Monday 11 May 2015

Repairing / Renovation of Scratched or Curbed Wheels




Aluminium corrosion

Aluminium alloys are alloys in which aluminium is the predominant metal. The highly reactive nature of aluminium metal is normally masked by the protective oxide film (White rust), which readily forms in moist air and renders the metal kinetically stable. Galvanic corrosion can occur when an aluminium alloy is placed in electrical contact with other metals with a more negative corrosion potential than aluminium.

·         Thoroughly clean the affected surfaces of all soil and grease residues with a d-limonene (citrus) based solvent cleaner (P21S® Total Auto Wash) prior to processing. 

·         Brush it down with a wire brush to get rid of all the powder.
·         Clean the surface with PrepSol and then sand any scratched or damaged areas with Norton 3X Sandpaper (p-graded aluminium oxide grain,) 60, 80 or 100 grit sand paper, sand wet or dry with a rubber sanding block.
·         Use a tack rag and wipe the area, using a light pressure
·         Then treat with etch primer, maybe two or more coats.
·         Follow with ordinary primer and top coat.

Be cognizant that if aluminium becomes badly corroded they require an acid dip bath and the polishing

Repairing a Damaged Polished Aluminium Lip

Dremel 3000 Variable Speed Rotary Tool, plus accessories-  kit # 697-- #952 CONE shaped Aluminum Oxide Grinding Stone and - #413 Sanding Discs 240 GRIT
1.        Using the Dremel on its lowest setting with the (#952) Cone shaped stone and grind down the burrs to as near smooth as you can.
2.        Change attachments to the (#413) Sanding discs and smooth the surfaces
3.        Start by using 800 grit finishing paper and then work through 1000, 1500 and finally 2500.
4.        Using #0000 synthetic steel wool to bring back the shine
5.        Finally finish polishing with OPT Optimum Metal Polish
6.        Use a clear polymer  protection (OPT Optimum Opti-Coat)
Repairing Scratched or Curbed Wheels
Damage to your wheels can come from: curb damage, wheel weight scratches, low acid spray, lug nut impact wrench, auto accident, and road salt, which leads to oxidation. These blemishes can ruin the appearance of your car; refurbishment can help retain its value.
Replacement costs for an alloy wheel can cost hundreds of dollars + 3-4 days without the vehicle) but the restoration of your scuffed alloys and scraped wheel rims makes your whole car look pristine again
          Wheel Collision Centerhttp//:www.wheelcollision.com/
          Wheels America  8004-Fix-Rim – Powder coat Finish -  http://www.wheelsamerica.com
          Mobile Wheel Repair (US, UK) - http://www.mobilewheelrepair.com/
          Wheel Repair UK - http://www.thewheelspecialist.co.uk/...ce_details.php.
Be cognizant that serious damage to a wheel may affect the vehicle’s alignment and subsequent steering, always check for structural damage (i.e. surface cracks) or deformed rims, which should always be replaced. Shop cosmetic / appearance wheel repair- approx. $100 –150 per wheel, usually 48 hours (dependent upon geographical area)

These procedures are for aesthetic and slight damage only

Taking the wheel(s) off makes it far easier to work on and much more comfortable than stooping down

Small Scuff Repairs (Alloy Wheels)

Time: 4 – 6 hours per wheel for a complete wheel-off repair and repaint renovation. Materials-2-17 oz. Wurth Clean-Solve, 2-10.2 oz. 1Z Einszett Spray Paint Primer "Haft-Grund", 2-13.5 oz. 1Z Einszett Silver ( will match Titanium Silver) Wheel Spray Paint, 2- 13.5 oz. Wurth High Gloss Clear Lacquer, 14 oz. Bondo®  (approx. total 90 USD)

See also Personal Protective Equipment (PPE)
          Remove the damaged wheel from vehicle.
          Deflate the tyre by unscrewing cap and pushing in valve, once the tyre is flat push the tyre wall down (gently) by standing on it, and then  tuck masking tape underneath the wheel rim, working your way around slowly

          Dremel Tool (with variable speed) accessory kit # 697-06 and #952 CONE shaped Aluminum Oxide Grinding Stone.  Use on its lowest speed (5000 RPM) and grind down the burrs, they can then be made perfectly smooth by using finishing paper and a sanding block

