Weld the Axle Stubs to the Tubing

The process to weld the axle stubs (bolts) to the fixed axle is very important because this will be a load bearing portion of the kart. Here are the steps:

1. Grind a slight bevel on the edges of the tubing ends for maximum weld penetration. I did not do this as my welder was strong enough to weld through, but this should be done if you are using a light duty welder.
2. Tack weld the bolts to the tubing in four opposite corners.
3. Use a straight edge or level to check that the bolt runs parallel with the tubing on all four edges. Use a hammer and tap the bolt into place.
4. Tack between the four tacks for a total of 8 tacks.
5. Verify the axle bolts run parallel to the tubing.
6. Weld one side of the bolt to tubing junction at a time. Once you have the first side welded, flip the axle over and weld the opposite side to minimize warping.
7. If you have a small welder, clean the welds with a wire wheel attachment on your angle grinder, and perform multiple weld passes over the edges of the first weld for added strength. My welder was beefy enough to just do one pass.
8. Repeat on the other end of the axle.

Go Kart Rear Fixed Axle Welding

Because the drive wheel and passenger wheel connect at different spots, you will need to offset the fixed axle from the head of the bolt to the go kart frame. Doing this will allow the rear wheels to be the same distance from the frame.  The steps are as follows:

1. Orient the 6″ bolt end of the axle on the drivers side of the frame.
2. Per the plans, measure the correct distance from the back of the kart to the fixed axle. Double check the rear axle distance from the front of the axle, (they should be the same on both sides).
3. Measure 1 1/2″ from the driver’s side bolt head to the frame and 2 11/16″ from the passenger bolt head to the frame.
4. Tack weld the axle frame.
5. Weld the axle to the frame.