UMR = Uniform Material Removal - Removing the same amount of paint when doing correction work for a uniform appearance

[Mike Phillips]

UMR = Uniform Material Removal - Removing the same amount of paint when doing correction work for a uniform appearance


Anytime you're buffing out a car and doing correction work with a,

Compound
Polish
Cleaner/Wax

You want to divide larger panels up into smaller sections and then buff each section until you have removed the below surface defects to your satisfaction. After you finish buffing one section of paint, move onto the next section of paint, (on that panel), but be sure in your buffing pattern, (section passes), to overlap a little into the previous section so you have uniform material removal over the entire panel.

This will ensure a uniform appearance at the end of the process, when you wipe of the wax, the sealant or the coating.

If you buff out a panel section by section but do not overlap your buffing process of the new section a little into the previous section it's possible to have sections with zero swirls and scratches but then see faint swirls and scratches in the areas between your sections that did not receive adequate buffing.

When buffing out a car to remove defects you cannot buff out ENTIRE panels at one time. For example, even with a rotary buffer you cannot buff out an entire hood at one time. Normally you would divide the hood up into 2 or more sections, (for a rotary buffer, not an orbital. An orbital would require more smaller sections as they are not as powerful as a rotary buffer for removing paint).

Because you have to divide larger panels into sections, in order to create a uniform appearance over the entire surface, that is the same level of correction for every square inch of paint, you need to overlap each new section a little into the previsou section so that you remove a uniform amount of material over the entire surface.

Good UMR when buffing out a panel is how you end up with uniform looking results after you make the final wipe of your LSP and then say,

It is finished


Make sense?


UMR = Uniform Material Removal


And of course, this is one of the thousands of topics I cover in all my classes.

[Mike Phillips]

***Placeholder***


I have two very special cars coming to Autogeek that I'll use to take the pictures for this article to show the concept of UMR

[Mike@DedicatedPerfection]

Make sense?


UMR = Uniform Material Removal

Makes perfect sense.

Just as you want to make sure you have uniform even coverage when you apply a wax, sealant, or coating you want the same thing going on when buffing out the paint.

Thanks for sharing

[PaulMys]

Great post, Mike.

I actually have to divide the hood on my Ram into 6 sections while correcting. Lol

[2black1s]

Great topic Mike and I completely agree!

But I'd also point out the other side of the coin. And that is that carelessly overlapping can result in additional and unnecessary paint removal in the overlap area.

If you polish a 2 x 2 section and the do another adjacent 2 x 2 section and overlap into the first section by say 6 inches, then you have removed twice as much paint in the 6 inch overlap area, unless you make the necessary adjustments to your process... this is where a real feel for what you're doing and attention-to-detail are very important.

There is some finesse in order in the process.

[silverfox]

I think if people could see the paint under a microscope after polishing they'd be sick. Just imagine the Rocky Mountains. Not changing out pads enough, too much or too little overlap, speed and arm speed differences, user fatigue, etc ...all add up to the Rocky Mountain highs and lows. We think we are polishing paint to perfection. Far from it.

[Mike Phillips]

I think if people could see the paint under a microscope after polishing they'd be sick. Just imagine the Rocky Mountains.

Not changing out pads enough, too much or too little overlap, speed and arm speed differences, user fatigue, etc ...all add up to the Rocky Mountain highs and lows.

We think we are polishing paint to perfection. Far from it.

I agree.


Luckily... most of us don't own the kind of microscope need to look at our car's paint up close or some of us would probably go crazy.


This is where I like to put the focus on the BIG PICTURE and in this context, use great product, the right pads, the right tools and your best technique and yes, changing out pads often and then when you make the final wipe the paint is going to look great to your eyes and leave the microscopes to Amy Farris Fowler on Big Bang.