Sunday, 3 April 2016

Finessing (Jeweling) Auto Paint

Finessing (Jeweling)

[: this process is given various names- Burnishing, Finessing, Jewelling and Finite paint finishing]

Around 1950 body shops would call it jeweling because they would have to re-buff single stage paint's a week or two after hand over to the client. After a curing process they would have the customer bring the car back and finely burnish the surface with a finish polish that had almost no abrasive abilities and a soft wool pad, this step was referred to as ’jeweling’ to bring out a deep lustre in the paint surface.

Most of us associate machine polishing with removing swirls, scratches and water spots but show car owners, Concours d’élégance participants, detailers and paint renovation paint technicians have long known that all paint finishes, even brand new finishes, can be improved by a final paint burnishing, increasing maximum gloss by reducing microscopic abrasion scratches on the paint's surface, which will increase the gloss of the paint. This process is usually reserved for those who can appreciate the extra effort, and simply want their cars to look their absolute best regardless of cost

Finessing a paint surface is a process of reducing applied pressure and machine speed in combination with a longer polishing time. It is really effective with a rotary polisher and a diminishing abrasive. Be cognizant that excessive pressure will make the pad / polish combination more aggressive, this has the effect of increasing kinetic energy (friction heat) which may result in a strikethrough

Before using this optional step, the paint surface should be scratch-free, level and any holograms are removed. If the surface is polished ’flat’ it will reflect light evenly (as opposed to refracting it at high and low spots) which will increase the overall reflective optics of the paint. Once this has been accomplished the paint surface can be further finessed by using a non-abrasive ultra-soft pad and a diminishing polish combination. It can sometimes take up to four hours or more finessing a paint finish if it is felt that a higher gloss is obtainable.

Typically, the final step in surface polishing; using a finishing polish (Menzerna Super Finish Plus) in tandem with a pad that has no abrasive abilities (LC CCS Gold (100 PPI) Finishing foam). By using little pressure at the beginning of the pass to help fracture the abrasives since the pad isn't providing abrasion and an ultra-fine finishing polish, for the removal of any microscopic pad abrasion, which also reduces the chance of holograms 

If the polish runs out of surface lubrication add Gloss, It EVP Pad Prime is high-grade lubricating oil that greatly extends machine polishing times. 

Rotary Polisheruse slow linear movements, machine passes in single direction using medium pressure. Use a non-aggressive foam pad (LC Gold 100 PPI) and start at 1500, 1200 and then reduce speed to 1000 RPM, adding a tiny bead of polish and then finally finish at 600 RPM, using moderate constant pressure. until the diminishing abrasive goes clear (somewhat similar to Vaseline®) and then make few passes at 800 / 900 RPM using little to no pressure.
By working the abrasives, so that only the finest particulates remain, these micro-fine abrasives will provide the highest obtainable gloss, without leaving any micro-marring of the paint surface.
Larger diameter pads can be beneficial for final polishing, since they can be used longer before they load up with buffing residue. This can be the difference between a pristine finish, and one that is mildly marred with ultra-fine hazing.
 Random Orbital Polisher - use a moderately non aggressive foam pad (LC White) and firm constant pressure, set speed at about 5000 OPM (Flex 3401 using speed setting 3) until polish breaks down then reduce speed to approx. 3500 OPM and work until refined.

Another technique when using a rotary by having your pads off- centre for an orbital style spin does work well at stopping holograms and should only be used with the jeweling process once the polish has broken down, or by using a non-diminishing polish.

Using water

·         Water – distilled water in a fine nozzle spray bottle
·         Lubricant -Prime the foam pad with Dodo Juice Born Slippy
·         Foam pad – soft finishing foam with a med stiff baking plate
·         Speed – slow arm liner movement and machine speed (need to experiment)

1.      Spray a panel until distilled water just starts to run
2.      Prime a soft finishing foam / a med stiff baking plate with Dodo Juice Born Slippy
3.      Use slow arm and machine speed (need to experiment)

This method also works for very soft paint, you will need to experiment with machine and arm liner movement

I hope the above article was informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire. Questions and/ or constructive comments are always appreciated

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