Crosshatch Pattern - Why and When to use a crosshatch pattern to buff paint

Crosshatch Pattern - Why and When to use a crosshatch pattern to buff paint


If you're new to machine polishing you have probably heard someone say,

Use a crosshatch pattern


What do they mean by that? Real simple. When buffing a section of paint move the polisher over the section side-to-side like this,

http://www.autogeekonline.net/galler...22/onepass.jpg



Then after covering that section change directions and move the polisher front-to-back.

http://www.autogeekonline.net/galler...22/twopass.jpg



Then repeat this side-to-side, front-to-back pattern until you have repeated this pattern for a total of around 8 times.



Why 8 times?

Buffing over a section of paint 8 times is just a good rule-of-thumb. You may need to make more section passes to remove deeper defects on harder paints when compounding. And you might only need to make 6 section passes if polishing after the compounding step where all you're trying to do is remove any residual haze after an aggressive compound and/or and aggressive product to maximize gloss and clarity.

So the recommendation for 8 section passes is just a general rule-of-thumb. You would find out how many section passes it takes for the car you're working on by FIRST doing what we call a Test Spot.



Thin body panels
What if the area I'm buffing is not a large section and thus there is not enough room to buff in a crosshatch pattern?

This is normal. For example, if you are buffing the top of a fender where on one side you have an edge and the other side you have a raised body line. This type of panel is too thin to realistically use a crosshatch pattern. For panels like this simply move the polisher back and forth in a linear line. If possible try to overlap these back-and-forth passes, even if just a little.


Buffing in a back-n-forth linear line on a thin body panel

http://www.marine31online.com/galler...nMakita_03.JPG



Test Spot - What is a Test Spot?
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.

Here's my Test Spot on the trunk lid of 1939 Chevy Streetrod. The results from my testing met my expectations for the paint on this car so next I simply REPEATED the process I used for the Test Spot to the rest of the car.

http://www.autogeekonline.net/galler...ss_Car_019.jpg





Section Pass - What is a Section Pass?


The definition of a pass
There are two definitions of the word pass as it relates to machine polishing with any type of machine.


Single Pass
A single pass is just that. It's when you move the polisher from one side of the section you're buffing to the other side of the section you're buffing. That's a single pass.


Section Pass
A section pass is when you move the polisher back and forth, or front to back with enough single overlapping passes to cover the entire section one time. That's a section pass.




Putting it all together
The above are some of the BASIC terms used in the car detailing industry. Or at least used on this forum, my classes and in all my books as I coined some of these terms for our industry.


Sit back and relax - it's all in this video!
If you are truly new to car detailing and specifically machine polishing. Click the link below and watch the video as I show and explain all of the above terms. I also show you exactly how to go about machine buffing out a car. The tools shown in the video is the tried-n-true Porter Cable 7424XP - it is one of the weaker 8mm free spinning random orbital polishers on the market today BUT all the tips and techniques I share in this video WILL APPLY to any other type or brand of random orbital polisher. Both free spinning and gear-driven. Both short stroke and long stroke.

The MOST important thing when it comes to buffing out a car is to always use compounds, polishes and cleaner/waxes that use great abrasive technology because it is the abrasives that are touching the paint first - not the pad, the tool or your technique.

https://www.youtube.com/watch?v=ulWXODgg8V4



First time purchase for a polisher?
And if you're going to purchase a polisher for the first time... take a moment to click the link below and read my article. Besides recommending the Griot's 6" Random Orbital Polisher it has TONS of information that you're going to need to know to get your first time purchase of everything you'll need right the first time. PLUS tons of info on how to machine polish a car.


Here's what you need to get into machine polishing - Recommendations for a beginner by Mike Phillips



:)

Nice. :props:

Great explanation Mike, good points indeed.


Aaryn NZ. :dblthumb2:

Okay - done.


Needed this article for another article. So I pulled it or typed it up out of thin air.



:)

:updated:


Shared here,

Alright folks. I have my TORQ FX10 in hand. Now what?



:)