This Page is Just About Materials
What Metal to Use, How to Use it.
For your framing you'll want a strong, but light frame.
Our kart project used thinwall sqaure tubing. 1/8" x 1" angle would have done as well. For round tubing, thinwall might be too thin. If you have made a kart from thinwall, let us know.
Most of the store-bought karts use thinner walls and weak materials. The life of the cart surely won't be as long as a quality hand made product.
We like using a mixture of square and round material. If you want pretty bends in the frame on the cheap, review the differences between pipe and tube before deciding which to use.
Why use a mix of tubing?
By using round tubing and square tubing, you will need a chop saw, band saw, or hacksaw, a grinder, and your welder.
If you want to weld round to round, you'll need a tubing notcher or time consuming prepping of the round tubing. This is because welding round to round requires you to "fishmouth" the end of one of the pieces so that it joins solidly to the other (Fig. 1).
However, welding round to square is a cinch because you can just cut the round flat and weld to the flat surface of the square (Fig. 2).
You can also heat the end of round material and pound it flat. This will give you a flat edge to weld to another piece of round (Fig. 3). You will sacrifice looks and strength, so be cautious.
Using angle iron has the benefit that making bends and angled connections is very easy -- you can notch one side, heat, and bend. By adding filler material to the notched area you re-strengthen the frame. Even if you don't make the whole frame with angle iron, you can still use it for pieces that need to be bent at angle.
If you want to jazz up your frame with bends, we suggest using pipe and getting a Harbor Freight pipe bender. Note that it only bends pipe, not tube. [What's the difference?]
Since it's more difficult to bend square tubing and fishmouthing round is difficult, many people use a mixture of square and round.
Cutting Your Materials
You'll need a chop saw, grinder with cut off wheel, or a hacksaw to cut your materials. Circle saws will often accept an abrasive blade as well. If you're using a hack saw, buy a new blade. Your old one is surely dull.
A chop saw is the best since you can get nice straight cuts. If you don't have one, you don't need an expensive one, so keep that in mind. A handy way to ensure you get two pieces of tubing exactly the same length is to use vise-grips to keep two pieces together (Fig. 4). It saves time, too!
Before you start welding, make all your cuts first. Then lay out the frame completely to get an idea of what the finished product will look like.
At this point you'll know if something isn't working, and can fix it before it eats up time later. And if you're getting a someone else to do the welding for you then they will greatly appreciate that everything is ready to go.