Extra long axles

[billlaws]

I'm building a fairly sizeable kart with a 250cc 6 speed manual bike engine. It will have independent suspension up front and either solid or partly sprung rear end. I want to make this kart wide and low however I'm struggling to find a rear axle wide enough.

I'm after a 30mm axle thats at least 48" long.

The longest I can find at the moment is a 44".

Has anyone ever just bought some precision round steel and used that? Also what did you do about cutting the keyway?

thanks

Will

 

[KieranM]

I have built a machine (not really a kart) but had to hold the same weight. I used silver steel, it was hard as hell to machine but it can withstand alot of weight. You could also get a piece of bright mild steel, machine it and then harden it by bringing it to cherry red and cooling it in oil, not water. The keyways can be cut by a milling machine or a dremel (small hand grinder) with a cutting disk. Make sure you support the axle with various pillow block bearings so as not to be putting strain on one area.

 

[The_Machine]

what type of kart?

 

[billlaws]

sorry should hav said. Its for a fully off road kart.
cheers guys

 

[xoltri]

I bought just a ground and polished stainless steel 1" bar and put in a keyway myself. You can see the details here (with pictures) http://www.diygokarts.com/vb/showpost.php?p=43489&postcount=60

 

[newrider3]

Have you thought about independent suspension in the rear? Junkyard components (CV axles) can be sourced relatively cheaply, depending on your local prices.

 

[gcarter95]

I bought a bar of 1018 steel and had a friend mill the keyway for me.

You should be able to find keyed stock at an industrial supply place that sells driveline components, though.

 

[modelengineer]

I used a piece of 4140 ground high tensile chromoly. That's the stuff you should use for an axle, especially a long one.
I used 1 1/4" diameter which is just a bit more than 30mm.

 

[porsche930dude]

its pretty easy to cut keyways with an angle grinder. Clamp a straight edge on i use bed frame because its hardened steel. I use a thin curf wheel and do one side at a time then cut out the middle and work on the depth.

 

[billlaws]

Have you thought about independent suspension in the rear? Junkyard components (CV axles) can be sourced relatively cheaply, depending on your local prices.

I'm thinking I'm just going to do a simple swing arm arrangement. Probably with the engine on the actual swing arm.

 

[Ferrari motors15]

http://www.princessauto.com/farm/dr...9766-1-x-6-ft-keyed-shaft?keyword=keyed+shaft