Chassis welding, ARK or MIG ?

[Kev80]

Ive got a few cracks on the Hilux chassis just forward of the steering box, whats the best way to fix this ?

Id like to MIG weld it but i only have an ARK welder, will this be ok ?

Cheers,

["CANADA"]

make sure you drill a small hole at each end of the crack

[Kev80]

Umm, i think you ment cracks.

I have heard of this, sounds weird considering it will be welded over hey.

[mavzilla]

the drill hole stops the crack ( or cracks) from spreading from under the weld as you can only weld one side

[Kev80]

Good point, will do this before welding.

[V8Patrol]

To pass ones chassis welders ticket you must do it using ark..... not that its relevant here tho.


For starters use a grinder and "Vee" the crack out as best as you can from the most difficult side to get to
Then run a verticle down weld over the "V" you've ground out.
Re-grind the vee cut but not as deep and repeat the verticle down weld again...... do this untill you have atlease 1/4 of the chassis thickness in weld height above the normal chassis height ....
IE:
if for example the chassis is 4mm thick then the weld when finished on that side should be 1mm proud of the sorounding chassis height.

Then on the side thats easy to get access to repeat the whole thing..... only Vee cut into the weld you've put on the other side by atleast 1mm.

Dont run too high a setting either..... better result with a cooler arc temp than a hot one regardless whether its mig or arc.


General rule of thumb between passes:
If you cant place ya hand directly on the weld and leave it there for a minimum of 30 seconds then the chassis material is still to hot for the next weld .... go n make a coffee of have a beer instead while it cools down naturally.
Do NOT quench with water or commpressed air to speed up the cooling process ...... chassis welding requires patitence.

Kingy

[Mudsierra]

To pass ones chassis welders ticket you must do it using ark..... not that its relevant here tho.


For starters use a grinder and "Vee" the crack out as best as you can from the most difficult side to get to
Then run a verticle down weld over the "V" you've ground out.
Re-grind the vee cut but not as deep and repeat the verticle down weld again...... do this untill you have atlease 1/4 of the chassis thickness in weld height above the normal chassis height ....
IE:
if for example the chassis is 4mm thick then the weld when finished on that side should be 1mm proud of the sorounding chassis height.

Then on the side thats easy to get access to repeat the whole thing..... only Vee cut into the weld you've put on the other side by atleast 1mm.

Dont run too high a setting either..... better result with a cooler arc temp than a hot one regardless whether its mig or arc.


General rule of thumb between passes:
If you cant place ya hand directly on the weld and leave it there for a minimum of 30 seconds then the chassis material is still to hot for the next weld .... go n make a coffee of have a beer instead while it cools down naturally.
Do NOT quench with water or commpressed air to speed up the cooling process ...... chassis welding requires patitence.

Kingy

X2 except for HHS steels in truck chassis

[Kev80]

Then on the side thats easy to get access to repeat the whole thing..... only Vee cut into the weld you've put on the other side by atleast 1mm.

Thanks for the info, im not sure what you are saying here. The cracks are on the boxed section so you can only weld one side.

Anyway i will try & grind the cracks tomorrow & after welding maybe weld a plate over them.

(sorry for the big pics)

The second pic has a "L" shaped crack to the left.

[ForceAnt]

Also use a low hydrogen rod. Like a 16tc.
cheers Ant