Thread: hollow axles legal???

Have a look here and here... should answer as many questions as it poses.

Is solid bar really any stronger than thickwall hollow tubing in this situation?

My water cart(not the road...)has been bouncing around for two seasons using hollow tube/welded stubs which is solid mounted(ie no suspension). Its still straight as the day I made it even though its carrying 1Ton+ every load!

Dose the fear of saying yes to anything have everyone scared.

There is nothing to say they are not legal in the regulations.

You can purchase weld in stubs at any trailer supply place.

I have owned/built several trailers with heavy wall hollow axles and never had a problem.

Fillet weld around the end of the tube and 2 plug welds about 25mm from the inside end of the stub, if the weld breaks/cracks then the stub can't come out of the tube.

Repaired a dual hollow axle car trailer recently that had the front shackle fall off the frame at speed and ended up wraping the front axle in behind the rear axle, it all stayed together, badly bent but nothing seperated.

If you follow all the regulations and have no idea of how to weld or what materials to use and your trailer falls apart and hurts someone, then you will be liable!

Originally Posted by Harry72

Is solid bar really any stronger than thickwall hollow tubing in this situation?

As far as bending goes, solid rod and tube with a reasonable wall thickness are similar. In other words, if the tube works then replacing it with a solid rod won't achieve much.

Shear strength is a different matter, solid win hands down there.

This got me curious so I've just spent the last 45 minutes searching NSW licensing, the ADR's and vehicle standards.
Suprisingly there is no standard that I can find on this.

If this is a trailer you're going to license, call the place you're taking it for inspection and see what they will pass. If it's repairing a licensed trailer go with common sense.

Personally, I would not bother with hollow. You're looking at around $30 for a pair of stubbs which you'd need to get welded on to the axle (and for a job like that you want it done right) where as a 39mm beam axle will set you back $47 for 47 inch up to $66 for 80 inch - these are Qld (Active Fabrications) prices but I guess NSW would be similiar.
Cheers

Originally Posted by matt9422

Hello, i was wondering if hollow axles are legal in nsw... ?

Cheers Matt.

Put simply, Yes.

Why would you bother though?
Depending on size you're looking at $32 a pair (minimum) for 39mm stub axles plus the tube and welding - an 80 inch solid 39mm axle will only cost $66.

For such a little saving you might as well go the solid axle.

Legal does not mean smart, the regs say a trailer is legal with one safety chain but I would never own a trailer that doesn't have two.

Originally Posted by smidsy

Why would you bother though?
Depending on size you're looking at $32 a pair (minimum) for 39mm stub axles plus the tube and welding - an 80 inch solid 39mm axle will only cost $66.

For such a little saving you might as well go the solid axle.

Legal does not mean smart, the regs say a trailer is legal with one safety chain but I would never own a trailer that doesn't have two.

For smaller stuff, I agree. If your making an axle yourself, the only real advantage is the infinite adjustability of your axle length before you weld it. Otherwise, there's no discernible difference between hollow and solid, cost wise, rated capacity or weight.

It's when you get into the higher rated axles that there can be a significant weight saving by having a hollow axle. But... this is not something I'd recommend for the average backyard workshop.

I do not believe there is, nor can there be any reason that a hollow axle can be made illegal in principle.

Because there are a great many vehicles that have in effect hollow axles in some form.
Large semi trailers for instance do not have solid axles, nor do most pasenger cars.

But the practicality is being able to guarantee that a given axle performs to the specification required.

There is a both implied and specificaly stated obligation to keep track of the origin of functional trailer parts you use and be able to justify how they are rated for strength and function.

If you buy a complete axle, you can point to it and say, I baught it from so and so and they published this rating for it, I have used it in accordance to their publised data.

If you have access to engineering support you could very easily fabricate an axle with a hollow centre tube, and point to the engineering documents and say this is how the rating was derived.

But for most of us we have no ability to justify and document such an axle.

So when you fill in the " self assessment for light trailers" form, that you will sign at the bottom, assuming responsibility for the life of the trailer, where do you get the figure for "load rating of axle".

There are a great many things that are very reasonable to make and or fabricate for a trailer as a private individual.
But there are three things it is wise to buy from a reputable and tracable source, the axle, the springs(or suspension) and the coupling.

cheers