Removing minor dieback

**tguil** · 03-06-2013, 09:40 PM

The hood on my white Ram was recenty repaired and repainted. The repair involved a small dent in a corner of the hood. The repair was made and base coat was blended into the factory paint....a very good job on this part of the repair. The whole hood was then cleared using a "coat and a half process" which gave a sufficient mil thickness. However, there was a bit of "dieback" in the clearcoat. The body shop lightly sanded the whole hood with Trizact 3000 and then buffed the hood with a rather mild polish. I think the approach maybe could have been a bit more aggressive because there still is a bit of the "dieback" present. It is visible only under fluorescent lighting.

I am quite sure there is enough clear for a little more buffing. Right now I am planning to use a Porter Cable PC and foam pads to smooth things out a bit. (I don't want to use my Makita Rotary unless I really have to.) I have only Meguiar's products available in my arsenal....Meguiar's maroon cutting pads, Meguiar's polishing pads, Meguiar's Ultimate Compound and Ultimate Polish. Basically pretty safe stuff and I am in no hurry to get this done...the reason for using the PC rather that the Rotary.

I don't want to do any more sanding because it might make the surface too smooth. My Ram is blessed with considerable factory orange peel.

Any suggestions on using these products.

Oh, I could have pushed for more work to be done by the shop, but I chose not to. I tend to be more cautious than most body techs. If for some reason the paint "goes south" in a year or two, I'll plead ignorance and have it redone.

Again... the dieback is in the clearcoat only.

**Setec Astronomy** · 03-06-2013, 10:21 PM

Well, I think you should--wait, what is dieback?

**Pureshine** · 03-06-2013, 10:35 PM

Originally Posted by Setec Astronomy

Well, I think you should--wait, what is dieback?

+2 what is dieback?

**Setec Astronomy** · 03-06-2013, 11:08 PM

"Die Back is the loss of gloss after application (if using glossy topcoat). It is caused from improper evaporation of solvent, poor initial cure, or paint not flattened sufficiently."

**tguil** · 03-06-2013, 11:23 PM

Originally Posted by Setec Astronomy

"Die Back is the loss of gloss after application (if using glossy topcoat). It is caused from improper evaporation of solvent, poor initial cure, or paint not flattened sufficiently."

Yep, that's it. The shop owner thinks the temperature in the booth might have been off just bit...sort of funky weather when the painting was done. This is a a "state of the art shop" with well trained techs. The condition is most certainly not bad enough to justify more paintwork. I can only see the "dieback" through my trifocals in just the right light. It actually looks a bit like "micro orange peel" or perhaps an egg shell. (Yeah, I'm an "old guy"...been messin' with detailing for over fifty years.)

**Setec Astronomy** · 03-06-2013, 11:26 PM

Mike Phillips is the guy to answer this question.

**tguil** · 03-07-2013, 09:25 AM

Sometime in the next day or two I plan to "get at it". I know that "least aggressive" is best, but the clearcoat has been on the truck for three months. I'm thinking about using Meguiar's maroon cutting pad with Meguiar's Ultimate Compound and then follow up with Meguiar's Ultimate Polish on a Meguiar's polishing pad. (I've used the maroon pad with PC before and didn't have any problems.) From what I have read, the Ultimate Compound and Polish are more user friendly than Meguiar's 105 and 205 and with patience they can still "get-r-done".

Any suggestions? If there might be a better product combination using a PC rather than a Rotary or more sanding, I most surely will consider it.

In direct sunlight the "dieback" is not visible.

**BobbyG** · 03-07-2013, 09:36 AM

Originally Posted by tguil

The hood on my white Ram was recenty repaired and repainted. The repair involved a small dent in a corner of the hood. The repair was made and base coat was blended into the factory paint....a very good job on this part of the repair. The whole hood was then cleared using a "coat and a half process" which gave a sufficient mil thickness. However, there was a bit of "dieback" in the clearcoat. The body shop lightly sanded the whole hood with Trizact 3000 and then buffed the hood with a rather mild polish. I think the approach maybe could have been a bit more aggressive because there still is a bit of the "dieback" present. It is visible only under fluorescent lighting.

I am quite sure there is enough clear for a little more buffing. Right now I am planning to use a Porter Cable PC and foam pads to smooth things out a bit. (I don't want to use my Makita Rotary unless I really have to.) I have only Meguiar's products available in my arsenal....Meguiar's maroon cutting pads, Meguiar's polishing pads, Meguiar's Ultimate Compound and Ultimate Polish. Basically pretty safe stuff and I am in no hurry to get this done...the reason for using the PC rather that the Rotary.

I don't want to do any more sanding because it might make the surface too smooth. My Ram is blessed with considerable factory orange peel.

Any suggestions on using these products.

Oh, I could have pushed for more work to be done by the shop, but I chose not to. I tend to be more cautious than most body techs. If for some reason the paint "goes south" in a year or two, I'll plead ignorance and have it redone.

Again... the dieback is in the clearcoat only.

Originally Posted by tguil

Yep, that's it. The shop owner thinks the temperature in the booth might have been off just bit...sort of funky weather when the painting was done. This is a a "state of the art shop" with well trained techs. The condition is most certainly not bad enough to justify more paintwork. I can only see the "dieback" through my trifocals in just the right light. It actually looks a bit like "micro orange peel" or perhaps an egg shell. (Yeah, I'm an "old guy"...been messin' with detailing for over fifty years.)

Old guy to old guy.....

That's the first time I've heard the term used as well.

Is it possible to post a closeup photo of the defect?

I've got an idea of what you describing and it sounds like a little careful wet-sanding with 3000 on a rubber block should knock off the high spots for polishing. OR just use some compound on the affected area and try to match the rest of the hood..

Thy to avoid sharp edges as the paint is at its thinnest here...

**tguil** · 03-07-2013, 09:40 AM

The condition is so minor that a camera will not pick it up. Not only am I old, I'm a bit "obsessive" too.

**Setec Astronomy** · 03-07-2013, 10:08 AM

Bobby, from what I read this is a solvent trapping phenomenon, so it may not be a "top-down" defect that can be sanded away, if it is further down in the clear...