Rusty Rear Frame Repair

[OldSlowReliable]

So, I got 2 holes....in my frame (teehee)

 

And, I was planning on doing them this weekend, but ended up sleeping for almost the entire weekend....anyways, I'm starting to formulate how ima do it, and I'm gonna go practice more welding tomorrow with my 90amp FCAW from harbor freight...

 

I grabbed a 3' stick of 3"x1/8" steel for the repair, and have a couple questions that I can't seem to get a clear answer for.

 

This is my attack plan.

 

1- Wire brush the rust flakes away.

2- Grind the area down to nice shiny metal

3- Cut the new steel into a /_______\ form and trim to fit

4- Clean off the replacement steel nicely

5- Clamp new steel onto frame and tack in place

6- Weld in increments as to not overheat/warp it

7- Flap disk the finished welds all clean and paint with rustoleum (surrounding frame will be coated with rustoleum rust convertor)

 

 

Now, here are my questions.

 

After I grind the rust off of the area I'm patching over, should I coat all but the area where my welds will reside with rustoleum as to stop it from being exposed bare metal underneath my patches?

 

Will a 90 amp flux be strong enough? although, anything is an improvement over a rust hole..

 

Should I be horribly worried about my gas tank during all this? Its kinda worrying me now!

 

My gas cap is pressurized sorta, as in I unscrew it, and it goes HISSSSSSSSS with air escaping, so does this make it more safe to weld near? knowing that the gas is being trapped inside the tank?

 

What is the best choice for cleaning off the rust and prepping? I'd think a flap wheel or a grinding wheel...

 

Should I drill a hole or two in the patch steel for helping drainage and flushing out the frame, or just leave it as a solid piece? Or even drill a hole just through the patch steel, and then weld in the pit that it formed.......

 

 

 

 

 

and onto the gas tank, and the passengers side.....HOW worried should I be about the gas tank and fuel lines? I'll probably grab a welding blanket from HF and throw it over that whole opening (including the filler lines)

[nunya]

For your coating the area with somethign before covering it question, I haven't looked into it yet but one of my friends who is a bodyman said they have a 'weld through' primer thats avalable in a spray can. Was tellign me about it since he knows I'm gonna do things myself and see how long it lasts before he has to fix it, and he likes when it takes a long time to get to that point. Might be something to look into.

[OldSlowReliable]

For your coating the area with somethign before covering it question, I haven't looked into it yet but one of my friends who is a bodyman said they have a 'weld through' primer thats avalable in a spray can. Was tellign me about it since he knows I'm gonna do things myself and see how long it lasts before he has to fix it, and he likes when it takes a long time to get to that point. Might be something to look into.

Yeah, I was also looking into that......but can't find anyone who stocks it. From what I can tell, after it dries, the heat of welding just mixes it into the metal instead of heating it up and burning it off.....making it ideal for protecting the spots that are gonna be covered up.

 

I think I'll not end up doing plug welds, just stick with the around the edge

[maxwell]

Weld with the fuel tank full, less fumes that way. I welded mine and I could smell gas but I had the body off and covered the tank with a wet towel. Don't worry about drilling holes the rear is the highest part of the frame. The area you are welding is past all the suspension points, I wouldn't worry about warpage especially with 1/8 material. I used a hammer instead of a wire brush then an angle grinder to cut out the pieces, you might be all day with step 1 and 2. Good luck and be patient.

[adamzan]

Wow, you must really love your truck, maxwell.

[GrimGreg]

I dropped the tank the first time I did frame repairs, but I had to patch right next to it then. This year's repairs I wasn't near the tank, but I was near the fuel lines, so I just wrapped them in leather (more to deter a stray arc than anything else).

[MikeV]

full tank, and I use a weld blanket,

I also dropped my tank the first time;

after that I just throw a blanket over it, I plasma cut, weld, grind without issue.

Always have an extinguisher ready and pay attention to the gas lines on the passenger rail.

(Por 15 makes 2 products called Marine Clean (degreaser/cleaner) and Metal Ready (paint/weld prep)) yeah I like POR-15...

Don't worry about the inside as once you weld it any paint etc... is vaporized and the rest of the frame isn't treated on the inside.

2 bad there is no bridge over Lake Michigan; would have you bring it over

 

Addicted to Welding.............

Beats the hell out of my daytime IT job...

Edited October 27, 2009 by MikeV

[OldSlowReliable]

full tank, and I use a weld blanket,

I also dropped my tank the first time;

after that I just throw a blanket over it, I plasma cut, weld, grind without issue.

Always have an extinguisher ready and pay attention to the gas lines on the passenger rail.

(Por 15 makes 2 products called Marine Clean (degreaser/cleaner) and Metal Ready (paint/weld prep)) yeah I like POR-15...

Don't worry about the inside as once you weld it any paint etc... is vaporized and the rest of the frame isn't treated on the inside.

2 bad there is no bridge over Lake Michigan; would have you bring it over

 

Addicted to Welding.............

Beats the hell out of my daytime IT job...

theres a ferry!

 

Naw, Im an avid welder too....just don't like FCAW with this new mig (spatter)

[nismothunder]

Easy,bang the flakes out with a hammer then attack it with a wire brush to clean it up and to get any crap left over before sanding it.I would drill any flowage holes on the side but if your putting a plate on the bottom then yeah,it will let the crap get out unlike the stock flowage holes.I cant think of any thing else,but make sure the battorys disconnected.