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Trouble setting flexdrive.






What is your power source? Also at 1.5A with no heatsink on the driver it will heat up fast and drop in output.
 
Looks like the blob might be shorting the via at the top edge in your pic.

What are you using as a load?

I don't see any heat-sinking ... this is a must for 1.5A, if its not a short it may be going in and out of thermal shutdown.
 
Make sure your bridging blob isnt touching the square in the picture. I dont have one handy to look at so I'm not sure what that pad is connected to. Better safe then sorry. Also your positive input for the battery looks pretty close to the resistors too. I would double check that its not actually touching.
 
It looks like the range is set fine. The pot is really sensitive. It jumps from 1.1A to 1.5A and back to starting over in an instant. Also I like to strip my wire so that just enough is coming through the hole that it is visible from the top. You can barely hang your fingernail on the wire that is sticking out of the hole. And some flux on the wire will do all the work of getting the solder into the hole;)
 
Is it possible that i just got a weak flexdrive? I have been fiddling with it, turning the pot very slowly and it always goes from 1.1A down to 600mA I have a few more coming in the next couple of days, maybe ill just wait for those and use this for a oneish watt build. I know flexdrives can vary from one to the other, I'm just curious if they can vary by this much.
 
drlava said:
Hi, you should measure the internal resistance of the battery you are using:
http://laserpointerforums.com/f67/h...es-how-measure-internal-resistance-57576.html
It needs to be 'excellent'. But if I were you I'd only set it for at most 1.1A because you don't gain much more visible brightness with the extra 400mA.
Click to expand...

I was going to try your testing method before but the only batteries i have are 1 week old AW batteries from lighthound that haven't even been used prior to me setting the flexdrive. So i was just assuming they would be excellent.
 
I do have to chime in and say that between my two 445 builds, one at 1A, the second at 1.5A that there is considerable difference between beam brightness and color. The one at 1.5A is much more blue than the one at 1A. So much so even to a non-laserist the 1A looks purplish to them.
 
the color of the beam (and thus the apparent brightness) is mostly affected by the diode itself and not the current (1A vs 1.5A). Another factor that can affect the color is letting the diode get hot. But all you need for that is poor heatsinking. CD, if you set both to the same current, the one that is brighter right now I'll bet will still look brighter.
 
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I am still having the same problems, i set 2 more flexdrives today (trying to get them to 1.5A) and i still can only get them to 1.1A before they drop back down to ~600mA. This time my soldering was much cleaner and there was definately no solder or wires touching something they shouldnt be. I spend about 20minutes trying to set one with no luck. Im turning the pot extremely slowly but i still have not seen a number higher than 1.1A on my DMM. This is how i bridge the connections.

2wf7578.png


I put a blob of solder down connecting the 3 on the left. then i make a line from that to connect the other 2. Is there something really stupid i am doing? Or am i going to be stuck making builds with flexdrives maxed at 1.1A

Thanks again!
 
Hi, I just ordered the V5 too. The instructions that came with mine say to remove the last resistor on the bottom right for 1.5A output. The new pdf manual is different from the old one. I looked online but couldn't find one that says to do this like mine does.

I'm not sure how to post it here but if you email me I'll send you a copy of the pdf file.
 
Sorry to go a little off topic here, but this thread seems the perfect opportunity to ask about a problem I had trying to set my first flexdrive.

I'd love to know how you manage to solder these connections together as I've already killed one flexdrive I'd recently ordered and had to order a replacement.

No matter how hard I tried, I couldn't get the solder blob to stick where I wanted and eventually it all got so hot the actual resistors desoldered and moved out of their position!!

It's turned into a nice little desoldering and smd re-soldering project for the future ;)

532_1839.jpg
 
Did you tried on a dummy pcb ? Like old computer stuff. Good for practice solderings.
You need to heat the tin just enough to become liquid and apply it to the connections. Too hot and the tin becomes too liquid. You can cool the flexdrive before starting the job.
 
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