Truck Frame Welding

[Fastfish]

My Brother inlaw has a work van that has some big rust holes in the frame. (GMC full size van) I just welded some mild steel (3/16) plates over the holes. used a Mig 175 with flux core mild steel wire. (I can weld ok) .Question is, was this a bad thing to do interms of creating stress concentrations around the welds? Thanks.

 

[EOC_Jason]

Welding gusset plates like that I don't think could hurt anything.

 

[Professur]

You'd normally taper fish plates to ensure that the edges don't cause transition points at the ends.

 

[steel 35]

You'd normally taper fish plates to ensure that the edges don't cause transition points at the ends.

Never vertical

 

[sberry]

Don't worry about it, got to be better than it was.

 

[Mr.N]

Make sure what your welding to is solid

Don't expect the patches to last much longer, its rusting for a reason and it will continue. Expect there to be other areas that will need repair once you start looking.

 

[Fastfish]

Re: Truck Frame Welding - Thank you and another question

Thank you to all who replied. I was really worried for a while. I will be sure and check the frame out next time my bro inlaw comes over. I plan to do more of this in the future and possibly build an ice race car. I need a plasma cutter next to make gussets and other brackets...... Question is: does a plasma cutter leave an edge like oxy/acc cut? is it more or less rough? Thank you

 

[CNGsaves]

Really depends on the vehicle . . .
. . . .
If the van looks like pic below, then tell BIL that van is unsafe. You'd be more than happy to take off his hands for $1K and fix frame properly !

Then get busy welding to box the whole frame !! Problem solved.

 

[creativecars]

Re: Truck Frame Welding - Thank you and another question

Thank you to all who replied. I was really worried for a while. I will be sure and check the frame out next time my bro inlaw comes over. I plan to do more of this in the future and possibly build an ice race car. I need a plasma cutter next to make gussets and other brackets...... Question is: does a plasma cutter leave an edge like oxy/acc cut? is it more or less rough? Thank you

A plasma will cut as smooth as your hand can move. And leave just a bit of slag on the back side. One quick swipe of a grinder and it is gone... So much smother than a oxy/acc for me. But there are some guys that are "good" with a torch and can cut almost as nice as a plasma. That is not me. I just cut and grind.

 

[MoonRise]

Re: Truck Frame Welding - Thank you and another question

... Question is: does a plasma cutter leave an edge like oxy/acc cut? is it more or less rough? Thank you

Generally, an air-plasma cut on mild steel will have a significantly smaller HAZ than an oxy-fuel cutting torch on the same mild steel, due to the faster travel speed of the plasma and no pre-heat flame like the oxy-fuel cutter has.

The cut-edge quality can be as-good or better than an oxy-fuel cut edge. If the amps and travel speed are set 'appropriately' for the metal thickness, plasma can usually leave a cut edge with just a tiny bit of easily removed dross on the 'back' of the edge.

A bit operator-skill dependent though.