Todd@RUPES
Just a regular guy
After experiencing first hand defect removal from both M105 and M95, I was contacted by Kevin Brown (who is much more knowledgable then me when it comes to this paint correction stuff). Kevin then referred a specific question that him and I had discussed to Jason Rose from Meguiars. Jason is a detailing enthusist and a wealth of factual discussion.
I asked his permission to post his response in my M95 thread, but thought that the information (in a world of misinformation) was so valuable and hopefully benefit many of us, that it deserved its own thread.
I feel like I just went to school
Whenever I experience (or hear about) “filling over defects� or “paint-filling�, it is ALWAYS due to one of two things:
(1) The product has in fact covered up defects, or (2) The paint has temporarily swelled (especially fresh paint.)
Filling products:
Many paint care products can do this. And it’s not brand specific. It’s not a brand thing, it’s about what the product is supposed to do and what ingredients it has. Chemists know exactly what ingredients to put in to accomplish this- They know exactly what ingredients to avoid to prevent it. M105 and M95 do not have anything in them intended to fill defects. I was lead on the development team for those two products and I can assure you that it was a high priority (and a top value proposition) to create defect removal products that provide “what you see is what you get� results.
I’m a detailer at heart…down to my core that is all I am…And I find it very frustrating when I work hard to get defects out and discover them coming back later. If we wanted M105 and M95 to fill defects, we know exactly how to do that. But we did not.
Another thing to consider while looking into a “fillingâ€� situation is the use of high tech spray-able polymers or polymer sealants. A paint loaded up with durable polymers will definitely throw off subsequent compound and polish performance. I learned this the hard way…by trying to figure out crazy anomalies in results of product testing going on in 24 countries. These polymers can be arch applied at a car wash, sprayed on by detailers, and/or waxed on by consumers. And some of these products, like Meguiar’s UQD, M135 Synthetic Spray Detailer, or Tech Wax 2.0 or M21 Synthetic Sealant 2.0 can have a lasting impact on a paint finish…to the extent of throwing off the performance of compounds and polishes in a subsequent application. A fun exercise for the curious would be to get a hood with nothing applied to it for at least 6 months (or thoroughly stripped with strong APC) and apply M135 on half the hood. Then buff the whole hood with a compound. You’ll be amazed at the difference in buffing cycle, defect removal, and finish from one side to the other. So in this case, any defects “coming back laterâ€� had less to do with the compound and more to do with what was on the paint first. Filling could be involved, but not in the way you might suspect.
Paint swelling:
Automotive paint is classified as a semi-permeable membrane, like your skin. Some chemicals penetrate in easily, others stay on top. It is also elastic, like your skin. 100% pure petroleum jelly (Vaseline) will actually make your skin thicker by putting oils into tissue pores. It will also make your skin stretch further by making tissue have more tensile strength and elongation (actual technical terms paint experts use to specify elasticity.)
Why is paint this way? Cars are subjected to temperature swings of 40 degrees, sometimes 60 degrees, on a DAILY basis. What happens to metals and other substrates during this temperature fluctuation? They expand and contract (so does your skin). So, paint…Which is the skin over the substrate…Must expand and contract with the substrate. Those of you with paint gauges, I would encourage you to try an experiment. Take a black car…Measure paint thickness on the hood while the car is indoors at temps below 50 degrees. Then, put the car in the sun mid-day at temps above 80 degrees. Wait for an hour. Measure the same spot. You will often have taller paint in the sun (by how much depends on a set of variables; instrument sensitivity, elongation spec of the paint, and humidity, etc). Paint departments in car factories are temperature and humidity controlled for a variety of reasons; one of which is to have consistency while measuring paint thicknesses. If they did not control for temp/humidity, paint thickness would be a moving target.
Here is another experiment. Take a freshly paint car and sand/buff…Two steps of sanding and two steps of polishing. We should have removed a lot of paint, right? Paint thickness should be shorter, right? Not always. I have COUNTLESS times measured taller thicknesses on fresh paint after removing a lot paint. Why? How? Fresh paint is still full of escaping solvents. Buffing heats up paint. Solvents, resins, and other ingredients in paint swell when you heat them up (You know the whole liquid/gas thing that helps bombs work…I’m not a chemist, but I know something is working there.) By measuring this same paint daily for 3 months, you will see that paint thickness has a life of its own.
OK, this is the last experiment I will suggest!
Look at the cracks in your skin on the top of your hand. Take your other hand, thumb and forefinger…Spread the skin stretching it outward. Do this in both directions. What happened? Cracks went away didn’t they? You’ve just demonstrated for yourself what paint can do.
Now, you must know that paint elongation (thus swelling) is a VARIABLE. This means what you experienced on one car does not mean all cars. What you experienced on one BMW does not mean all BMW’s react the same. And especially when you buff on fresh paint…with any product…you can experience varying degrees of paint hardness and thickness on day one vs day four, or 6 months later.
