Outer Limits 4x4 Board

I am/was seriously considering longer rear arms for my patrol, and i would love a set of the Superior ones..... but with the amount of crap i want/need to do, i will find funding it a bit tough!! i have a full set of standard arms here that i am going to use for angles and bush sizes......i can buy (read aquire ) 40mm diametre 4140 high tensile steel from where i used to work...... would that be suitable to make trailing arms out of? considering the size of the originals, i would think that solid 4140 would be more than suitable. I would probably weld a strong-back onto it as well....... again, if i can get 40mm, i suspect none would be needed. Maybe 25mm 4140 with a strong-back wleded onto it.
Ideas?

on my ute im using hollow bar, which is something like 40mm od, 20mm id, mild steel, my lower arms are approx 1050 long centre to centre, i have not bent them yet after a nissan trials, willowglen, tuff truck and a few social wheelin trips,

in my opinion stroung enough, but if you got access to better, go for it,

i was thinking of getting some 40mm 4140 and machining a taper on each end and welding the bush housings on the ends. A guy on my forum has a jig for it..... just need to confirm the length of it.

I really have no experience to comment only to say that all the bent factory arm ive seen have appeared to be only thin walled mild steel.

Ive got snake arms now and havnt bent them though the adjustment system is far from perfect unless you like them comming undone all the time..... nothing a couple of 3.2mm rods didnt fix though. maybe their site mentions what material they are made of ?

Would be good to see build pics when you start.

cheers.

I got some made out of 20x40mm RHS it might have a 3mm wall. Its pretty good. Havnt bent them yet and they did atleast the first Tuff Truck before I got them.

i might stick to 25mm 4140 and weld a strong-back on it. I'll be sure to get pics of it when i do it...... either that, or i might go see Brooksy at metaland here in Scone and see what he has there that i could use.

mine are 40mm OD 20mm ID and 20mm longer than standard.
they are plenty strong enough.

to give you an idea standard arm with bushes is under 2kg, mine are 7.7kg with bushes

i currently have 3rd's arms on mine...... and they are big heavy bastards.

I did mine in 50 x 36mm hollow bar. Made them 69cm long seeing as it seemed like a good number at the time. That is about 20mm longer than stock. I'm going to change to a long arm setup soon.

I have been ringing around for prices on steel.
im finding 50mmOD25mmID alot cheaper then 40mmOD20mmID hollow bar.
has anyone got experience with 50 OD 25 ID for trailing arms?
thinking of using it for lowers and 40mmOD 25mmID for upepr arms.

USE ALLOY TWON .......I have sourced some for HYPO for his buggy .......

T6 6061 Solid bar Smart aluminium Prt no BRA0508

50.8 od have alook in HYPO's thread he has machined his up himself look very bling ......

Ben is also running smaller O/D material for his upper links



Antunac runs it T7 (apparently) the rear links in his buggy

Mal in the bushy also runs similar

Dan

Patrolden wrote:i might stick to 25mm 4140 and weld a strong-back on it. I'll be sure to get pics of it when i do it...... either that, or i might go see Brooksy at metaland here in Scone and see what he has there that i could use.

You wont need to add anything to the back of them.

The 20x40 rhs as on Turps above is an easier and strong alternative.
I ran Mal Leslies ones on 2 trucks for 6 years.

Bazzle

Tony im not sure if you are aware but 4140 is not that easy to weld properly I weld it at work we weld clevises onto hydraulic cylinder rods.

It needs to be pre heated to 200-250 deg. not allowed to cool during welding, only welded with low hydrogen electrode and has to cooled very slowly.

If it is not done properly the weld and pairent metal becomes very brital therefor becomes weaker under impact than mild steel.

This maybe a very usless bit of info but may help

Cheers Aza

Aza is right the 4140 has more carbon content as compared to 4130. It is harder but more brittle and welding hardens the heat affected zone making it brittle and prone to cracking. Unless welded under strict conditions mild steel would actually be stronger

A1 wrote:USE ALLOY TWON .......I have sourced some for HYPO for his buggy .......

T6 6061 Solid bar Smart aluminium Prt no BRA0508

50.8 od have alook in HYPO's thread he has machined his up himself look very bling ......

Ben is also running smaller O/D material for his upper links



Antunac runs it T7 (apparently) the rear links in his buggy

Mal in the bushy also runs similar

Dan

bro too late ordered it.
thanks for the tip i should have looked here earlier thats for sure... dang!

I also run 40 x 20 hollow bar lowers and cannot bend them. A mate of mine also runs 40 x 20 and his lowers are 1100mm long and hasn't bent anything in numerous comps and plenty of abuse. This seams to be a great size for control arms.

Last winch challenge at rocky I big time hit air and came back blowing my tyre, mashed my trailing arm mount on my diff and slightly bent my trailing arms "all four". They were standard arms with 8mm flat welded to both top and bottom of the lowers. I can gareentee it was the flat that saved the day.

I have now used 6mm seamless with 25mm by 8mm flat welded to top and bottom for the lowers.

LudaCris

i did the same jump as chris just didn't break my car on that hill and im running modified and lengthened standard arms on bottom, we cut them in the middle and weld bigger tube in over the original no flat bar nothing, none of us up here have broken or bent one yet and we are all pushin over 300 at the wheels with 35's and hate our cars.

A1 wrote:USE ALLOY TWON .......I have sourced some for HYPO for his buggy .......

The aluminium solid bar Dan is talking about is the best option.

I wasted so many links in 40mm hollow bar, 32nb xxstrong and 1.75" cr-mo. All with heavy flatbar welded to the top of them too. They would just end up buckling sideways with the flatbar brace on the top. Been running the T6 aluminium for all of this year and have only just managed to put a slight bow in one link.
I have long links, heavy axles, heavy wheels, big tyres, and I can't drive very well, so my car is a good test bed for link material.