Circles or Straight Lines?

[TOGWT]

Polish /Wax / Polymer Directional Application:
What makes a scratch visible is the way light reflects from its microscopic peaks and valley’s are two-dimensional and the light reflects from them differently from the rest of the paint surface.

The reasoning behind hand polishing in one direction only is that unlike a machine polisher the pressure applied is not consistent, especially if you polish using circular motions. The inconsistent abraded pattern causes light to reflect unevenly thereby highlighting the abrasions or scratches

Order of product application- hood- roof-trunk from front to back and, where practical, the quarter panels- door panels- and bumpers from top to bottom. Washing, claying and waxing that way has to do with the way light reflects off the body panels and is also less likely to show the surface marring that you will invariably make.



• Polishes- these products contain abrasives and should be applied in straight-line motions (Forget what Mr. Miyagi was teaching the Karate Kid) circular motions will cause circular directional marks (swirl marks) When an abrasive is applied by hand the pressure applied is uneven and the reflected light highlights the peaks and valleys differently.
•Polymer sealant, Glaze or Wax- these products are all non-abrasive so direction of application won’t cause directional marks to the surface.

•Machine application - when you abrade an area with a machine and a foam pad these abrasions form a uniform pattern (the machine /foam pad applies an even and consistent pressure) and light reflects from its surface evenly without any two-dimensional reflectance.

•Optimising light refraction - apply product in ‘direction of airflow’, horizontal surfaces hood to trunk, vertical surfaces front to back. This application technique affects the paints optical properties by optimising the surface light refraction and the reflectivity of the bodylines and contours of the vehicle

[DC08SI]

Originally Posted by TOGWT

Polish /Wax / Polymer Directional Application:
What makes a scratch visible is the way light reflects from its microscopic peaks and valley’s are two-dimensional and the light reflects from them differently from the rest of the paint surface.

The reasoning behind hand polishing in one direction only is that unlike a machine polisher the pressure applied is not consistent, especially if you polish using circular motions. The inconsistent abraded pattern causes light to reflect unevenly thereby highlighting the abrasions or scratches

Order of product application- hood- roof-trunk from front to back and, where practical, the quarter panels- door panels- and bumpers from top to bottom. Washing, claying and waxing that way has to do with the way light reflects off the body panels and is also less likely to show the surface marring that you will invariably make.



• Polishes- these products contain abrasives and should be applied in straight-line motions (Forget what Mr. Miyagi was teaching the Karate Kid) circular motions will cause circular directional marks (swirl marks) When an abrasive is applied by hand the pressure applied is uneven and the reflected light highlights the peaks and valleys differently.
•Polymer sealant, Glaze or Wax- these products are all non-abrasive so direction of application won’t cause directional marks to the surface.

•Machine application - when you abrade an area with a machine and a foam pad these abrasions form a uniform pattern (the machine /foam pad applies an even and consistent pressure) and light reflects from its surface evenly without any two-dimensional reflectance.

•Optimising light refraction - apply product in ‘direction of airflow’, horizontal surfaces hood to trunk, vertical surfaces front to back. This application technique affects the paints optical properties by optimising the surface light refraction and the reflectivity of the bodylines and contours of the vehicle

Great post, thanks for the info! I am starting to bring things together now...

[wytstang]

Listen to TOGWT he's forgot more then most of us know heck if I knew half of what he's forgotten I'd be going places lol.

[ZoranC]

Originally Posted by TOGWT

•Optimising light refraction - apply product in ‘direction of airflow’, horizontal surfaces hood to trunk, vertical surfaces front to back. This application technique affects the paints optical properties by optimising the surface light refraction and the reflectivity of the bodylines and contours of the vehicle

May I ask which laws of physics (optics) would stand behind this?

[Surfer]

I kinda do half circles/circles, works better then straight for me. But I haven't used wax in awhile as I have no time, barely wash the vehicles right now, if I do use anything its AW which is buff on buff off.

[Z06-Goose]

Originally Posted by Al-53

the theory is that straight line application reduces the chance of swirling and also it is suppose to reflect the light better if done in straight line....some sealants even say do in straight lines for the best looks...

the process is...top panels..roof...hood...trunk area do as the wind flows..front to rear...

side panels..do as the rain falls..top to bottom....

AL

I'm with Al. I started to use this method when applying paste wax. With sealants, and liquid waxes, I use circular motion since there is hardly any friction with the finish at all

[Bunky]

What is the source of TOWGT's conclusions? I encourage others who do this for a living to post their real world experiences.

[Al-53]

The theory is..sealants.. waxes do not dry completely flat...it has ridges but in micro sense....so in when light reflects the straight line application reflects better than a circular application...just like paint....do your wall in a circular motion and you will see them...straight line you will not...I know paint is thicker so more definition..but you get the idea....

AL

[Jimmie]

Here is more curve ball to the issue. Swirls are straight line scratches that are reflecting/refracting light in what appear to be swirls. How else can they appear to be so concentric? Just something that I read.
I apply in overlapping circles for coverage.

[TOGWT]

Originally Posted by ZoranC

May I ask which laws of physics (optics) would stand behind this?

Specula Reflection - Such behavior is described by the law of reflection, which states that the direction of incoming light (the incident ray), and the direction of outgoing light reflected (the reflected ray) make the same angle with respect to the surface normal, thus the angle of incidence equals the angle of reflection; this is commonly stated as θi = θr.