Mike Phillips
08-24-2016, 07:44 AM
What it means to remove a scratch out of anything... (http://www.autogeekonline.net/forum/ask-mike-phillips-your-detailing-questions/104333-what-means-remove-scratch-out-anything.html)
I wrote this article back in July of 2005 on MeguiarsOnline.com and because I referenced it a number of times in the last few months I've re-written it and updated it to share it here. The original can be found here (http://www.meguiarsonline.com/forums/showthread.php?7228-What-it-means-to-remove-a-scratch-out-of-anything) where you can also see the time date stamp.
We get a lot of questions on our forum and at our classes from people trying to remove scratches out of all kinds of things, for example:
How do you remove a scratch out of;
* Glass?
* Clear plastics like a headlight lens, radio face plate, dash gages, display screens?
* Chrome, like a chrome wheel?
* Paint?
* Interior plastics like a plastic door sill or plastic around the console?
* Stainless steel, like a stainless steel door sill?
* Aluminum?
* Rubber?
* Pebble textured plastic like trim components?
* Leather - leather seats, leather dashes, leather consoles etc.
This article isn't' about the how-to for removing scratches out of the above materials or coatings but about the practical science behind how you remove a scratch or any below surface defect out of any material or surface coating.
Materials: Examples of materials would be plastic, leather, glass, aluminum, stainless steel.
Coatings: Examples of coatings would be the clearcoat layer of paint on your new car, the layer of chrome on your wheels or trim, the layer of black colored plastic over white plastic on exterior car trim pieces.
Read the below statement and think about it for a few minutes...
Some materials and/or surface coatings don't lend themselves well to being abraded with the end-result looking good or looking like the original appearance
In order to remove a scratch out of anything, metal, plastic glass, paint, etc. You must remove material around the scratch until the upper most portions of the surface are level with or equal to the lowest depths of the scratch or defect you're trying to remove.
Does that make sense?
When I say the end result won't look good or look like the original appearance, in the context of abrading the surface, what I mean for example is a lot of cars have a pebble textured plastic door sill where it's common for scratches to build up as people drag their shoes over it as they get into and out of the car.
You could sand the pebble textured surface and LEVEL the scratches but where you sanded will no longer have a pebble texture to it but instead it will be flat. So it won't look good and it certainly won't look like the original appearance.
Make sense? And you can apply this same analogy to most materials or coatings no matter what you rub against them to abrade them to level the surface to make the defects visually disappear.
The below diagram is for paint, however the same idea applies to just about any coating or surface material.
http://archive.meguiarsonline.com/gallery/data/500/2scratchesinpaint.jpg
In essence, you don't really remove a scratch, you remove material around a scratch.
Then the big question becomes...
Is the material or coating workable?
As in,
Can you abrade small particles of the material or surface coating and leave behind an original looking surface.
For example: Some things you can abrade, (remove the scratch), but you can never completely remove all of your abrading marks, thus you can't really fix the problem, all you can do is exchange one set of scratches of a different set of scratches.
The next factor you have to consider or at least understand is;
How thick is the surface coating or material you're working on?
You are limited to what you can do with any material or surface coating. By this we mean there is usually a limit as to how much material you can safely remove before you run into the risk of removing too much coating and exposing the underlying surface or removing so much material that you change the component you're working on in a way that it won't look good and you can't undo the damage.
A great example of how thick or how THIN a coating is would be the paint on your car.
Clearcoats are thin by Mike Phillips (http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/87410-clearcoats-thin-mike-phillips.html)
The factory clearcoat on a new or modern car measures approximately 2 mils thin.
The average post-it not is around 3 mils thin.
http://www.autogeekonline.net/gallery/watermark.php?file=68387
If you just read this far down this article and you just learned how thin the clearcoat paint is on your car, then you just learned how important it is for whoever works on you car's paint be it you as a do-it-yourselfer, or you hire a Detailer, or you let the Dealership wash or detail your car, or you have work done on your car at a body shop, it's important that WHOEVER works on your car's paint KNOW WHAT THEY ARE DOING BECAUSE THEY DON'T HAVE A LOT OF MATERIAL TO WORK WITH.
Make sense?
This is why I always teach people three things,
1. "Use the least aggressive product to get the job done" (http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/28505-use-least-aggressive-product-get-job-done.html)
2. Always do a TEST SPOT (http://www.autogeekonline.net/forum/how-articles/50162-how-do-test-spot.html) before working on the entire car or an entire panel.
3. Never skimp abrasive technology, that is never skimp on compounds, polishes and cleaner/waxes.
Abrasive Technology
These are the product you use to remove defects out of car paint and you always want to use product that use great abrasive technology. Yes... there are products on the market that DON'T use great abrasive technology and while they may remove defects they will leave their own defects behind. Each time you go to remove defects you remove a little paint and the picture above of my fingers holding a post-it note teaches you that the paint on your car is THIN. So don't skimp on compounds, polishes and cleaner/waxes. If you hire someone to work on your car make sure they're using quality products. If you let the dealership work on your car ask them what they're going to do and what they are going to use. And if you take your car to a body shop - well the chances are really good if they do any buffing at all you're going to have holograms in the paint. That's just how that industry goes.
There's a saying on this forum we use often when discussing different members detailing projects and it goes like this,
"Sometimes you don't know what you can so until you try"
It's always a good idea to test your choice of products, applicator materials and application process, (by hand or by machine), to an inconspicuous area. If you cannot make a small area look good with your product, applicator and process, you will not be able to make the entire surface look good.
It's always a good idea to test first and error on the side of caution, versus make a mistake you cannot undo over the entire component or vehicle.
