh: