Rust hole fix

[buhay6]

hey guys well I found a rust hole under my trim today and after pulling all the running board panels off I found a lot more rust but not through yet. It's on the shell I'm building up so I have time to work on it, but my dad told me there's a chemical that you can spray on that completely eats everything but metal and I'm wondering if any one would know what its called because my dad cant remember.
........so much for a rust free shell!!

You must be logged in to view this image or video.

this is the rust hole (passenger side front of the rear wheel well.)

You must be logged in to view this image or video.

second serious spot, almost rusted through you can hear it crack when pushing on it

You must be logged in to view this image or video.

light rust less serious of the lot, both sides.

worse part is my parts car is rusted in all the same spots so I cant just cut and weld in stuff.

 

[sniperelite]

They are called rust inhibitors and are supposed to neutralize the rust to prevent from spreading and getting worse. One of the more popular ones people use here is called POR-15 also I have used Naval Jelly with some good results. YOu can get them from Autozone or Pepboys or Napa any place like that.

However your best route to fix those big rust holes is to get a cutoff wheel and start cutting out around the rust until you hit good metal. From there the best option is to have new pieces of metal welded in place and do some simple body work (bondo/primer/paint) to get it looking like new.

It may seem like a lot of extra work but believe me you will thank yourself in the future that you did it.

 

[buhay6]

The rust hole I am cutting out and have to find a good piece to replace it with but inside the car when I had it stripped the rust was working its way around the wheel well from the inside out and I cant really get at it, Thats my main problem, I need a spray that'll eat that away. You think paint thinner would work?

 

[sniperelite]

NO sir no paint thinner it doesn't neutralize the rust like the other products. You can try to do a couple coats with that neutralizer stuff to spray on the wheel well and let it have some time to work at the rust. YOu will definitely want to spray a few coats of some good Rustoleum paint after the rust preventer has set in and dried to help prevent further rust from happening.

Just remember take your time and try to get as much of it as you can as it will keep your car lasting a few more years longer.

 

[WES_393]

With a rust hole that size you don't want to use Bondo. It will crack, fall out, and just plain look like hell. The only true fix is to cut the rust out and weld on new sheet metal. The rust that you can't get to should be sprayed with rust converting primer before the hole is welded shut.

If you want to get rid of the rust, auto parts stores sell a chemical that does just what you described. It will eat away paint, rubber, and rust leaving nothing but metal. However, the affected area most be soaked in the chemical for a long period of time, not just sprayed on. I would suggest using a whire wheel to remove surface rust and then rubberized undercoating to keep it from coming back. The rust holes that go all the way through will need to be cut out and replaced, there's really no way around it.

 

[sniperelite]

Indeed bondo alone will look like crap and not to anything but be a quick band-aid fix. To go back on my post I recommend welding in the new sheetmetal like I mentioned before and only AFTER that would I recommend some bondo(only if needed obviously) to smoothen out the imperfections between the sheetmetal and original body panel. Of course you will want to apply thin coats evenly and use as little as possible to keep the shape of the body as original as possible.

Rule of thumb the less the bondo you use the better :thumbsup:

 

[TSIturbo91]

Indeed bondo alone will look like crap and not to anything but be a quick band-aid fix. To go back on my post I recommend welding in the new sheetmetal like I mentioned before and only AFTER that would I recommend some bondo(only if needed obviously) to smoothen out the imperfections between the sheetmetal and original body panel. Of course you will want to apply thin coats evenly and use as little as possible to keep the shape of the body as original as possible.

Rule of thumb the less the bondo you use the better :thumbsup:

This is good advice. Before going back to school for HVAC I did auto body work for a few years. Use as much metal as you can and te least amount of bondo. These cars are a unibody design and that means the whole shell is crucial for structural integrity. Bondo will not hold up in a crash. Also any rust left over will continue to grow so as mentioned use a cut off wheel and wire brush or grinder. Plan ahead and if you not sure about something, ask. If your new to welding or out of practice I highly recommend that you do just that and practice. Even pros get "rusty" at it and need a brush up.

 

[buhay6]

I know I have to cut it out and i'm going through that process right now, I bought a dremel 8200 cordless so I can cut the rust out where ever its started. I found a good shell at a wrecker and started cutting the whole section I need out......and ironically the brand new dremel breaks

I hate bondo with a passion I am one of those people that wanna do it right the first time for the last time. I've seen a lot of people who just bondo'd over stuff like that and think they should do body work for a living!

I'm also buying a mig welder because I need it for a lot of parts on the car and to do some work on my buddies beamer. I have 2 year experience with mig but it has been while so ya practice is in order.

Thanx for the help everyone!

 

[jeromea]

I forgot what it was called, but I got a can from Advanced that I used on my 89 Rex, and it did a damn good job at keeping the rust from getting any worse. (especially here in Wisconsin). Like I said I don't remember the name, but it was a blue can with a black top, and once you sprayed it on the rust it turned it completely black. All you had to do was have the area clean, and spray two to three coats depending on the severity. I used a simple wire brush to clean it off before applying the coats.

 

[ricktb]

dont buy a dremel for rust, dremel cost over $100 and theres a cheaper version for like $25 bucks, they WILL die on you the dust from the grinding gets in the motor, it starts to smoke and sooner after cuts out ,sparks or burst into flames.

 

[sniperelite]

Ya buddy dremel is good for small intricate work that doesn't require much cutting power but that's about it.

What you need is to buy yourself a good ANGLE GRINDER and a metal CUT-OFF DISC from home dePOT or somewhere like that. They can be had for usually less than $50 and will work wonders compared to the dremel tool. Just make sure to be careful and not grab the wheel when it still spinning because it has a LOT of power and you will end up with a good chunk of skin off your finger like I have right now :yikes:

It is good that you found a good condition shell to get the clean metal from and using the MIG welder carefully will result in a good long-term fix if you do it right. I bought a big can of bondo when I did this because I had to shape my own pieces of metal for the wheel well and figured it would look like crap w/o a clean finish from the bondo. But I took my time cutting and shaping the metal and ended up completing the job to my satisfaction without even opening the can of bondo (too bad it was past return policy)

Keep us posted on how it goes and let us know if you need other advice. Good luck buddy it will be worth it in the end once it looks nice and clean! :thumbsup:

 

[KROMEkid]

I'm with jermoea on this one. I used Adv Autos rust inhibitor and it worked great on anything. Clean it with alcohol, shoot a couple coats of the rust inhibitor on, and it'll turn it black. It might not stop the rust but it will slow it down substantially.

 

[bryanwheat]

Go to harbor freight and buy a 15 dollar angle grinder. Watch out though because they are pretty powerful and can jump out of your hand if you aren't holding on tight enough.

 

[T is for TURBO]

Watch out though because they are pretty powerful and can jump out of your hand if you aren't holding on tight enough.

Thats what she said

 

[buhay6]

, I have an angle grinder and stuff I just bought the dremel (cost me $160) just for a portable solution. I returned it to day for a new one because the battery blew up already and fried out the charger for it, good ol Canadian tire.....replace and not ask questions!

We don't have harbor freight here in Canada..... well at lest not in any place I know of. We just have NAPA, parts source, Canadian tire, dealerships, and performance plus (AKA ricer central!)
I'll give the rust inhibitor a try on the spots that aren't so bad and where I can keep an eye on them, so if they get bad I can grind it out and hopefully just use the welder to build up the metal and reshape it.

I don't know if I said this before but I plan on also cutting out the rocker panels under the doors to address the rust situation there as well (using factory weld cutting bit) then applying POR-15 inside the panel around where the trim clips into the panel to try and seal it up good and tight and then weld it back in and do the same to the outside. I also have to redo the wheel well coating then I should be done other then some paint work!

I didn't expect near as much interest in this thread but I'm glad people are checking it out, I need as much idea's as possible. Thank you every one!! I will keep you posted, Currently having a freak snow storm so I'll have to wait til friday to do anything more on the shell.