[mstrjon32]

Alright, so I asked about this on the Sky forums (since I drive a Sky) but they're too preoccupied with telling me I need psychiatric care or calling each other cranky old men to say anything constructive. I thought I'd ask over here where I usually find the answers to actual problems in my searching.

The story is that a few weeks ago my Sky got banged on a drive-up lift (of all things). Not on the fender, but much more annoyingly, on very-difficult-to-replace rocker panel below the driver door (and ever so slightly on the passenger side, to the point where I'm not worried about it at all). The metal got pressed in just next to the seam, and in one area, about a few cm long, it actually got scratched right down to the metal. I'd pretty mad at the idiot who let this happen and was driving the car up onto the lift, but unfortunately it was myself. :brentil:

Alright, well, I did a few things to try and rectify this. First, I wrapped a screw driver in cloth, and then bent the metal back down to the correct shape. Then, I cleaned out the scratch with some soapy water, dried it, and then applied 3 coats of touch-up paint. Finally, I looked under the lip (as if you were under the car on a lift, looking into the rocker panel) and noticed that in bending the metal back down, I managed to put a few gashes in whatever rust proofing material is on the chassis. Alright, I cleaned this with some alcohol, and sprayed a wax-based undercarriage protectant on there. The service manual says to use this X-121B product, but that is impossible to find in Germany, so I found what I thought was the most similar in composition and used that.

So, fine folks, I have a few lingering concerns:

1. Is the metal adequately protected from corrosion with just the touch-up paint? I think that it is not, and there should be primer on there, but I'm hesitant to sand it off and apply primer because the more I work this, the bigger the repair area becomes.

2. What is the stock chassis coated with? It doesn't seem to be a wax-based product, but it sure did mar easily. Is it galvanized (it looks awfully uniform)? Is there something better I can put on there (even though it would be a pain to remove the wax coating now)?

I appreciate any useful advice. You can't see this damage unless you are on your hands and knees, but like I said, my main concern is that I've damaged/improperly repaired the corrosion protection.

Here's a photo of the already touched up scratch, if it's of any value to you:

 

[Robssol]

3M paint defender is my first thought. It supposed to protect your paint, but I would think it would also protect the metal underneath. Or you could repaint the whole car:devil:

 

[chickenwire]

Primer is just to promote adhesion - it doesn't do anything to protect the metal. I think you're protected, but as always look forward to the input and thoughts of others.

As for the chassis coating, beats me. I thought the frame was aluminum? I thought mine was just painted but would have to look closer.

 

[chickenwire]

Oh, and I believe most of the members hear are cranky old men currently undergoing psychiatric care.

 

[TomatoSoup]

I would have used a zinc-based primer first if I were doing it, but too late at this point. I'd just leave it now, but monitor it to see if any rust starts at the repair. If it does, you can sand it down then and do it over.

As for the frame, not sure which coating you mean, I believe it's painted. If you mean the thick, rough, silver strips in your photo, that's panel bonding 'glue'.

And no, CW, the frame is steel, not aluminum.

 

[R&T]

All modern cars are E-coated at the factory. That goes on before a primer and it keeps rust from spreading under the paint or it is suppose to anyway. I would use some touch up primer and paint then clear coat it. You can get the small applicators at the auto parts store or get them from GM if you are worried about the rust. Are you sure it went down to the metal? I can't tell from the pic. It will not be perfect but it will be cheaper than having it professionally fixed.

 

[TX08manualGXP]

for the exterior, I'm with chicken on that. as long as your touch up paint dried properly and does not bubble, I'd consider it done. for the underside, it's pretty much the same, as long as you cleaned and dried and have coated it with some sort of exterior paint, primer, sealer, I'd consider it protected. And I too thought the frame was aluminum.

 

[mstrjon32]

3M paint defender is my first thought. It supposed to protect your paint, but I would think it would also protect the metal underneath. Or you could repaint the whole car:devil:

I've heard of the 3M paint defender before. I think I might actually apply this pretty high up on the rocker panels on both sides of the car once I'm happy with the repair job for the driver side. As it is, I'm getting lots of rock chips between the driver door and the rear wheel.

Oh, and I believe most of the members hear are cranky old men currently undergoing psychiatric care.

At least they're getting the help they need.

I would have used a zinc-based primer first if I were doing it, but too late at this point. I'd just leave it now, but monitor it to see if any rust starts at the repair. If it does, you can sand it down then and do it over.

So, this happened on a German holiday--in Germany absolutely everything is closed on Sundays and holidays, so I wasn't able to pop down to the store to buy any, and I didn't want to wait and give the gash time to start developing rust, so I cleaned it and put the touch-up straight on. I suppose I'll keep my eye on it, and if I notice any rust bubbling, I'm sanding it right down and priming it. I did buy some primer which claims to be for "light to medium corrosion," and the can itself claims that you should up to the zinc primer for heavy corrosion, which I don't have, so I didn't buy that one. Maybe I'll exchange it and use the zinc primer anyway.

As for the frame, not sure which coating you mean, I believe it's painted. If you mean the thick, rough, silver strips in your photo, that's panel bonding 'glue'.

And no, CW, the frame is steel, not aluminum.

All modern cars are E-coated at the factory. That goes on before a primer and it keeps rust from spreading under the paint or it is suppose to anyway. I would use some touch up primer and paint then clear coat it. You can get the small applicators at the auto parts store or get them from GM if you are worried about the rust. Are you sure it went down to the metal? I can't tell from the pic. It will not be perfect but it will be cheaper than having it professionally fixed.

For the frame, I'm just talking about the overall coating on it. I know it's steel, and something is preventing it from turning to rust immediately. I suppose it is an e-coating, because it seems relatively durable, but not that durable (since I seem to have made a gash in it pretty easily--you can't see it in the photos I posted, it's under the lip of the body panel).

It's probably hard to tell from the photos because there are already 3 layers of touch-up paint on it. It definitely went down to the bright, shiny metal. I actually took it to be professionally fixed but the body shop owner insisted that it wasn't necessary and that it would be fine with the touch-up paint. I guess I'll just have to believe him and try not to let it bother me.

For the underside, I put a coat of this stuff in the brown can on it. Who knows if it's actually worth anything, but that's what the guy at the parts store said to use.

 

[The_Ghost]

I can tell you from experience that you should be okay. From my rocker panels to about 1/2 way up my doors behind them is an absolute mess. The PO must have lived on a dirt road. The dealer tried to "touch it up", but made a complete debochery out of it. I haven't had an issue....yet. I am going to get some 3M paint defender this year and spray the areas and make sure there is no new bare metal showing before hand.

 

[R&T]

I don't know about the frames being e-coated but the body is. I'm not sure what type of paint they use on the frames but it has to be pretty strong.

 

[TX08manualGXP]

mstrjon,

with you being in Germany, I'd bet the products you have are far better than what we can get our hands on in the US. the EPA has limited the available chemicals all the good stuff we could use back in the 80's are gone. I'm sure the products you have will suffice.