why won't my mag mod work?

[at4rxj]

I'm at my wit's end... can't figure this out.

3D Mag
3 x tenergy 10000mah nimh d cells
regular switch
direct drive to a P7
heatsink, P7, and metal reflector from BrightLumens

I put it all together and it doesn't work. I've tried figuring out why...

I'm only getting .2v at the leads

I tested continuity - good at tailcap from neg lead, good to positive spring on switch from lead

switch seems to function fine with continuity test
everything seems to be working well until I put batteries in

Battery voltage checks out ok, even tried a set of regular ones

I just don't know what else to look at... Please help.... :mecry:

 

[tx101]

I dont have any Tenergy D cells but are the positive ends of the battery
flat ???
Could be the battery is not making contact with the positive spring in the Mag because the spring sits in a concave

Had a similar problem with a flat top Li-ion D cell. You can either use a magnetic spacer or flatten the plastic on the Mag switch at the battery contact end (search for threads by Wquiles, he uses a lathe) with a file

 

[Benson]

Is the heatsink shorting the LED? The slug on P7s is +, and the flashlight body is usually -...

 

[Benson]

I dont have any Tenergy D cells but are the positive ends of the battery
flat ???
Could be the battery is not making contact with the positive spring in the Mag because the spring sits in a concave

Had a similar problem with a flat top Li-ion D cell. You can either use a magnetic spacer or flatten the plastic on the Mag switch at the battery contact end (search for threads by Wquiles, he uses a lathe) with a file

I have some Tenergys; they're regular button-tops.

 

[ledaholic]

Is the heatsink shorting the LED? The slug on P7s is +, and the flashlight body is usually -...

+1

 

[AlexGT]

Did you check the polarity of the led? are your wires backwards?

AlexGT

In the pics the little wires point towards the "+" and the lonely wire in the other side is the "-"

 

[at4rxj]

Tenergy's are regular button tops and should be contacting the spring fine.

I put thermal adhesive between the P7 and the heat sink. In addition, the heat sink is anodized. I don't think it's shorting. Either way, though, I but the wires going to it from the switch and I'm testing the bare leads. The LED is separate and works fine as it's installed on the heat sink with another power source.

Basically, I just have wires coming out of the switch right now and I'm not getting voltage at them.

 

[Mirage_Man]

Tenergy's are regular button tops and should be contacting the spring fine.

I put thermal adhesive between the P7 and the heat sink. In addition, the heat sink is anodized. I don't think it's shorting. Either way, though, I but the wires going to it from the switch and I'm testing the bare leads. The LED is separate and works fine as it's installed on the heat sink with another power source.

Basically, I just have wires coming out of the switch right now and I'm not getting voltage at them.

Maybe it's the switch?

 

[at4rxj]

Maybe it's the switch?

That was my first thought, but testing continuity of the positive works fine... goes through in on position, and doesn't in off position.

 

[Mirage_Man]

That was my first thought, but testing continuity of the positive works fine... goes through in on position, and doesn't in off position.

Your making good contact with the set screw to the body through the ano?

 

[at4rxj]

Your making good contact with the set screw to the body through the ano?

Yes

neg lead shows continuity all the way to tailcap

 

[ledaholic]

Remove the head so you can get to the top side of the switch. Install the batteries, put negative lead of meter on the body (bare metal), put positive lead of meter on the top side of the switch and cycle the switch on-off. If you don't get any power, either the switch is not working or batteries are not making contact. Did you take apart the switch? If you did, do it again and double check assembly. You might also try regular alkaline batts. What is your negative wire attached to?

 

[Alan B]

You've started already, but break it down into sections and prove each section works. EG check for voltage from battery minus to switch output. Check for continuity from spring to tailcap. Is the tailcap when on fully tightened against the body tube? The anodized threads won't carry current.