Wednesday, October 10, 2018

Hat-tip mgumbua: Another tip from comments

The post on a common, automotive battery. The first few threads often get balled up when too short of a threaded fastener is used.

A common 3/8" bolt, flat washer and nut. It is important that much of the length of the bolt be threaded. A carriage bolt can be used for this application.
The cable is not shown for clarity. The nut is screwed as far up the bolt as it will go. Then the washer is pushed up next to the nut. The bolt is pushed through the cable end and is hand turned until it bottoms out in the threaded hole in the battery post. It is not possible to get more thread engagement by any other method.

Then the nut is turned to compress the cable end to the exposed face of the battery post. Let me rephrase: The bolt is not turned, the nut is turned. Do not over torque! Remember, stripping out the first few threads is what got you into this problem. A split lock washer is optional, perhaps even advisable.


  1. That is always the method I use.

    Since it sticks out farther, it can short to the body. Which can be bad, because your battery can put out HUGE current in a direct short.

  2. The extra bolt sticking out i very useful when you need to jump the vehicle as it gives you amuch better attachment for the cables!!

  3. is very useful and a much better

  4. Yep, oldie but a goody! And works like a champ, 'except' for that shorting thing... sigh... Don't ask me how I know... sigh