building my own host...need a wee bit of help

[thestash_16]

hey how u's doin? im good... hope im postin in the right section here... let me know if im not..
Well anyways ive been gathering materials to start putting together my own host. The main things i need a bit of help with is heat sinking. Im planning to order the O-like 50mW green module. You can make it out in the pic below, which i drew in about 5 minutes. I have a steel end cap and plug (used for plumbing) screwed together and inside of that an aliminium cylinder. The plan was to drill a 12mm hole throught the whole piece to press my module into.

That will give me a 30mm x 30mm cylinder for heat sinking.. My question is, will that be a large enough heat sink for 50mW and maybe a 100mW module? I think it would be.

The secound question is what kind of batteries would be best for 50mW? Ive read so many reccomendations for lots of types of batteries and its all confusing to me...

So anything i should know about what type of batteries to use in this situation? Can i just throw the batteries in once ive finished and fire it up? i read that the body of the module is (+) so does this mean i need some sort of insulation over the host itself? The Battery area of my host is going to made from steel tube.

 

[phoenix77]

I think that the diameter of your steel tube will dictate what size batteries to use. Also,since the module is case +, just make sure you put the batteries in with the + end pointing toward the tail-end of your laser, & you won't need to insulate the module. In fact, you'll want as MUCH contact between module & host as possible. You might want to use some Arctic Silver Compound for good contact all around, & with all the metal you're using, I'd think that further heat-sinking is NOT necessary. BTW, you DID post in the correct section for this, YAY rob

 

[laser83]

I'm new to the concept of building myself so I can't help you much. I've toyed around with changing what batteries are accepted in a host though. It's all based on what size the host is I learned. Batteries need insulation and good a connection. That's the reason you can't just use any size you want.

The host size determines what batteries you can use. Next your question was what voltage you need. The amount of volts you are going to need is determined by the output of your laser in this case a 50mW diode is going to require a certain mA setting to get it to run at optimal performance. Ohms law will tell you how many volts you'll need:
Ohmslaw guide From there you would insert the correct batteries.
Lots of tweaking involved to get just right I've heard.

Of course you test everything first on the driver and diode before setting up. You would know the voltage then and what batteries you need.

Note that I have not yet built my own laser I've just started to learn as much as I can because I'm getting ready to. A more experienced member will be able to give you tips and help you out. Hope that helps.

 

[thestash_16]

ive got something to think about now... ive got most of what i need. ill be getting the right sized tube then for the batteries i choose... i know some more things to look out for now so ill read up a bit more on the batteries coz ive got the heat sinking sorted and i seen that you can thow an allen head screw in the sink to keep the module in place.. is there any specific batteries any of you guys would recommend to me to run either the 50mW O-like module or the 50mW module day is selling in his GB? Ie Brand name, cell type, lithium etc...

Thanks for givin me somethin to think about

 

[chipdouglas]

are you going to machine your own parts. or buy parts that are pre made?

 

[thestash_16]

I just asked a superviser if he could get a heat seak machined for me, he said yes, so i gave him the dimensions.. Im getting 20mm on one end machined to thread into 3/4 inch steel pipe..
Im still wondering what batteries to use tho and ive been thinking of using 2AA's any ideas?

 

[charliebruce]

Nope, use Lithium-ion batteries of some sort - much longer "lasing time", since they can store more charge, and higher operating voltages. Just watch out for unprotected batteries, and don't store them at high temperatures. Depends on the size you need, but the best is probably an 18650 for your host.

 

[The_Muffin_Man]

I just asked a superviser if he could get a heat seak machined for me, he said yes, so i gave him the dimensions.. Im getting 20mm on one end machined to thread into 3/4 inch [highlight]steel[/highlight] pipe..
Im still wondering what batteries to use tho and ive been thinking of using 2AA's any ideas?

Steel will insulate it.  Go for aluminum or copper  

 

[thestash_16]

those 18650s are the perfect size... theyre pretty cheap on ebay, you get two for $9 AUD but theyre from hong kong... what will the quality be like? are they worth getting?

 

[Tw15t3r]

For the o-like modules, they are rated 3V, but run on anything from 2.8V to 4V. I heard that with gd heatsinking, run at 3.6V for good output and life at the same time. 4V works well with heatsinking, but the life may not be so long.

 

[thestash_16]

oh rite thanks for the that tip coz these batteries are 3.7V.. im really hoping this project will work out well. if it does ill be posting in the custom lasers section... if not... well i dont know... :