DIY Aluminum Bus Bar

Busbars make connecting batteries more efficient.

If you are fed up with too many wires running between batteries in your electrical circuits, then a bus bar (or "busbar") could be the solution. Busbars are pieces of conductive metal that are used to let a charge run between two points. Because metals like aluminum are already conductive, when you attach these metals to two batteries the metal gains a charge as it runs between batteries. To control this charge you just need to add contact connectors and wire connectors to an aluminum bar.

Things You'll Need

• 1 foot aluminum bar (1/4 inch thickness)
• Permanent marker
• Protective eye wear
• Dust mask
• Drill
• Pilot bit
• Final bit
• Chop saw with abrasive blade
• Vice grip
• Dremel brush
• 4 3/8 inch bolts
• 2 3/8 inch nuts
• 2 3/8 inch washers
• 3/8 inch wrench

Instructions

Preparing the Bar

1. Put on your protective eye wear and dust mask.

2. Measure the distance between the points that you are connecting with the busbar. Add 2 inches to this measurement and write it down.

3. Start from one end of your aluminum bar and measure out the length between your points. Mark this length with an X and draw a vertical line through the middle of it.

4. Measure 1 1/2 inch from each end of your bar. Mark these points on the bar with an X.

5. Mark another X 3 inches from each of your already marked points. There should now be 4 marks on your bar, two of which are 1 1/2 inches from the ends and two others that are 3 inches from each other and from the marks near the edges.

6. Drill into the middle of each X with your pilot bit.

7. Expand your holes with the 3/8 inch drill bit. After this drilling you should not be able to see any of the hole markers you had drawn.

8. Put your bar in the vice grip and saw off the end of the bar beyond your measurement line.

9. Run your dremel brush over your bar to dress it.

Completing the Bar

1. Put your bolts through the two middle holes in your bar.

2. Screw the nuts over these bolts using your wrench.

3. Flip your bar so that the bolt heads are facing downwards (and the threaded sides are upwards).

4. Place the two empty holes over the positive contact of one battery and the negative contact of another.

5. Set your washers over the empty holes and place your bolts into these holes and use your hand to screw them in tightly.

Tips & Warnings

• Your pilot bit should be about three times smaller than your final bit (which must be the same size as your bolts).

• The ratio of distance between the last hole on each end of your bar and the ends of your bar, and the distance between the holes in the middle of your bar is about 1:2. So, if the distance between an edge hole and the edge is 1 1/2 inches, the distance between holes in the middle of your bar should be 3 inches.

• Draw a straight line through the middle of all of your hole X markings. If the line is straight, then all of your holes will be lined up when drilled.

• You can screw the bolts on the end of your bar into recessed battery contacts. However, if you are using batteries with exposed contacts, then use nuts to hold the bolts at the end of your bar in place while it connects your batteries.

• The shrapnel and dust that is created from drilling and sawing through metal can be dangerous. Along with wearing protective gear, clean up this shrapnel and dust once you are done drilling and sawing.

• Do not saw any excess length off of your busbar before you have finished drilling. You can use this extra length to hold you bar down as you are drilling.

References

• The Physics Hypertextbook; Electric Resistance; Glenn Elert; 2011
• YouTube; How to Make Mini Buss Bars