THE POINT OF ALL THIS…What you experience with M105 or M95 (or any liquid) on one car, does not mean all cars.
I hope this is helpful to you.
I asked his permission to post his response in my M95 thread, but thought that the information (in a world of misinformation) was so valuable and hopefully benefit many of us, that it deserved its own thread.
I feel like I just went to school

Whenever I experience (or hear about) “filling over defects� or “paint-filling�, it is ALWAYS due to one of two things:
(1) The product has in fact covered up defects, or (2) The paint has temporarily swelled (especially fresh paint.)
Filling products:
Many paint care products can do this. And it’s not brand specific. It’s not a brand thing, it’s about what the product is supposed to do and what ingredients it has. Chemists know exactly what ingredients to put in to accomplish this- They know exactly what ingredients to avoid to prevent it. M105 and M95 do not have anything in them intended to fill defects. I was lead on the development team for those two products and I can assure you that it was a high priority (and a top value proposition) to create defect removal products that provide “what you see is what you get� results.
I’m a detailer at heart…down to my core that is all I am…And I find it very frustrating when I work hard to get defects out and discover them coming back later. If we wanted M105 and M95 to fill defects, we know exactly how to do that. But we did not.
Another thing to consider while looking into a “fillingâ€� situation is the use of high tech spray-able polymers or polymer sealants. A paint loaded up with durable polymers will definitely throw off subsequent compound and polish performance. I learned this the hard way…by trying to figure out crazy anomalies in results of product testing going on in 24 countries. These polymers can be arch applied at a car wash, sprayed on by detailers, and/or waxed on by consumers. And some of these products, like Meguiar’s UQD, M135 Synthetic Spray Detailer, or Tech Wax 2.0 or M21 Synthetic Sealant 2.0 can have a lasting impact on a paint finish…to the extent of throwing off the performance of compounds and polishes in a subsequent application. A fun exercise for the curious would be to get a hood with nothing applied to it for at least 6 months (or thoroughly stripped with strong APC) and apply M135 on half the hood. Then buff the whole hood with a compound. You’ll be amazed at the difference in buffing cycle, defect removal, and finish from one side to the other. So in this case, any defects “coming back laterâ€� had less to do with the compound and more to do with what was on the paint first. Filling could be involved, but not in the way you might suspect.
Paint swelling:
Automotive paint is classified as a semi-permeable membrane, like your skin. Some chemicals penetrate in easily, others stay on top. It is also elastic, like your skin. 100% pure petroleum jelly (Vaseline) will actually make your skin thicker by putting oils into tissue pores. It will also make your skin stretch further by making tissue have more tensile strength and elongation (actual technical terms paint experts use to specify elasticity.)
Why is paint this way? Cars are subjected to temperature swings of 40 degrees, sometimes 60 degrees, on a DAILY basis. What happens to metals and other substrates during this temperature fluctuation? They expand and contract (so does your skin). So, paint…Which is the skin over the substrate…Must expand and contract with the substrate. Those of you with paint gauges, I would encourage you to try an experiment. Take a black car…Measure paint thickness on the hood while the car is indoors at temps below 50 degrees. Then, put the car in the sun mid-day at temps above 80 degrees. Wait for an hour. Measure the same spot. You will often have taller paint in the sun (by how much depends on a set of variables; instrument sensitivity, elongation spec of the paint, and humidity, etc). Paint departments in car factories are temperature and humidity controlled for a variety of reasons; one of which is to have consistency while measuring paint thicknesses. If they did not control for temp/humidity, paint thickness would be a moving target.
Here is another experiment. Take a freshly paint car and sand/buff…Two steps of sanding and two steps of polishing. We should have removed a lot of paint, right? Paint thickness should be shorter, right? Not always. I have COUNTLESS times measured taller thicknesses on fresh paint after removing a lot paint. Why? How? Fresh paint is still full of escaping solvents. Buffing heats up paint. Solvents, resins, and other ingredients in paint swell when you heat them up (You know the whole liquid/gas thing that helps bombs work…I’m not a chemist, but I know something is working there.) By measuring this same paint daily for 3 months, you will see that paint thickness has a life of its own.
OK, this is the last experiment I will suggest!
Look at the cracks in your skin on the top of your hand. Take your other hand, thumb and forefinger…Spread the skin stretching it outward. Do this in both directions. What happened? Cracks went away didn’t they? You’ve just demonstrated for yourself what paint can do.
Now, you must know that paint elongation (thus swelling) is a VARIABLE. This means what you experienced on one car does not mean all cars. What you experienced on one BMW does not mean all BMW’s react the same. And especially when you buff on fresh paint…with any product…you can experience varying degrees of paint hardness and thickness on day one vs day four, or 6 months later.
THE POINT OF ALL THIS…What you experience with M105 or M95 (or any liquid) on one car, does not mean all cars.
I hope this is helpful to you.