Ceramic Clear Coat on Bumper Cover?
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Ceramic Clear Coat on Bumper Cover?
Is it correct for the ultra hard ceramic clear coat, as applied on the body panels, to be used for the refinishing of a bumper cover? I was under the impression that the bumper required a flexible formula. I can't find any information on the PPG website.
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From: Ponte Vedra Beach FL/ Hampstead, London, England
'84 380 SL/ '02 XK8
Flex additive - plastics bumper covers, spoilers, etc contain plasticizers (softeners) to help them maintain flexibility so that they can respond to temperature changes. Most paint system manufacturers recommend flex additives in some part of the polyurethane re-finish process. However, the recommendations depend upon the specific products the refinisher employs in their paint process. Some require flex additive in undercoats and topcoats, some in clear coats alone, some recommend a combination of methods. Both OEM and aftermarket polyurethane bumpers and mouldings have instructions stating “when painting plastic parts ensure that a flex additive is in the paint” You should also use an adhesive promoter on plastic parts.
Check the Product Sheet sometimes called "P" sheets, these pages tell you what a specific product is designed to do and how to do it.These are simply a listing from the manufacturer of the paint to tell the paint technician what ratio's of what to mix the paint with, the required gun setup and air pressure needed to apply the paint, how long till it's dry and how to dry it (forced air, infrared, or air) and how to finish it out.
Check the Product Sheet sometimes called "P" sheets, these pages tell you what a specific product is designed to do and how to do it.These are simply a listing from the manufacturer of the paint to tell the paint technician what ratio's of what to mix the paint with, the required gun setup and air pressure needed to apply the paint, how long till it's dry and how to dry it (forced air, infrared, or air) and how to finish it out.
Last edited by TOGWT; Dec 19, 2009 at 09:11 AM.
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I'm not sure if the ceramic paint is used on the bumpers. Reason being, anytime I detail a Ferrari F430 or a MB, late model, the bumper has a different color than the rest of the car. This is usually due to the body shell being painted at a different time than the secondary panels such as bumpers and gas door. Take a picture of your car with a flash...sometime you'll see this color variance..especially on a black car.
Last edited by MoeMistry; Dec 19, 2009 at 10:57 AM.
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97 sl320
Flex additive - plastics bumper covers, spoilers, etc contain plasticizers (softeners) to help them maintain flexibility so that they can respond to temperature changes. Most paint system manufacturers recommend flex additives in some part of the polyurethane re-finish process. However, the recommendations depend upon the specific products the refinisher employs in their paint process. Some require flex additive in undercoats and topcoats, some in clear coats alone, some recommend a combination of methods. Both OEM and aftermarket polyurethane bumpers and mouldings have instructions stating “when painting plastic parts ensure that a flex additive is in the paint” You should also use an adhesive promoter on plastic parts.
Check the Product Sheet sometimes called "P" sheets, these pages tell you what a specific product is designed to do and how to do it.These are simply a listing from the manufacturer of the paint to tell the paint technician what ratio's of what to mix the paint with, the required gun setup and air pressure needed to apply the paint, how long till it's dry and how to dry it (forced air, infrared, or air) and how to finish it out.
Check the Product Sheet sometimes called "P" sheets, these pages tell you what a specific product is designed to do and how to do it.These are simply a listing from the manufacturer of the paint to tell the paint technician what ratio's of what to mix the paint with, the required gun setup and air pressure needed to apply the paint, how long till it's dry and how to dry it (forced air, infrared, or air) and how to finish it out.
https://buyat.ppg.com/refinishProduc...a-83f0ca6b6a63
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I'm not sure if the ceramic paint is used on the bumpers. Reason being, anytime I detail a Ferrari F430 or a MB, late model, the bumper has a different color than the rest of the car. This is usually due to the body shell being painted at a different time than the secondary panels such as bumpers and gas door. Take a picture of your car with a flash...sometime you'll see this color variance..especially on a black car.
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From: Ponte Vedra Beach FL/ Hampstead, London, England
'84 380 SL/ '02 XK8
Difference in Colour between Metal and Polyurethane bumper covers
Polyurethane bumper covers will always change colour especially in metallic colours. The plastic has a static charge and the metallic paint will settle different than on the sheet metal parts, causing pigment floatation that will shift the colour darker or lighter.
The other reason is surface temperature, if the sheet metal is colder, the bumper will look lighter, if the sheet metal is hotter than the bumper, and the colour on the bumper will look darker. The third reason is flex additive. If the Clearcoat is applied on the bumper with a flex additive, it will shift the colour slightly.
Polyurethane bumper covers will always change colour especially in metallic colours. The plastic has a static charge and the metallic paint will settle different than on the sheet metal parts, causing pigment floatation that will shift the colour darker or lighter.
The other reason is surface temperature, if the sheet metal is colder, the bumper will look lighter, if the sheet metal is hotter than the bumper, and the colour on the bumper will look darker. The third reason is flex additive. If the Clearcoat is applied on the bumper with a flex additive, it will shift the colour slightly.
An extract from one of a series of unbiased “Detailing Technical Papers” © TOGWT ™ Ltd Copyright 2002-2009, all rights reserved.
Last edited by TOGWT; Dec 20, 2009 at 06:40 AM.
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From: Ponte Vedra Beach FL/ Hampstead, London, England
'84 380 SL/ '02 XK8
Automotive paint is classified as a semi-permeable membrane that has tensile strength and elongation (or elasticity) to enable it to move along with the metal as it expands /contracts due to environmental temperature fluctuations. Polyurethane is a very elastomeric material and moves a lot more than metal
If the paint doesn't 'move' in unison with its substrate it will crack and / or delaminate
If the paint doesn't 'move' in unison with its substrate it will crack and / or delaminate
Last edited by TOGWT; Dec 20, 2009 at 09:03 AM.
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Automotive paint is classified as a semi-permeable membrane that has tensile strength and elongation (or elasticity) to enable it to move along with the metal or polyurethane as it expands /contracts due to environmental temperature fluctuations
If the paint doesn't 'move' in unison with its substrate it will crack and / or delaminate
If the paint doesn't 'move' in unison with its substrate it will crack and / or delaminate
Super Member
Joined: Nov 2003
Posts: 880
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From: Ponte Vedra Beach FL/ Hampstead, London, England
'84 380 SL/ '02 XK8
