Can I machine something from stronger steel?

[rcx132]

There's some custom made misalignment spacers on the heim joint that holds the rear axle on my Vitara. The joint misaligns when the axle rotates relative to the car. The problem was that with serious rotation, i.e. off road, the heim would run out of misalignment and would start unscrewing the lock nut. Hence these misalignment spacers were made to give extra rotation. You can see the OEM spacers (black, rusty) next to the customer spacers in the photo below (shiney). These photos are three years old now and the spacers have since failed, the groove is too deep, the lip just broke off. So I thought I could get new ones made, but with the groove less deep as that's what weakens them.

So my question is, could I also use some stronger steel? The fabricator who makes this stuff for me knows nothing about strong steels, he's only ever used regular steel from local stock holders. He says he wouldn't even know where to start. Can stronger steel be machined on a lathe? Where do I buy it? What grade should I look for?

 

[Maker]

How did it fail? Has it worn/cracked/deformed/etc?

 

[dobbslc]

I can't see a reason who some stronger Steel can't be used, you'd need to know what type he's been using previously then find the next one up. I wouldn't go mad a use something exotic as it might be too stiff and crack. Also if you have a shallower v grove it would bottom out sooner and break, maybe that's what happened before so a tougher metal would probably still fail

 

[galooph]

You could try 4140 steel, I know it's a popular choice for breech blocks on some of the US gunsmithing forums. I've machined it ok with carbide tooling, but only for basic things like pivots for hydraulic cylinders.

 

[brightspark]

en 19 has good high tensile strength I've machined a few projects with it https://www.smithmetal.com/en19.htm

 

[rcx132]

How did it fail? Has it worn/cracked/deformed/etc?

The sideof the V groove that bears against the spherical bearing just sheared off.

 

[Maker]

If you could cut the groove with a bigger radius in the bottom, it will spread the stress a bit and make it less prone to breaking off. That and use a steel with a higher tensile strength and I think they'll be alright.

I've got some EN24 (AKA 4340 I think) here, I could have a go at making a pair and heat treating them.

 

[rcx132]

If you could cut the groove with a bigger radius in the bottom, it will spread the stress a bit and make it less prone to breaking off. That and use a steel with a higher tensile strength and I think they'll be alright.

I've got some EN24 (AKA 4340 I think) here, I could have a go at making a pair and heat treating them.

I was going to suggest the radius, but thought it could be difficult to cut?

The spacers originally had a 1/2" bolt, I now fitted a slightly smaller M12 bolt (stronger 12.9 grade). That means that the new spacers will be slightly thicker wall.

Happy to pay for your time.

I know nothing about hi-ten steel but was told that too strong a steel results in other problematic side effects.

 

[graffian]

The stronger steels are no problem to machine.

If you don't have a lathe you should be able to buy the spacers off the shelf I have had stock looking spacers and wide centre rose joints,
on things I have altered/fixed/broken.

 

[Hood]

I've got some EN24 (AKA 4340 I think) here, I could have a go at making a pair and heat treating them.

EN24T, lovely stuff to work with, it is what I made my turret from Would you need to heat treat them? Should already be pretty tough, assuming it is T condition?

 

[piman]

Hello RCX,

if I understand you correctly, you are exceding the travel on that joint when off road. I don't see that making it stonger is a gain other than it may not break. When the locator is at it's maximum travel the axle still wants more travel so, to me, a different design is required, something that allows the axle to move as far as it needs without coming to the end of the locators travel. I'm presuming that it keeps the axle central to the vehicle axis, a watt linkage will do that but is quite complicated to make and fit, depending on the room available, but thare are many variations on that theme.

Alec

 

[rcx132]

Hello RCX,

if I understand you correctly, you are exceding the travel on that joint when off road. I don't see that making it stonger is a gain other than it may not break. When the locator is at it's maximum travel the axle still wants more travel so, to me, a different design is required, something that allows the axle to move as far as it needs without coming to the end of the locators travel. I'm presuming that it keeps the axle central to the vehicle axis, a watt linkage will do that but is quite complicated to make and fit, depending on the room available, but thare are many variations on that theme.

Alec

Not quite. I *was* exceeding the joints travel. The custom misalignment spacers fixed that and travel is no longer being exceeded. But they are weak because of the V groove in them.

 

[rcx132]

I've got some EN24 (AKA 4340 I think) here, I could have a go at making a pair and heat treating them.

Let me know how much you want. I don't know if heat treating is needed. I think the combination of the radius, thicker wall (due to smaller bolt) and shallower V groove seeing as I no longer do extreme off roading and probably it was too deep anyway, in combination with stronger steel, should solve the issue.

I only know what people have told me but heat treating can cause distortion right? And DIY heat treating is difficult to control?

If you don't have a lathe you should be able to buy the spacers off the shelf I have had stock looking spacers and wide centre rose joints,
on things I have altered/fixed/broken.

I did look for off the shelf ones, it's just getting the width and bolt size to match. Custom ones are expensive though, my fabricator reckons it's an hours work, he charges £25/hr and need two.

 

[graffian]

They would be no trouble to make. Sounds like you want to find another joint.
Heat treating with a torch is a bit unreliable, OK I am a bit unreliable, and I don't think it's needed for this.
If you have no luck elsewhere send me a drawing with the dimensions, I can't read the one above, or let me have a joint to fit them to.

 

[rcx132]

They would be no trouble to make. Sounds like you want to find another joint.
Heat treating with a torch is a bit unreliable, OK I am a bit unreliable, and I don't think it's needed for this.
If you have no luck elsewhere send me a drawing with the dimensions, I can't read the one above, or let me have a joint to fit them to.

Hi I don't know what you mean by another joint? You mean to ditch the heim and go for a different type of joint?