qwertyydude
Flashlight Enthusiast
- Joined
- Aug 10, 2008
- Messages
- 1,115
Ok I got the Tank TK-703 AAA light from DX and had experience with the switch not being reliable. After much experimentation since I bought extra switches, good idea if you order this light. But I found the switch has three points of contact to complete the circuit.
1) The battery negative contact and spring.
2) The spring and cup.
3) The actual switch contact between the cup and ground plate.
To minimize the number of points of contact I simply soldered the spring end into the cup, just solder a blob to the end of the spring and then put a small amount of flux on the blob and set the spring in the cup and heat the cup til the spring solders itself into the cup. Then solder the spring and cup assembly onto the battery negative contact. This is tricky since it's on a plastic part. So to do this just bend the tab up and carefully solder the spring end to it and bend it back down. To do this just dab some flux on the spring and contact, put a blob of solder on your iron, and while holding them together touch the blob of solder onto the joint and the solder should instantly wick between the spring and contact. This should leave the only point of contact in the switch between the cup and ground. I've found this to make the switch 100% reliable.
Before:
After:
1) The battery negative contact and spring.
2) The spring and cup.
3) The actual switch contact between the cup and ground plate.
To minimize the number of points of contact I simply soldered the spring end into the cup, just solder a blob to the end of the spring and then put a small amount of flux on the blob and set the spring in the cup and heat the cup til the spring solders itself into the cup. Then solder the spring and cup assembly onto the battery negative contact. This is tricky since it's on a plastic part. So to do this just bend the tab up and carefully solder the spring end to it and bend it back down. To do this just dab some flux on the spring and contact, put a blob of solder on your iron, and while holding them together touch the blob of solder onto the joint and the solder should instantly wick between the spring and contact. This should leave the only point of contact in the switch between the cup and ground. I've found this to make the switch 100% reliable.
Before:
After:
Last edited:
