How To Do a Test Spot

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How To Do a Test Spot


A Test Spot
TestSpot03.jpg



A Test Spot is where you take the products, pads, tools and your best technique and buff one small section, usually on a horizontal panel, to test out these things to see if they'll create the results you want, hope for and dream about in some cases.

If your choice of products, pads, tools and technique works to remove the defects and restore the finish to your expectations, then theoretically you should be able to duplicate the same process to the rest of the vehicle and create the same results.

If your choice of products, pads, tools and your technique doesn't create the results you want, hope for and dream about then you can come to the forum and post what you're seeing and we'll do our best to help you tweak your technique, substitute different products, pads and/or tools to see you through to success.


Tape Line
It helps to place a piece of painter's tape on a horizontal surface, usually the hood or trunk lid but if you want to be more discreet you can use the roof. Then only work on one side of the tape line as this will make it very easy for you to see visual changes due to the distinct demarcation line between before and after results.


Tape-line using 3M Green Painter's Tape
TapeLine02.jpg



Before and after results along the demarcation line
FlexVideo005.jpg



Test Spot performed by Nick Rutter @ Autogeek on a severely oxidized 2006 GMC Canyon
Here's a series of pictures taken by my co-worker Nick from a severely neglected truck he helped another co-worker Jason to buff out. For this project Nicked performed a Test Spot and the pictures really tell the story of what a Test Spot would look like that I've created this article using these pictures and Nick's permission.

The project vehicle is a severely neglected 2006 GMC Canyon with a heavily oxidized clear coat finish. In this case Nick used a one-step cleaner/wax applied by machine but you would buff the paint in the same way with whatever "system" you were planning on using.

If using a multiple step approach then you would use all the products and do all the steps to your Test Spot because this would be what you would do to the entire vehicle if the results from your Test Spot are good and you want to see what the true end-results are going to be. You can if you want skip applying the LSP or Last Step Product if you're happy with the last prep step as in most cases the application of your LSP will simply either make the paint look even better or maintain the results you've created.



Test Spot
test-spot-redone.jpg



Hood Competed
TestSpot04.jpg



Truck completed
TestSpot06.jpg


TestSpot07.jpg


See the original write-up for this project here,

How To: Maximize Time with a Cleaner Wax/AIO


Test every detailing project that's new to you
If you've never worked on the paint on the project you're currently detailing, the before you buff out the entire car, take a moment to do a Test Spot.

I do a Test Spot on ever car I work on as this give me an idea of,

  • How the paint reacts to machine polishing
  • How the products and pads are working on this specific type of paint
  • A feel for if the paint is hard or soft or somewhere in-between
  • A very good idea as to how the paint will and thus how the vehicle will look after the project is finished.
Plus, if you're buffing out the car professionally you can share with your customer how awesome they're car is going to look after you get through with it.


Here's the results from some of the Test Spots we've done to some of the recent projects cars here at AGO


1959 Chevrolet El Camino - Extreme Makeover - Modeled by Christina

1959ElCamino008.jpg


1959ElCamino084.jpg





Live Broadcast Video - 1965 Plymouth Valiant - Extreme Makeover



Before
1965Plymouth013.jpg



Test Spot
1965Plymouth025.jpg



After
1965Plymouth078.jpg




Wetsanding Test Spot
Even if you're going to wetsand or dampsand a vehicle it's just as important to do a Test Spot by sanding a section of paint and then testing to see what it's going to take to remove 100% of your sanding marks.


Test Spot
MorePeopleMoreBuffers003.jpg



Hood compounded
MorePeopleMoreBuffers004.jpg



After
jaysk508.jpg





Test, test, test...
Test out the products you're planning on using over the entire vehicle to one small area first. Make sure you're getting the results you want, hope for and dream about before buffing out the entire project.


:)
 
Top notch info as usual. I'm new to detailing for profit, and will "profit" from this info!
 
Another AMAZING article, Mike do you ever do detailing get togethers In the west?


Sent from my iPhone using AG Online
 
Another AMAZING article, Mike do you ever do detailing get togethers In the west?

I did when I lived in SoCal, we called them Detailing 101 and Advanced Detailing 102 and TNOG's or Thursday Night Open Garage all at Meguiar's Corporate Headquarters in Irvine, Californial. Did them from 2002 to 2009 then came to Autogeek.


Fantastic info Mike! Thank you!

Thank you.

Been teaching people to do a Test Spot officially since around 1993 when I started recommending it on the Usenet Newsgroups in rec.autos.misc

I think I document it here,

Test Spot - The story behind the story...



:D
 
I do a Test Spot on every car I work on unless I've previously worked on it and already have a feel for how the paint buffs. No exceptions.


Here's a 2006 Mosler I buffed out for Corvette Mike back in 2006, somewhere I have all the before and after pictures from the project but the only pictures I ever processed and put on the Internet were these 5 and they were to show the Test Spot.


If you look at the top of the driver's side fender you can see where I did my test spot after arriving to Corvette Mike's shop and setting up for the day.
MoslerBuffedbyMikePhillips003.jpg




You don't have to tape-off a perfect square and in fact this will just use up precious time. I did this for the picture but to also show all the employees at the shop where I did the work the difference between before and after.

MoslerBuffedbyMikePhillips001.jpg



I had to have a few of the mechanics at Mike's shop help me push the car out into the sun to get this sun shot. The sun was still low in the sky so it was hard to get it on the section I actually worked on. To get this shot I was actually leaning way over on the car shooting away from the car in order to get the sun's reflection as you see it in the lower, right hand corner. Even so you can see the paint was completely filled with swirls.

MoslerBuffedbyMikePhillips002.jpg




I buffed out the entire car including rubbing out all of the louvers by hand using ScratchX. In this picture that's a machine applied coat of NXT I believe.
MoslerBuffedbyMikePhillips004.jpg



Here's the finished work...
MoslerBuffedbyMikePhillips005.jpg



The paint on this car was horrible in two ways.

1. It was completely filled with swirls and scratches.

2. The paint was incredibly soft and would scratch very easily. This is why it was filled with swirls and scratches, (probably from normal washing and wiping).
I found out the paint was soft and scratched easily by doing my test spot.

If you've never worked on the car in front of you, before you buff out the entire car with your first choice of pad and product, first do a Test Spot. Dial-in a process that works and once you've proven it works in a small section then all you have to do is simply duplicate the same proven process to the rest of the car and theoretically you should get the same results over the rest of the car.

It should only take you a few minutes to do your Test Spot and it can save you a lot of time and heartache.


:)
 
I'm hoping to start my car this weekend and had a test spot question. I have some bad scratches in my car.
1) Should I start somewhere other than the scratched area since the whole car is not scratched as much as that specific area?
2) I have 105 300 301 looking at picking up some 205 tomorrow. Should I start with the 105 for the test spot or should I just try the MF pads and the 300?
I have the Megs MF pads 5.5 & 3"
I also several colors of the lake country foam pads and a new porter cable xp. I have a Dodge Caliber if that makes a difference. Thanks for everyones help in getting this far. Can't wait to get started.
 
I'm hoping to start my car this weekend and had a test spot question. I have some bad scratches in my car.
1) Should I start somewhere other than the scratched area since the whole car is not scratched as much as that specific area?

2) I have 105 300 301 looking at picking up some 205 tomorrow. Should I start with the 105 for the test spot or should I just try the MF pads and the 300?

Do a Test Spot for each of the two types of areas.

Chances are good you're going to have to use a compound for the worst area and compound for the areas that are not so bad and that's because modern clear coats are pretty hard.

Also, M105 and D300 are SMAT product so you can stop at any point during the buffing cycle. With DAT product you're supposed to work the products till the diminishing abrasives have fully broken down, the subtle difference is with SMAT you can stop abrading paint when the defects are gone, with DAT it's possible the defects could be removed but you still need to buff to make sure the diminishing abrasives are not leaving their own scratches behind.

(Deep thoughts, deeper than most people care to get)

The M105 is more aggressive than the D300 so you can try the D300 first and if that isn't getting the job done then switch to the M105, both are very very good compounds.


I have the Megs MF pads 5.5 & 3"
I also several colors of the lake country foam pads and a new porter cable xp. I have a Dodge Caliber if that makes a difference. Thanks for everyones help in getting this far. Can't wait to get started.


