First laser build problems

Hello, I have been reading and learning here for a while now, but have just undertaken my first laser build. Everything went well at first. I got the leads from the diode (9mm 445nm from DTR) soldered to the driver, (2.3A from survival laser) assembled the host (also from survival laser), and charged the batteries.

The first time I pressed the power button, everything worked great. The laser fired up, I was able to focus it and seemed to have no problems. However, when I was assembling it I noticed that I had left the leads too long and so it was a VERY tight fit.

I decided disassemble everything, cut the leads and re-soldered everything. one that was done and re-assembled, I put the batteries back in, pressed the power button, and the laser turned on for a split second and then nothing. I have inspected all of the connections, pins, ground, batteries, and button, but cannot find anything wrong.

My question is, WHAT DID I DO WRONG? Did I short out the diode, when I cut the wires or something. I am really bummed right now and don't want to have to but another diode. Help me out please!!

Here are a couple of pictures of the build as I was working on it the first time.

Can you take a picture of the connections on the driver and diode?

upaa27 said:

Can you take a picture of the connections on the driver and diode?

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These are the best I can get. The Diode came from DTR with the leads soldered on. The driver is mounted in the brass ring and soldered to the pill, so I can't get pics of the connections to the driver. The driver came with the leads soldered to it as well.

Have you tried bypassing the tailcap switch with a bit of wire? if its not that it could be your batteries. You might have damaged the diode if you didn't short the driver before putting it together ... hopefully its not a damaged diode.

3Pig said:

Have you tried bypassing the tailcap switch with a bit of wire? if its not that it could be your batteries. You might have damaged the diode if you didn't short the driver before putting it together ... hopefully its not a damaged diode.

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The switch is not the problem, I have already gone through all of the steps to check it. Unfortunately, I think I damaged either the driver, or worse, the diode. I guess this time I will have to order the diode with the driver already attached from DTR and hope for the best.

if you did not short your driver after you disconnected the diode, your diode is more than likely toast.
it's one of those little things that can cost a lot of money. The driver holds a charge even after you disconnect the diode, so when you reattach it, the charge in the driver blows out the diode. You have to touch to positive and negative driver leads together to take away the charge before connecting a diode.

bdgreenb said:

if you did not short your driver after you disconnected the diode, your diode is more than likely toast.
it's one of those little things that can cost a lot of money. The driver holds a charge even after you disconnect the diode, so when you reattach it, the charge in the driver blows out the diode. You have to touch to positive and negative driver leads together to take away the charge before connecting a diode.

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It looks like this is exactly what happened. I did not even think about shorting the driver before re-attaching it to the diode. I have already ordered a new diode from DTR. I guess I can check this lesson off. It has been learned, never to be forgotten again.

Well i learnt something from this too! i have desoldered my diode twice from my M140 c6 build but luckily i havent blown a diode myself, maybe because mine uses a boost driver
Is the shorting thing something that is more needed with a buck driver ? boost driver? or both?

I wouldn't just assume it was a charged output cap. I've disconnected the diode from driver like that on several builds and haven't had this happen. I didn't even think the output cap could charge up like that while still attached to the diode, then fry said diode upon reconnect. Except it didn't kill it immediately, it powered up then died.

I would double check the driver inside the pill. I've read about shorting issues with those drivers. If it is the driver I'm thinking of, it should have had a dab of epoxy on the problem area. Even if it did have that, it still would be a good idea to check.

I had something similar happen, and it was a driver issue.

ChaosLord said:

I wouldn't just assume it was a charged output cap. I've disconnected the diode from driver like that on several builds and haven't had this happen. I didn't even think the output cap could charge up like that while still attached to the diode, then fry said diode upon reconnect. Except it didn't kill it immediately, it powered up then died.

I would double check the driver inside the pill. I've read about shorting issues with those drivers. If it is the driver I'm thinking of, it should have had a dab of epoxy on the problem area. Even if it did have that, it still would be a good idea to check.

I had something similar happen, and it was a driver issue.

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I checked the driver and it was operating properly. The only thing that would not work was the diode. I went ahead and ordered a new diode from DTR's Laser Shop. This time I went ahead and ordered it with the 2.4A X-Drive driver already attached. I figure this will keep this headache from happening again.

Yeah, just wanted to make sure you checked the driver. Really sucks to blow a diode.
At least when you get your new module, it'll be ready to go!

lpsouth1978 said:

I checked the driver and it was operating properly. The only thing that would not work was the diode. I went ahead and ordered a new diode from DTR's Laser Shop. This time I went ahead and ordered it with the 2.4A X-Drive driver already attached. I figure this will keep this headache from happening again.

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Don't forget you will also need the drilled pill and a battery contact board from Survival Laser to go with that module from DTR.

Alan

Pi R Squared said:

Don't forget you will also need the drilled pill and a battery contact board from Survival Laser to go with that module from DTR.

Alan

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Thank you. I actually ordered those yesterday as well.

I got the new diode with driver from DTR's today. I cannot fully express how impressed I am with the level of service Jordan provides.

Now I am just waiting for the new pill and battery board to arrive. They shipped today, so I expect to see them by Wed.

A couple of other things I ordered last week for this build were Arctic Silver thermal grease, 4x Nitecore 18650 3100mah batteries, and a Nitecore D4 battery charger. This build has quickly become a more expensive project that I had planned on, but at least I will be able to say that I had something to do with the build (even if it was only a small part), and I know what quality all of the parts used in it are. I couldn't say the same thing if I just purchased a laser on line.

Got the battery board and pill today, put everything together and the laser is now alive. It definitely has a lot more power than my roommates 2W 445 laser. It burns EVERYTHING much faster than his. The only issue I have now is the duty cycle. I knew that it might be a short duty cycle with this host and heatsink, but now I know just how short. It looks like I will have to keep it at no more than about 20 sec on 60 sec off. It heats up VERY fast.

I LOVE that I can have a long laser with 2x 18650 batteries, or a short laser with 2x 18350 batteries. It seems like to only noticeable difference is the length of time you can use the laser before replacing the batteries.

I take it back, I already have another problem. The divergence is suddenly all over the place. It started out very normal, but now I cannot focus the beam well and it is a weird shape. Here are a couple of pics. What happened and is there anything I can do to fix it?