Hope the above makes sense and I hope it helps clear up any confusion over what can be done and what cannot be done in the car detailing world.
:)
I wrote this article back in July of 2005 on MeguiarsOnline.com and because I referenced it a number of times in the last few months I've re-written it and updated it to share it here. The original can be found here (http://www.meguiarsonline.com/forums/showthread.php?7228-What-it-means-to-remove-a-scratch-out-of-anything) where you can also see the time date stamp.
We get a lot of questions on our forum and at our classes from people trying to remove scratches out of all kinds of things, for example:
How do you remove a scratch out of;
* Glass?
* Clear plastics like a headlight lens, radio face plate, dash gages, display screens?
* Chrome, like a chrome wheel?
* Paint?
* Interior plastics like a plastic door sill or plastic around the console?
* Stainless steel, like a stainless steel door sill?
* Aluminum?
* Rubber?
* Pebble textured plastic like trim components?
* Leather - leather seats, leather dashes, leather consoles etc.
This article isn't' about the how-to for removing scratches out of the above materials or coatings but about the practical science behind how you remove a scratch or any below surface defect out of any material or surface coating.
Materials: Examples of materials would be plastic, leather, glass, aluminum, stainless steel.
Coatings: Examples of coatings would be the clearcoat layer of paint on your new car, the layer of chrome on your wheels or trim, the layer of black colored plastic over white plastic on exterior car trim pieces.
Read the below statement and think about it for a few minutes...
Some materials and/or surface coatings don't lend themselves well to being abraded with the end-result looking good or looking like the original appearance
In order to remove a scratch out of anything, metal, plastic glass, paint, etc. You must remove material around the scratch until the upper most portions of the surface are level with or equal to the lowest depths of the scratch or defect you're trying to remove.
Does that make sense?
When I say the end result won't look good or look like the original appearance, in the context of abrading the surface, what I mean for example is a lot of cars have a pebble textured plastic door sill where it's common for scratches to build up as people drag their shoes over it as they get into and out of the car.
You could sand the pebble textured surface and LEVEL the scratches but where you sanded will no longer have a pebble texture to it but instead it will be flat. So it won't look good and it certainly won't look like the original appearance.
Make sense? And you can apply this same analogy to most materials or coatings no matter what you rub against them to abrade them to level the surface to make the defects visually disappear.
The below diagram is for paint, however the same idea applies to just about any coating or surface material.
http://archive.meguiarsonline.com/gallery/data/500/2scratchesinpaint.jpg
In essence, you don't really remove a scratch, you remove material around a scratch.
Then the big question becomes...
Is the material or coating workable?
As in,
Can you abrade small particles of the material or surface coating and leave behind an original looking surface.
For example: Some things you can abrade, (remove the scratch), but you can never completely remove all of your abrading marks, thus you can't really fix the problem, all you can do is exchange one set of scratches of a different set of scratches.
The next factor you have to consider or at least understand is;
How thick is the surface coating or material you're working on?
You are limited to what you can do with any material or surface coating. By this we mean there is usually a limit as to how much material you can safely remove before you run into the risk of removing too much coating and exposing the underlying surface or removing so much material that you change the component you're working on in a way that it won't look good and you can't undo the damage.
A great example of how thick or how THIN a coating is would be the paint on your car.
Clearcoats are thin by Mike Phillips (http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/87410-clearcoats-thin-mike-phillips.html)
The factory clearcoat on a new or modern car measures approximately 2 mils thin.
The average post-it not is around 3 mils thin.
http://www.autogeekonline.net/gallery/watermark.php?file=68387
If you just read this far down this article and you just learned how thin the clearcoat paint is on your car, then you just learned how important it is for whoever works on you car's paint be it you as a do-it-yourselfer, or you hire a Detailer, or you let the Dealership wash or detail your car, or you have work done on your car at a body shop, it's important that WHOEVER works on your car's paint KNOW WHAT THEY ARE DOING BECAUSE THEY DON'T HAVE A LOT OF MATERIAL TO WORK WITH.
Make sense?
This is why I always teach people three things,
1. "Use the least aggressive product to get the job done" (http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/28505-use-least-aggressive-product-get-job-done.html)
2. Always do a TEST SPOT (http://www.autogeekonline.net/forum/how-articles/50162-how-do-test-spot.html) before working on the entire car or an entire panel.
3. Never skimp abrasive technology, that is never skimp on compounds, polishes and cleaner/waxes.
Abrasive Technology
These are the product you use to remove defects out of car paint and you always want to use product that use great abrasive technology. Yes... there are products on the market that DON'T use great abrasive technology and while they may remove defects they will leave their own defects behind. Each time you go to remove defects you remove a little paint and the picture above of my fingers holding a post-it note teaches you that the paint on your car is THIN. So don't skimp on compounds, polishes and cleaner/waxes. If you hire someone to work on your car make sure they're using quality products. If you let the dealership work on your car ask them what they're going to do and what they are going to use. And if you take your car to a body shop - well the chances are really good if they do any buffing at all you're going to have holograms in the paint. That's just how that industry goes.
There's a saying on this forum we use often when discussing different members detailing projects and it goes like this,
"Sometimes you don't know what you can so until you try"
It's always a good idea to test your choice of products, applicator materials and application process, (by hand or by machine), to an inconspicuous area. If you cannot make a small area look good with your product, applicator and process, you will not be able to make the entire surface look good.
It's always a good idea to test first and error on the side of caution, versus make a mistake you cannot undo over the entire component or vehicle.
Hope the above makes sense and I hope it helps clear up any confusion over what can be done and what cannot be done in the car detailing world.
:)