Great questions!

Key thing is to do some testing and make sure you're seeing the results you want and expect before buffing out the entire car. If you're not seeing the results you want then start a "new thread" to explain what's happening and our forum community will help you to tweak your technique and see you through to success.


Read this BEFORE starting, then you'll know what not to do and what to do from the very start.


DA Polisher Trouble Shooting Guide



:xyxthumbs:
 
***Bump***


Bump for anyone new to machine polishing...

I've been buffing out cars all my life and I ALWAYS do a Test Spot before buffing out any car I have never buffed out previously.

Here's an example from just this last weekend...

See the tape on the front, center of the hood? That's from doing a Test Spot...


New Menzerna FG 400 - One-Step Show Car Makeover


Test Spot = Menzerna FG 400 with the Lake Country 6.5" Hybrid White Polishing Pads on the Flex 3401
I did a Test Spot using a tape-line on the front of the hood and then inspected using my Brinkmann Swirl Finder Light and the results were a clear, high gloss finish that was silky smooth to the touch and all swirls, scratches, water spots and oxidation was removed. After confirming the combination of the Menzerna FG 400 with the Lake Country 6.5" Hybrid White Polishing Pads on the Flex 3401 on speed 6 was giving me the results I wanted I proceeded to buff out the entire car using this combination.

1957_Belair_Mike_Phillips_003.jpg




Finished...

1957_Belair_Mike_Phillips_041.jpg





:xyxthumbs:
 
Just wrote a new article to answer a common question and sometimes problem when doing a Test Spot...

The LINE ---> How to avoid the line!



Something I've been meaning to write about but it's always just another item on my to-do list is how to AVOID the LINE when doing a Test Spot using a strip of painter's tape.

That is the line that separates the before and after results the YOU use to inspect and gauge your progress and results.

This line...

FlexVideo005.jpg




After using a strip of painter's tape for your test spot like this...

How To Do a Test Spot
(and why it's so important)


TapeLine02.jpg



test-spot-redone.jpg



Answer coming up...


:)
 
Here's the follow up...


Question: How to avoid the line!


Answer: Anytime you're doing a test spot, if it's just you're own car or even a customer's car, then buff to the side of the line, not directly on top of the line.


Why?

Because sometimes you can remove enough paint to actually leave a line in the paint that can be hard to buff out.

When I do these types of things for articles I'm trying to create a DRAMATIC "Before & After" picture showing the before and after results with a strong demarcation line.

Unless you "want" or "need" the picture then just buff close to the tape line, not directly on top of the tape line and you'll avoid creating a physical level difference in the paint that shows up as an actual "line" in the paint. (that can sometimes be hard to buff out).


Make sense?


:)
 
So if you do a test spot and conclude it needs more work, do you make a second test spot or continue working the first spot?
 
So if you do a test spot and conclude it needs more work, do you make a second test spot or continue working the first spot?


Great question! :xyxthumbs:

The answer is you do a test spot in a new section of un-touched or un-buffed paint.

Doing a second test spot in the same area will give you skewed results since you've already altered the paint in that spot with the products you tested.



:)
 
Beginner question here:

I will be using a DA for the first time to remove moderate light to moderate swirls. I bought a 7424XP, orange and white LC flat pads, and Meguiars UC and UP. I know that we should always use the least aggressive method.

For my test spot I am thinking of starting with UP on a white pad. It this does not remove the swirls, then do a second (separate, as mentioned above) test spot with UC and an orange pad, followed by the UP/white pad combo.

Is this the right way to approach the situation?
 
Beginner question here:

I will be using a DA for the first time to remove moderate light to moderate swirls. I bought a 7424XP, orange and white LC flat pads, and Meguiars UC and UP. I know that we should always use the least aggressive method.

For my test spot I am thinking of starting with UP on a white pad. It this does not remove the swirls, then do a second (separate, as mentioned above) test spot with UC and an orange pad, followed by the UP/white pad combo.

Is this the right way to approach the situation?


Yes but depending on your paint and what results you want to achieve, ultimate polish wont do much as far removing the swirls (depending on how bad it is) its very light in cut just make sure you do an alcohol wipedown or carpro eraser to inspect the true results.
 
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