Fight or Flight Method for Gaging Surface Temperature

[Mike Phillips]

Fight or Flight Method for Gaging Surface Temperature

The topic of heat comes up often when talking about using a rotary buffer to machine compound or polish paint. For decades now I read comments by people where they state heat is necessary when using a rotary buffer with a compound, or any other abrasive product that uses diminishing abrasives for abrading ability, in order to break the diminishing abrasives down. This is not accurate.

When buffing with a rotary buffer and any type of product that contains diminishing abrasive, including a compounds, paint cleaners, cleaner/polishes and even a cleaner/waxes, what's necessary is pressure over time. Heat is just an unnecessary and unwanted byproduct of the process.

When using a rotary buffer for correction work for even a minute or longer, heat is unavoidable. The smaller the section your work the greater the risk of getting the paint hot. It's normal and okay to get paint warm, (because there's nothing you can do about it), but you don't want to get paint hot and if you do get paint hot then you want to stop buffing in that section and let the paint cool down. So the question is,

How hot it too hot?

Or

What temperature range is consider warm and within a range that's safe to work a rotary buffer?


I don't know any specific temperature ranges recommended by any of the major paint companies to work within or extreme hot temperature ranges to avoid, so here's the common sense approach anyone can use on-the-fly when buffing with a rotary buffer. This is a method I've been using since I started using a rotary buffer in the late 1980's and that I've been teaching in any class that includes using a rotary buffer. It's simple, yet effective and you don't need to purchase any testing tools as you already have the tool you need built-in.

This method works off your hand's sense of touch and your brain's instincts to protect you. I call it the Fight or Flight Method for Gaging Surface Temperature. Not one of my better titles but descriptive to say the least.

The Fight or Flight Method for Gaging Surface Temperature
When using a rotary buffer, periodically check the temperature of the paint by placing the palm of your hand flat on top of a section you just finished buffing, like this,




If the paint feels warm, even close to hot, BUT it's not so hot that you jerk your hand away, then it's in a temperature range that's safe to buff.

If you you place your hand on the paint and your Fight or Flight instinct takes over an you find yourself jerking your hand away from the surface at the speed of light, then the paint is too hot and you should stop buffing that section and allow the paint to cool down.

Kind of caveman but you get the idea. The bigger point is to check the surface temperature of the paint once in a while because you might surprise yourself at how hot you're getting the paint. Because you're in control of the rotary buffer you need pay attention to the surface temperature and this means pausing for a moment to feel the paint.

Different body panel materials, for example steel, aluminum, fiberglass, composite, will heat up at different rates and will either dissipate or hold heat at different rates, so it's a good idea to check each time you work on a different car.

With testing, you can get a feel, (not pun intended), for how long you can buff an average size section and not be getting the paint too hot.

[Steven C]

Awesome tip Mike never had a name for it but I've been doing for years. Love reading your posts they're always very informative &well thought thanks Mike.

[detaildave]

[christian900se]

I've always been curious about this particular issue as to how far I can go. Great job posting this!

Ps. Maybe you might want to add in the difference between the acceptable temperatures for metal body panels and plastic panels? I didn't see it specified but I know your post was applicable to metal panels in terms of safe heat levels.

[Mike Phillips]

Ps. Maybe you might want to add in the difference between the acceptable temperatures for metal body panels and plastic panels?
I didn't see it specified but I know your post was applicable to metal panels in terms of safe heat levels.

On the surface that's a great idea but if we dig a little deeper one thing we want to do when detailing cars for fun or profit is to try to streamline process to make it faster versus take longer as it already takes long enough.


Creating a more complex method would actually be doing something very opposite of what I normally do. Most people want to take something very simple and make it very complicated. I like to keep things real simple so anyone can do it.

On-the-fly
I could do the research for paints, panel materials and then showcase one of the Infrared Temperature Reading Guns and write out a very detailed and complex how-to article or just keep it real simple, easy and fast enough that you can do the checking on-the-fly.


So with the method outlined here you simply feel the paint and if the first thing you think is

Dang! that's hot!

Then quit buffing that section. (simple and uncomplicated). It's not rocket science so I don't want to make it rocket science. If I did I could do all the research and then show a tool like this and we could all increase the amount of time it takes to buff out a car by stopping the work and measuring the surface temp and then looking a a graph on the wall or something like that.


Seriously, you're idea is great but this is one instance where it's just effective in the big picture just to put you hand on the paint and make sure you're not getting the paint too hot. This is ESPECIALLY true if you're working on trying to remove isolated defects where you're buffing and buffing in one small area.


Or, I could have Dwayne bring something like this into the store and write a new how-to article.

Temp Gun

[Lee Yoder]

Mike,
I was thinking of temp guns the whole time I was reading this thread. We use them in the power plant all of the time to check piping, valves, etc. But, you would have to know the specific characterics of the paint and the base materials, and that is beyond the realm of the intent of 'keeping it real'. I like the 'dang, that's hot' approach.

Later,
Lee

[BrOkEn_Dc2]

I have used a temp gauge before out of curiosity. I read an average between 135-150 when buffing in a non-A/C garage during the hot Florida summer.

[Mike Phillips]

Mike,
I was thinking of temp guns the whole time I was reading this thread. We use them in the power plant all of the time to check piping, valves, etc. But, you would have to know the specific characterics of the paint and the base materials, and that is beyond the realm of the intent of 'keeping it real'.

I like the 'dang, that's hot' approach.

Later,
Lee

Sometimes the simple methods works as well as gets the job done.

I have used a temp gauge before out of curiosity.

I read an average between 135-150 when buffing in a non-A/C garage during the hot Florida summer.

The term for getting paint too hot when machine buffing is called,

Destructive Paint Polishing


Jason Rose gave that to me but I always give him credit for the term. I talk about it and the actual temp ranges in the second edition of my how-to book.

[57BORNTORUN]

If this whole paint polishing thing does not work out for you Mike...how about hand modeling like George Costanza on Seinfeld.Dont forget the oven mits and stay away from hot irons.

[hernandez.art13]

I was taught that paint gets hotter on a DA with a smaller backing plate then a rotary with a small backing plate.

Let me try and explain as best as I can.

DA 3" backing plate = gets hotter faster
DA 5.5"+ backing plate = gets hotter slower

Rotary 3" backing plate = gets hotter slower
Rotary 5.5"+ backing plate = gets hotter faster

I think that's how it was explained.

Any thoughts anyone?