The hand-finished car wash for paint you actually care about.

What actually scratches paint

Swirl marks are not bad luck. They are a record of what touched the panel and whether that thing was holding grit at the time.

Two-bucket wash1,200 gsm mitt

• 40 to 60µmFactory clear coat on a typical modern car
• 1 to 3µmDepth a swirl needs to scatter light and dull the finish
• 7MohsHardness of road silica, against roughly 3 for clear coat
• 1carMitts we use per vehicle before they go back to the laundry

Identify the defect before anyone reaches for a polisher

Four things that touch paint, and what each one holds

• Nylon monofilament brush

  Older in-bay automatics and self-serve foam wands

  Build0.25 to 0.40 mm filament, Mohs 2.5 to 3Grit behaviourGrit wedges into the bundle root and stays there until the bristle is replacedDefect it leavesStraight deep scratches and pigtails

• Closed-cell foam wrap

  Most modern soft-touch tunnels

  BuildPolyethylene foam finger, 60 to 90 mm wideGrit behaviourClean when new, but silica embeds in the cell walls as the flush water loads upDefect it leavesEven micro-marring across the whole panel

• Neoprene cloth strip

  Cloth friction tunnels running 60 to 120 cars an hour

  Build2 to 4 mm ribbon, heavy slurry carryGrit behaviourHolds wash slurry between vehicles, so car 40 gets car 39's driveway gravelDefect it leavesSpiderweb marring, worst on the hood and trunk

• Split-fibre microfibre mittWhat we use

  Our two-bucket hand bays

  Build1,200 gsm, 80/20 polyester-polyamideGrit behaviourGrit falls through the guard into the rinse bucket instead of being dragged backDefect it leavesNone we can find under LED inspection

Depths and hardness figures are industry typicals used here as sample figures for a demo business.

Brine season, and the parts of your car it hides in

Middle Tennessee pre-treats roads before the forecast turns. The salt is on the tarmac a day before the ice is, and it stays on your underbody long after the roads look dry.

Undercarriage lane1,400 psi

1. NovFirst pre-treat runs, usually on bridges and I-440 ramps
2. DecPeak pre-treatment. Brine goes down before the forecast, not after
3. JanHighest chloride load of the season and the most thaw cycles
4. FebResidue keeps reactivating every time humidity climbs
5. MarRoads look clean, frame rails are not. Flush before you stop thinking about it

The bar shows relative chloride load across a season, highest in January. Sample figures.

23.3%

Salt brine concentration crews spray, the point where it stays liquid longest

30 to 40 gal

Sprayed per lane-mile, typically 24 to 48 hours ahead of a winter event

15°F

Below this, brine stops working and blends with magnesium chloride instead

30% RH

Magnesium chloride pulls moisture back out of the air above this, so a dry-looking car is still wet with chloride

40 to 70°F

The thaw window where chloride-assisted corrosion runs fastest, days after the storm

6 events

A typical Middle Tennessee season, sample figure from our own bay counts

Six places the slurry sits

• Rear subframe cradle

  A shallow pan with no drain. Brine slurry sits in it until it is flushed out.

• Frame rail drain holes

  Plugged with leaf litter by November, so the rail fills instead of draining.

• Brake and fuel line clips

  Plastic clips hold a chloride-soaked film against bare line fittings.

• Rocker seams and pinch welds

  Factory seam sealer stops short of the fold, and that is where rot starts.

• Tailgate lower lip

  Double-skinned, unpainted inside, and it collects spray off the rear tyres.

• Spare tyre well

  Drains through one grommet that is usually missing by year six.

Our winter underbody pass, 12 minutes added to any wash

1. 01Undercarriage manifold21 nozzles at 1,400 psi and 5 gpm while the car rolls forward at walking pace
2. 02Chloride-neutralising rinsepH-neutral salt-soluble surfactant held on the underbody for 90 seconds
3. 03Rocker and wheel-well passHand lance into wells, pinch welds and the tailgate lip
4. 04Wax-fortified sealA thin film on the rockers and lower doors so the next round of spray runs off

We measure the clear coat before we polish it

Polishing removes paint. On a car that has already been corrected once, there may not be enough left to remove. So we read the film first and put the number in writing.

Ceramic roomFilm gauge

12

Gauge readings we log per car: four horizontals, four verticals, both doors and the roof

1.5 to 3 µm

Removed by a one-step finishing polish

4 to 8 µm

Removed by a compounding step, which is why we do not run one on every car

25 µm

The clear-coat floor we refuse to go below, whatever the customer asks for

• 130 to 160 µm totalHealthy factory filmOne-step polish is safe. Expect 1.5 to 3 µm removed and most wash marring gone.
• 100 to 129 µm totalThin but workableSingle refining pass on a soft foam pad only. We skip compound and skip panel edges entirely.
• Under 90 µm totalPreviously corrected or sandedWe seal, we do not cut. Polishing here risks burning through to primer on a body line.
• 175 µm and overRepainted panelWe test a 2 in square first. Fresh paint needs 30 to 60 days to gas out before any sealant goes on it.

Readings are taken with a magnetic and eddy-current gauge on steel and aluminium panels. Figures shown are samples.