two frame repair questions

[johnunit]

I found out my "minor frame rot" right behind the front right wheel is a bit more advanced. I'm going to end up plating or replacing everything on the inner side of that weld on the torque box, and the area around the trans crossmember mount. This isn't an issue as I work with a certified welder, but I have two questions:

1. are there any non-obvious frame rot places to check? I know there's some thin spots in front of the crossmember on the driver's side but the rear frame horns and around the rear axle look solid, as does everything else I could see on the main frame rails under the doors.

2. how should I support the front of the car while doing this welding? If I'm going to be cutting the stuff out, I'm sure it'll sag if it hasn't already. Should I be supporting the front crossmember? The right front control arm? Maybe somewhere under the doors? If I'm going to weld it all up I want it to be welded, you know, straight. The lift points with the hoist I have are right on the frame in front of the rear wheel and behind the front wheel, if that makes a difference.

[jaywish]

I am guessing the car will be up on a lift?

Are you going to be able to do the welding without removing the lower control arm?

IMHO you will have to do some guestimating. If you make sure the frame on both sides are the same distance above the ground you would think that setting the bullnose heights the same before your weld job would be right. I don not think it is because the left side will be flexed down. If you weld the right side it will not be flexed and the left will. So you would probably need to make sure the right bullnose is a bit (guesstimate) higher than the left. Again assuming the frame height from ground is the same right and left.

[johnunit]

I am guessing the car will be up on a lift?

Are you going to be able to do the welding without removing the lower control arm?

IMHO you will have to do some guestimating. If you make sure the frame on both sides are the same distance above the ground you would think that setting the bullnose heights the same before your weld job would be right. I don not think it is because the left side will be flexed down. If you weld the right side it will not be flexed and the left will. So you would probably need to make sure the right bullnose is a bit (guesstimate) higher than the left. Again assuming the frame height from ground is the same right and left.

yes, the car will be on a lift. I'm not welding near that near the front suspension. In this picture, I would be welding the dark/rusty area directly to the left of the cat in this picture, and the area around the transmission crossmember



What do you mean by bullnose?

[jaywish]

Bullnose = the end of the frame.

[turbo2256b]

I have found the area right side front torq box and the frame to the rear torq box rust issues my be traced back to the battery acid or fumes in a lot of cases. Before I have replaced these sections I wash them out wit ha water baking soda mix to neteralize any acid.