          Molecular Tech Coatings Inc., EFS-2500 aircraft paint stripper is environment friendly. It can get easily decomposed and is also non-toxic as well. In terms of chemical composition, there is no methylene chloride, no carbonic acid, and no formic acid present in the paint stripper. Hence, it is perfectly safe to use.
          Clean the damaged area with PrepSol and then sand the scratched or damaged area with Norton 3X Sandpaper (p-graded aluminium oxide grain) 60, 80 or 100 grit sand paper, sand wet or dry with a rubber sanding block.
          Use a tack rag and wipe the area, using a light pressure
          Only use filler (3M™ Acryl-Green Spot Putty) if it’s essential to the e repair, if used incorrectly it will flake and significantly reduce the effective life-span of the repair. Fill any minor indentations with 3M™ Acryl-Green Spot Putty,  allowing approx. 30 minutes before you shape / sand
          Sand the wheels until you've removed the scratches, `kerbing' marks and/or smoothed the filler flush with the wheel surface.
          Powder coat is harder to sand than paint, so be prepared for prep sanding to take longer
          Continue the sanding process using finer and finer grades of UniGrit paper, 220 or 320 grit and finally with 500-grit paper.
          For small hard to reach places use a Dremel Tool and a suitable sanding bit

Note: To repair damaged powder coatings requires that you completely strip the coating and re-coat, and then bake the finish in ovens. Without heat powder coatings will not cure and the touch-up will simply be a patch but never as good as the original coating.
(For painting / refinishing wheel surface see “Refinishing”)

Removing Surface Scratches:

The standard OEM finish for wheels is a clear coated aluminum; small scratches and blemishes  can be polished  and the surface finish  can be renovated ‘as new’ The clear coat on wheel surfaces is usually thicker than that of the main paint surfaces, but check with a PTG before you start to polish.

Use a 3-inch foam pad and a polishing compound (polish selected is dependent upon the extent of damage) it may take a few passes; follow with a soft foam pad and a finishing polish (Menzerna SF4500).

Felt Polishing Cones - if you're faced with polishing tight places, try some versatile polishing wheels. They come in various sizes and shapes to complete just about every polishing project-wheel, intake manifolds. Fitted to an electric drill they will quickly restore an ‘as-new’ OEM finish.

Brut Spot Shot - sand blaster; a complete hand-held recovery blaster system for a fraction of the cost of an ordinary, vacuum blaster, ideal for small jobs in enclosed areas; grit is captured, forced back into the filter bag, and recycled. It’s virtually dust-free; no mess, no hassle, no need to work outside. Blasts a small pitted or rusted area right down to bare metal in seconds! Comes with the revolutionary Pit Grit, a high-tech blend of several space age abrasives when rust is the problem, Pit-Grit is the solution! Weighs 6 lbs - UPS shippable

Surface Preparation
·         Ensure wheels and rotors are cool before applying cold water as this may cause them to warp.
·         Hose off as much initial grime as you can.
·         Rinse up into the wheel well to wash away road kill, mud and other debris.
·         Use detailing clay and lubrication to remove any embedded contaminants
·         Use a d-limonene (citrus) based cleaner to remove any road tar or oil. Apply P21S® Total Auto Wash  to wheel surfaces and let soak in, agitate with a long-handled boar’s haired brush before rinsing
·         Spray P21S® Wheel Cleaner (Gel or Liquid) this cleaner is 100% acid-free and will not damage any type of wheel finish. (Gel for badly soiled and regular for normal soil) onto wheel rims and let soak in (for badly soiled surfaces us P21S®-Red (422) or Sonax Wheel Cleaner both are formulated with neutralised acid salt
·         Used the P21S® Polishing Soap on the clean wheel to polish the lips, inner wheel, and face of the wheel. (agitate lightly on the clear coated parts)
·         Before finally removing cleaner, agitate with a soft brush and then rinse off

Refinishing

Be cognizant that its common practice on some alloy wheels (among others BMW and Audi use this method (i.e. a light coat of silver over black base paint) to obtain a two-tone shadow chrome finish) In some instances using a harsh acid or alkaline will remove the thin layer of silver exposing the black basecoat and then the primer coat, which gives a similar appearance to acidic surface damage.  

See also Personal Protective Equipment (PPE)

Be cognizant that most European OEM wheels are powder coated, so paint won’t be an exact match. Place the can in a bucket of hot water for ten minutes prior to spraying. This lowers its viscosity and it will spread more evenly without ‘runs’, it also  raises the temperature of the air inside, which in turn  increasing the pressure, enabling a much better spray ‘pattern’ resulting in a better finish.

