Stubborn (Deep) Paint Chip - Going to Try Bondo, Need Help

[3002 tii]

My 135i is Le Mans Blue and I have a stubborn paint chip on the lowest part of the driver's side door. It is deep, down to bare metal and about 1/8" in diameter. For the past 3 weeks, I've tried to repair it using a combination of Langka & factory touch-up pen and I've gone as long as week to let the paint cure. But once I apply the "Blob Eliminator" the paint comes off very easily, and humidity has not been a factor. I suspect the chip is so deep, it really requires a layer of primer which is why the touch-up paint won't adhere.

I'm going to remove the factory touch up paint and try this once more. Question is, given how deep the chip is, should I be applying bondo, primer or perhaps both? There's no dent; it's just paint removed and bare metal exposed. If I do go the bondo route, I was going to buy this. My initial thoughts on process:

1. Remove the touch-up paint, use sanding pen to clean out chip
2. Tape off surrounding area.
3. Apply small amount of bondo
4. Wetsand with 80 grit
5. Finish off with 2000 or 3000 grit
6. Apply 1 coat primer
7. Apply 1-2 coats of touch-up paint
8. Apply 1 coat clear coat
9. Polish

Am I over thinking this? Can I just skip the bondo and go straight to primer if there's no body damage?

[cheshirecat79]

IMO, you're overthinking it. Do you have any pictures of the chip? Also, are there any contaminants inside of the chip that are loose and possibly not giving the paint a solid surface to adhere to? you definitely may want to use the fiberglass pen to make sure everything is out of the chip before filling it in.

Also, when filling the chip, make sure to let the coat dry before applying more paint. Fill-let dry. Fill- let dry. Do this until the paint is filled.

The blob eliminator is supposed to take paint off- the point of the product is leveling off the paint so that you don't have raised "blobs". You could always just sand it down, but the blob eliminator may be better in your case since it won't affect the surrounding clear. If you're comfortable wetsanding, go for it, but remember that the surrounding clear coat is VERY thin.

IMO, you should be able to get away with just filling it with paint, leveling it off, and throwing some clear on top followed by a moderate polish.

[3002 tii]

Originally Posted by cheshirecat79

IMO, you're overthinking it. Do you have any pictures of the chip? Also, are there any contaminants inside of the chip that are loose and possibly not giving the paint a solid surface to adhere to? you definitely may want to use the fiberglass pen to make sure everything is out of the chip before filling it in.

Also, when filling the chip, make sure to let the coat dry before applying more paint. Fill-let dry. Fill- let dry. Do this until the paint is filled.

The blob eliminator is supposed to take paint off- the point of the product is leveling off the paint so that you don't have raised "blobs". You could always just sand it down, but the blob eliminator may be better in your case since it won't affect the surrounding clear. If you're comfortable wetsanding, go for it, but remember that the surrounding clear coat is VERY thin.

IMO, you should be able to get away with just filling it with paint, leveling it off, and throwing some clear on top followed by a moderate polish.

Trust me, after the first attempt I went really thin on the coats and gave it 1-2 days before applying the next coat. It's been a 3 week process to fill in a tiny chip. But right when I'm content with the paint, the second I apply the blob eliminator it all comes off. I'm using a terry cloth with a hard plastic card underneath so it's not like I'm applying uneven pressure. I'm wiping across the surface but for some reason paint won't cure.

And yep, that's what I meant by the sanding pen. I have a fiberglass pen which I used to clean everything out from the beginning. I think the issue is i don't have any primer.

[cheshirecat79]

Originally Posted by 3002 tii

Trust me, after the first attempt I went really thin on the coats and gave it 1-2 days before applying the next coat. It's been a 3 week process to fill in a tiny chip. But right when I'm content with the paint, the second I apply the blob eliminator it all comes off. I'm using a terry cloth with a hard plastic card underneath so it's not like I'm applying uneven pressure. I'm wiping across the surface but for some reason paint won't cure.

And yep, that's what I meant by the sanding pen. I have a fiberglass pen which I used to clean everything out from the beginning. I think the issue is i don't have any primer.

That's really surprising that the paint is pulling up that much. You sound like you're doing everything correctly. I agree that that this point you need to throw a bit of primer under there and fill the hole with something the paint can affix to. Quick question, though, do you think it's possible to not use the Langka at all and try to top it off with a clear before you get to the point that you have excess paint over the top of the surface? If so, you may be able to get away with just wetsanding the clear down to a uniform surface and buffing it out.

Typically the Langka is used to remove excess paint that's already cured for a while. When I've used it (doing the same method you're using) it's taken a bit of waiting for the solvent do work it's magic for it to really make an impact. Sounds like maybe it might be best to try to use the Dr. Colorchip method and use a latex glove to sort of "smudge" the paint into the chip and use a mild solvent to remove excess smudged paint from the clear coat around the area before topping it off with a clear.

[3002 tii]

Originally Posted by cheshirecat79

That's really surprising that the paint is pulling up that much. You sound like you're doing everything correctly. I agree that that this point you need to throw a bit of primer under there and fill the hole with something the paint can affix to. Quick question, though, do you think it's possible to not use the Langka at all and try to top it off with a clear before you get to the point that you have excess paint over the top of the surface? If so, you may be able to get away with just wetsanding the clear down to a uniform surface and buffing it out.

Typically the Langka is used to remove excess paint that's already cured for a while. When I've used it (doing the same method you're using) it's taken a bit of waiting for the solvent do work it's magic for it to really make an impact. Sounds like maybe it might be best to try to use the Dr. Colorchip method and use a latex glove to sort of "smudge" the paint into the chip and use a mild solvent to remove excess smudged paint from the clear coat around the area before topping it off with a clear.

I tried Dr Colorchip before on light scratches with success but was never satisfied with the final result when it came to chips, hence why I tried Langka this time around. I think Langka works well on areas that are parallel to the ground, .i.e. hood, trunk, etc. But being that this is on the door, even though I don't put that much on where it drips -- it still doesn't dry correctly.

I just ordered a primer & paint stick from paintscratch.com. I'm going to try to repair this the traditional way. No magic blob eliminators, just patience and the right tools.

[E82MSport]

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