Thread: heat treating stock axles

Originally Posted by isuzurover

Hey Slunnie I think you are onto something!!! Cheap Gun-drilled axles! Now where did I put that curtain rod...

I've got a special lamp drill for the lathe that should do the trick. Can give it a flame tempering with the propane too for some heat treatment.

Originally Posted by Slunnie

Quite seriously, I think that you'll find the factory axles are made from low carbon steel.

Apparently thats the cheapest stuff that Bunnings in the UK stock

apart from Curtain rods.

B & Q Slunnie we don't have joints as classy as Bunnings

For those interested in history, it is interesting to note that Land Rover was initially planning to use these for axles:



After WW2, steel was in short supply, and the French were feeling grateful that the english saved their arses...

However, during testing of the pre-production vehicles, it was found that they absorbed too much oil, meaning that the hub seals never leaked. So, in order to preserve the designed-in rustproofing system, and ensure steady sales of hub seals, they moved on to plan B:



However, due to complaints about axles breaking (or the local ploughman stealing them for his lunch), Land Rover finally switched to using steel when B&Q opened its doors - as mentioned above.

This coincides with the appearance of the +35 on late SIIAs. This is because the steel Land Rover were using was 35% stronger than the cheese sticks.



Hope you all enjoyed the history lesson.

I still think the cheese stick axles would have been more effective than that steel one!

thanks for the replys. A heat treatment expert would be handy, I did study metalurgy at rmit but it was a while ago now. From memory a large crystaline structure makes a harder steel, to get this you quench the steel from hot to cold fairly quickly. It will as mentioned be more brittle and fatigue faster if the axle is under torsion pressure and is actually flexing. If you have a more ductile/elastic axle it will cope with torsion stress more to the point where you could have a crank shaft like example where it will never suffer from fatigue. (crank shafts flex on every cycle but on the stress/strain graph the flex is under the elastic deformation point where the metal is effected - ever, theoreticaly giving a crank shaft an infinite life span). In this case it may not have the absolute strength before breaking.

Toughness not hardness is the quality we would be after here. Toughness means it has largish elastic deformation and is still not to ductile where it will plastic deform, again inducing necking and fatigue. Toughness is not all that related to hardness (that was the only thing that got me worried with the heat treater guy, he was only interested in hardness). So assuming we have a quality steel to work with heat treating is very effective and many properties can be given to steel through the process. (if anyone is interested look up youngs modulus) If we have crap steel then it may be hard to improve the axles at all! - nuts.

The main thing I would still need is an accurate idea of what they are made of there is no easy way of finding this out.

Originally Posted by F4Phantom

I called a heat treater to ask about axles, he already does rally car axles and has not had them break after treatment. He uses rockwell hardness before and after to work out if he has made them harder.

This is where it becomes complicated as I would have thought in axles its toughness we would be after instead of hardness.

So anyway he wants to know what the axles are made out of, so if anyone knows any industry standard numbers, codes used to describe the type of steel a stock RRC axle is made from please let me know. Then he can give me a difinitive answer to an outcome.

For $80 per axle its a cheap upgrade. He also said quantity would decrease the price.

F4Phantom,
i am sorry to say this,
but to do what you suggest would be a waste of time and money.
your advisor , although knowledgable in his trade perhaps, is suggesting that a major manufacturer doesn't know how to make an axle.
crap.
the often stated, but not correct, assumption that lr axles are weak, stems mainly from the fact that so many lr's are on the planet and many of those have been modified way over their intended design limits.
a normal lr of any series, is able to give excellent service in standard form.
it's when you modify the vehicle that the problems begin.
if you want to waste your money and help your heat treatment mate get his kids through school, just give him a donation, and save yourself the wasted time lost in pulling your axles out for him to bugger up.
mobs like maxi and now hi-tuff make axles that are far stronger than the original items - they are also larger in diameter and use far better steel than was available to the manufacturer in the days of the earlier series vehicles.
for $80 per axle, it's a waste of money.
he wants to know what the axles are made out of?
huh? he's wanting to heat treat them, why doesnt he find that out, that's his friggin business!
[yep, i am watching the swear filter!!!]

thank christ i didn't see your last post before i posted this.

Originally Posted by harry

F4Phantom,
i am sorry to say this,
but to do what you suggest would be a waste of time and money.
your advisor , although knowledgable in his trade perhaps, is suggesting that a major manufacturer doesn't know how to make an axle.
crap.
the often stated, but not correct, assumption that lr axles are weak, stems mainly from the fact that so many lr's are on the planet and many of those have been modified way over their intended design limits.
a normal lr of any series, is able to give excellent service in standard form.
it's when you modify the vehicle that the problems begin.
if you want to waste your money and help your heat treatment mate get his kids through school, just give him a donation, and save yourself the wasted time lost in pulling your axles out for him to bugger up.
mobs like maxi and now hi-tuff make axles that are far stronger than the original items - they are also larger in diameter and use far better steel than was available to the manufacturer in the days of the earlier series vehicles.
for $80 per axle, it's a waste of money.
he wants to know what the axles are made out of?
huh? he's wanting to heat treat them, why doesnt he find that out, that's his friggin business!
[yep, i am watching the swear filter!!!]

thank christ i didn't see your last post before i posted this.

Yeah you make some sense and I have not broken one yet either! but I have seen them snap all too easily on locked RR's and as I am under consideration for some type of locking device this is one idea. I HATE WASTING MONEY.

F4 , I'm afraid I agree with everyone else here, you are wasting you money.

Hardening axles makes them rigid , Axles must have elasticity so that when torsional forces areapplied they can twist and when these forces in action are removed they will wind back to original form , however with rigit axles they won't swing back and will most likely snap , if it was that easy to strenghten axles we'll all be doing it and not bother buying upgrade axles like Mccnamurra or hytuff.