          Remove the damaged wheel from vehicle.
          Deflate the tyre by unscrewing cap and pushing in valve, once the tyre is flat push the tyre wall down (gently) by standing on it, and then  tuck masking tape underneath the wheel rim, working your way around slowly
          Molecular Tech Coatings Inc., EFS-2500 aircraft paint stripper is environment friendly. It can get easily decomposed and is also non-toxic as well. In terms of chemical composition, there is no methylene chloride, no carbonic acid, and no formic acid present in the paint stripper. Hence, it is perfectly safe to use.
          Clean the damaged area with PrepSol and then sand the scratched or damaged area with Norton 3X Sandpaper (p-graded aluminium oxide grain) 60, 80 and finishing with 100 grit sand paper, sand wet or dry with a rubber sanding block.
          Tack clothes helps control dust by picking it up off the surface and also helps eliminate static that attracts dust. Use a tack rag and wipe the area, using a light pressure
          Only use filler (Bondo Lightweight Filler 264 and Red Cream Hardener) if it’s essential to the repair, if used incorrectly it will flake and significantly reduce the effective life-span of the repair. Fill any minor indentations with Bondo, allowing approx. 30 minutes before you shape / sand
          Sand the wheels until you've removed the scratches, `kerbing' marks and/or smoothed the Bondo filler flush with the wheel surface.
          Continue the sanding process using finer and finer grades of UniGrit paper, 220 or 320 grit and finally with 500-grit paper.
          For small hard to reach places use a Dremel Tool and a suitable sanding bit

Note- If the above cleaning method don’t finish to wheels to your liking have them bead blasted

Repainting (cast aluminium) Wheel Surface

See also Personal Protective Equipment (PPE)

OEM Factory wheel finishes are either an acrylic polymer or a polyester powder coat process, which is the most durable finish you can use. The following Würth products will result in a durable re-finished repaint colour match

·         Molecular Tech Coatings Inc., EFS-2500 aircraft paint stripper is environment friendly. It can get easily decomposed and is also non-toxic as well. In terms of chemical composition, there is no methylene chloride, no carbonic acid, and no formic acid present in the paint stripper. Hence, it is perfectly safe to use.
·         Prepare the surface by removing all sandpaper residues with a tack rag, wash surface and then dry thoroughly. .
·         Use 3M Painters Masking Tape between the tyre and the wheel rim (or use Vaseline to mask the tyre from paint overspray)
·         Wipe-down the wheels with DuPont Prep Sol and allow to air dry.
·         Apply a thin coat of 1z 'Haft-Grund' Self-etching Primer to stabilize and provide an etched surface.
·         Use at temperatures between 70 – 90.oF (.Do not use this paint in damp conditions)
·         Shake the can well for at least a full minute
·         Push the spray nozzle as you sweep across and release at the end. 
·         Spray on, spray off.  Spray on, spray off; apply as a very fine / thin coat.  
·         Paint the wheels with two thin coats of silver alloy paint (Wurth German Alloy Silver Wheel) to ensure complete coverage
·         Apply your first coat of clear then allow it to dry to the touch before applying your next coats. This ‘tack coat will help stop the paint from sliding into ‘run’ formation.
·         Allow air-drying; 1-2 hours on final coat and then lightly sand finish, then leave to cure overnight.
·         Finish with a clear lacquer paint (Würth European Blend Lacquers) apply two or three thin coats of clear with about 20-30 minutes of drying time between coats to seal the silver metallic paint and add depth and gloss
·         A allow clear coat to air-dry and then cure for 4-6 ours
·         Apply a sealant for protection
·         If your axle/ wheel centres (hats) are cast iron, you may want to consider painting the hat area with some hi-temp black engine paint
Product details

Audi, BMW, Mercedes-Benz, Porsche, VW, and most other European OEMs use a cast aluminium alloy wheels. They're usually painted silver and have a clear coated finish or have a silver powder coated finish

1.        1z 'Haft-Grund' Self-etching Primer - bare metal (steel or aluminium) wheels should be primed first with a self' -etching primer and is lead and cadmium-free Applied under a topcoat of urethane paint provides a secondary method of protecting the steel from corrosion. This primer bonds to bare metal and forms a base suitable for synthetic resin, acrylic lacquer and nitro combination paints. A single can will prime two wheels

Warning - Do not use this primer on painted or clear-coated wheels where you are touching-up scuffs and scrapes. A self-etching Primer is for use only on wheels that have been taken down to bare metal.

