what type of tube should I use

[speedy_moe]

I am going to build my kart from scratch in the next month or so. I would like to get some input from everyone here. I am going to use square tube just because its easyer to weld.

Now for the help, what diameter should I use and how thick of walls should I get.



Some back ground on how the kart is going to be used. I am going to do a little street driving and a little uneven grassy area driving. The uneven area is going to be on a farm that my family owns.

Please help..............................

 

[ironman]

1 1/2 inch by 1 1/2 inch box tubing will work great

 

[jr dragster T]

Thats what i used with a .125 wall its sooooo strong!

 

[ironman]

i know great size i think. thats what im going to use on all karts i build.

 

[wingnut]

Almost all the go-cart plans I've come across that use square tube call for 1 inch square with .125 wall. Your local steel shop would refer to this as 'thick wall' tubing. 1 1/2 inch would certainly be stronger but much heavier which would make your cart slower. Seems like overkill to me for running on mostly level ground.

 

[ironman]

very true i just reallt like 1 1/2 box tubing gives plenty of room when you are doing bolt ons. i wounder on a normal size cart how much would be the weight different.

 

[wingnut]

I guess that depends on what you call 'normal'. Most of the plans I've seen for simple ladder frame carts intended for kids come in at around 20ft of tubing. Using the numbers from this web site: http://www.jimssupply.com/square rec_tubing.htm . That comes out to about 45lbs for 1.5 inch and 30lbs for 1 inch. 15lb might not seem like allot but it's half the weight of that 6.5 hp harbor freight motor. Naturally we're talking about much more weight if you're building a roll cage or a cart for an adult.

 

[jr dragster T]

I tested a peice of 1" wide by 125 its just flexes like rubber

 

[ironman]

I guess that depends on what you call 'normal'. Most of the plans I've seen for simple ladder frame carts intended for kids come in at around 20ft of tubing. Using the numbers from this web site: http://www.jimssupply.com/square rec_tubing.htm . That comes out to about 45lbs for 1.5 inch and 30lbs for 1 inch. 15lb might not seem like allot but it's half the weight of that 6.5 hp harbor freight motor. Naturally we're talking about much more weight if you're building a roll cage or a cart for an adult.

i guess i better go on a diet because ill be useing 1 1/2 on my karts.but thanks for the info its always good to know these little things.helps everybody out

 

[speedy_moe]

But using 1" square tube with .125 thick wall with a little more cross bars to even out the weight would seem like it could hold just as much as the 1 1/2" square tube. Please let me know if I am thinking right on that.

 

[jr dragster T]

Im afraid not. 1 Inch wide is just too flexy for any weight of driver. Its just not safe.

 

[ironman]

But using 1" square tube with .125 thick wall with a little more cross bars to even out the weight would seem like it could hold just as much as the 1 1/2" square tube. Please let me know if I am thinking right on that.

i just like to be safe when it come to my kids for me if i can go fast i might use thinner but i just like the size and i know its going to be strong and for me it seems easier to attach different parts to the kart frame.

 

[speedy_moe]

OK so the best size would be the 1.25 square tube. Now what is a good thickness that would be good for off-roading, just some light off-roading on a farm.

 

[wingnut]

Maybe I'm missing something. Is one inch square tube less rigid than one inch round? The Panther from DesertKarts and the DirtDevil from diyden are two prolific designs that both use one inch round. SAE International is one of the most safety oriented organizations in the business and they allow one inch tubing. I'm new to this hobby myself but the only design that I've come across on the internet that calls for more than one inch tubing is the ST2 variants from BadlandBuggies and it only calls for 1 1/4....

 

[speedy_moe]

I agree but it also depends on the thickness of the walls. That is the question that I am asking. If I used 1" square tube what thickness of walls should I use and if I went with the 1.25" square tube what wall thickness should I use?

 

[jr dragster T]

We told you 1 1/2 by 120-125 wall. Forget about the 1 inch stuff its no good for chasis building!

 

[ironman]

i can only tell you what i have used on the cart i have .but i also have a kart with round tubeing and it has a few bends in it where it has hit things 1 inch,so i went with 1 1/2 for my son other cart when i build mine i will be building a speed demon so i will see how the 1 1/2 does and go from there.

 

[speedy_moe]

i can only tell you what i have used on the cart i have .but i also have a kart with round tubeing and it has a few bends in it where it has hit things 1 inch,so i went with 1 1/2 for my son other cart when i build mine i will be building a speed demon so i will see how the 1 1/2 does and go from there.

Ironman, have you built the demon:devil2? How is the instruction for it? Is it easy and how long did it take you to build? I am wanting to build one but not sure how long it will take and if the instructions are really as good as they say.

 

[ironman]

this is my own build not nothing you would buy from the store look under projects at mini cart and you will see the frame i have built so far.took about 20 feet of box tuing

 

[wingnut]

I'd use one inch thick wall (.125) tubing especially if you're going to build anything more than a flat ladder frame. Have you looked at the plans for the Dirt Devil? It's only $28 from diyden.net. That would take all the guesswork out of it. If you wanted to explore your own design, the dirt devil plans would still serve as a good guide.