Thread: What steel are king pins made from ?

Thanks AT4 Yes been to AAA a few times over the years , mainly to buy hard to get hub seals . Trouble is, I need 9.010" as a a final diameter which is a size I doubt I could by off the shelf . Can somebody tell me what's the difference between EN36A and EN36B grade steel ?

I think the discussion above describes the exact material and heat treatment of MacPherson struts and most hydraulic cylinder rods.
In addition to the material specs and case hardening, they additionally have hard chrome plating and are precision ground.
AND they are available VERY easily, both used and new in any length.
If you want to go that route and have trouble finding them in the right size, don;t hesitate to yell out - I have good sources.
DO let us know the dimensions required, others here may already have what you need.
By the way, last time I replaced king pins, they took one heck of a press to get them out and new ones back in..... (into the axle bore)

Don't know what the difference is between en36a and b is but I'm pretty sure en36b isn't available in Australia.

Ian Stainsfield-Smith in Hallam has EN36A available in a few diameters

En36A has slightly lower carbon than En36B so it's better to machine without coolant as it resists hardening while heating where higher carbon steels will harden up if you heat them too much during machining . Slightly more chromium than En36B . Fairly similar steels but en36a is easier to work with .

Originally Posted by morrisman

Thanks AT4 Yes been to AAA a few times over the years , mainly to buy hard to get hub seals . Trouble is, I need 9.010" as a a final diameter which is a size I doubt I could by off the shelf . Can somebody tell me what's the difference between EN36A and EN36B grade steel ?

9.010" LOL What is it for?
Will

Bit late, not kingpins, but I've made "live" spindles out of 4340, Bohler supplied that too.

The mention of 40s tech reminds me the go to material back then, for all that stuff, post war was railway car axles, so presume BHP was actually pouring some good alloys back when. Irony is, far greater range of metals were produced locally 50 years ago than now....where we're lucky to get hot rolled and colourbond.

Originally Posted by Hunch

Bit late, not kingpins, but I've made "live" spindles out of 4340, Bohler supplied that too. Irony is, far greater range of metals were produced locally 50 years ago than now....where we're lucky to get hot rolled and colourbond.

Yes and they were manufacturing steam locomotives here in Australia as well . Where has all of that skill and technology gone ! GMH were manufacturing marine diesel engines during WW2 , including the injectors

Originally Posted by morrisman

GMH were manufacturing marine diesel engines during WW2 , including the injectors

Not to mention building Gypsy Major aircraft engines for training aircraft, and overhauling V12 Alison engines for the US 81st Air Depot Group in a purpose built factory in Brisbane. These were used in the Kittyhawk fighters, among many other aircraft types.

Frank.

I solved the king pin dilemma . A friend in the UK posted me a set of NOS king pins plus other bits - all free . It helps to have friends in the right places. The spring shackle pins , looks like I will be making these . I think 4140 is OK ? The thread on the thinner pin , I think is BSF . Any suggestions ? I think the originals were case hardened. Will 4140 be strong enough ?

If you make the pin out of 4140, you can finish it to size then get it nitrided. It wont distort when it is nitrided, but the case depth will be pretty shallow. Other option would be to use EN36a and get it case hardened, you will get a little bit of distortion so you will need to either hard turn or grind to finished size. The heat treaters will also be able to mask the thread so it doesn't go hard. Unless you are going for 100% original resto, i would make the thread UNF, BSF is too hard to get nuts for.

Where in Melbourne would discerning members go to for for shaft hardening and grinding?
Bill.