2.        Würth German Alloy Silver Wheel Paint (Aerosol) can be used as a spot touch-up or whole wheel repaints, one can is enough to coat two complete wheels. This paint is unusually user-friendly, it’s a fast-drying lacquer that matches the standard wheel paint or powder coated finish used by Porsche, BMW, Mercedes, VW, Audi and most other European OEMs. One aerosol restores two complete wheels. to match the OEM gloss of new vehicles

3.        Würth European Blend Lacquers (Aerosol) - used for all German (silver) painted wheels, to match the OEM gloss of new vehicles. This paint is unusually user-friendly, it’s a fast-drying lacquer that matches the standard allow wheel paint use by Porsche, BMW, Mercedes, VW, Audi and most other European OEMs. Wurth German Alloy Silver Wheel Lacquer can be effectively used for spot repairs or full wheel restoration. One can is enough to coat two complete wheels. For the best results, use at temperatures between 70 and 90.0F

Prevention is better than cure
Protect Your Alloy Wheels from Kerb Damage - RimPro-Tec - http://www.rimpro-tec.co.nz/kit-accessories.html


Brembo Brake Callipers

Brake Calliper Renovation

A way to spice up the look and at the same time protects the callipers from corrosion.
The Calliper Paint System (G2- Manufacturing, Inc. Colorado Springs) features aircraft quality paint, available in six different high gloss colours, Red, Yellow, Blue, Silver, Black, and Purple. 

The brush-applied paint is heat resistant up to 932.OF; this paint won't start running into your brake pads, it also seals and protects against corrosion; it also dries much harder than any rattle-can product

Brake dust and dirt will not adhere to the calliper surface since adding the paint. The kit includes everything you'll need to get the job done, besides paint you'll also get reactor (special bonding agent), high tech calliper cleaner, mixing sticks, and a brush. Do not attempt to paint the rotor contact surface - http://www.g2usa.com/product/G2.html

See also Personal Protective Equipment (PPE)

Surface Preparation
          
Remove the brake callipers from vehicle.

          Molecular Tech Coatings Inc., EFS-2500 aircraft paint stripper is environment friendly. It can get easily decomposed and is also non-toxic as well. In terms of chemical composition, there is no methylene chloride, no carbonic acid, and no formic acid present in the paint stripper. Hence, it is perfectly safe to use.

          Thoroughly clean with PrepSol and then use either a 3M Scotch-Brite Red (07447) scuffing  pad or sand with Norton 3X Sandpaper (p-graded aluminium oxide grain) 60, 80 or 100 grit sand paper, sand wet or dry with a rubber sanding block.
          Use a tack rag and wipe the area, using a light pressure
          Continue the sanding process using finer and finer grades of UniGrit finishing paper, 220 or 320 grit and finally with 500-grit paper.
          For small hard to reach places use a Dremel Tool and a suitable sanding bit
          Finally use a tack rag and  then wipe the area, using isopropyl alcohol (IPA)

Refinishing
·         
Prepare the surface by removing all sandpaper residues with a tack rag, wash surface and then dry thoroughly - 

·         Wipe-down the wheels with DuPont Prep Sol and allow to air dry.
·         Apply a thin coat of self-etching primer to stabilize and provide an etched surface.
·         Use at temperatures between 70 – 90.oF (.Do not use this paint in damp conditions)
·         Shake the can well for at least a full minute
·         Push the spray nozzle as you sweep across and release at the end. 
·         Spray on, spray off.  Spray on, spray off; apply as a very fine / thin coat.  
·         Paint the wheels with two thin coats of high-temperature paint  to ensure complete coverage
·         Apply your first coat of paint and then allow it to ‘dry to the touch’, before applying your next coats. This ‘tack coat will help stop the paint from sliding into a ‘run’ formation (orange peel).
·         Allow air-drying; 1-2 hours on final coat and then lightly sand finish, then leave to cure overnight.
·         Finish with a clear lacquer paint,  apply two or three thin coats of clear with about 20-30 minutes of drying time between coats to seal the silver metallic paint and add depth and gloss
·         A allow clear coat to air-dry and then cure for 4-6 ours

Notes:
1.        Cover any lettering that you don’t want painted with a thin coat of Vaseline
2.        Do not attempt to paint the rotor contact surface

I would like to think that these articles become an asset to anyone who is new to detailing and to professionals alike, as well as industry experts who seek to advance their knowledge.

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.

I would appreciate it if you would share this article as it helps other detailers further their knowledge.
Questions and/ or constructive comments are always appreciated.


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