How to paint a car and the processes involved
This page is currently being revised
The guide below outlines some of the procedures involved in painting a car. All the following procedures help to achieve one of two goals. Either helping to ensure the longevity of the work we carry out or ensuring the body is straight and free from defects.
Bare metal processes: A car body may require partial or full bare metal processing. If the cars current paint integrity is good then bare metal may not be necessary. Bare metal paint jobs do help to ensure the longevity of our work as we know the condition of the metal underneath and the state of any previous repairs.
- Localised micro blistering (tiny little blisters often found in clusters). If a panel or section of a cars body shows micro blistering that panel or area will need to be stripped of the current paint layers as the cause is usually tiny pores of rust on the metals surface. These must be removed and treated or they will come back. ruining the new paintwork. For example an MGB front wing will take in the region of 3 hrs to manually remove the paint.
- Stripping and dipping: The car body is sent to a specialist like SPL or Envirostrip for chemical stripping expect to pay £3500+ depending on size of vehicle. The body must be completely dismantled (engine out, all ancillaries, wiring loom etc..) this can take a couple of weeks and everything that comes out also needs to go back in which inevitably takes longer estimated cost to dismantle and reassemble £4000. Some reports suggest that acid may seep out of joints over time if not properly neutralised by the strip and dip company. Dip stripping then / ecoating is probably the best solution as it will coat hidden surfaces like chassis leg internals.
- Media blasting. Media blasting need not involve as in depth dismantling as Stripping and dipping but can result in costly repairs rectifying the damaged done should the panels be distorted. Panel distortion is common in this process even with soda blasting (which does not remove rust – blasting companies will use a course media to remove rust and fillers) but a lot depends on the competency of the media blasting company and the time taken to complete the job. expect to pay a reputable media blasting company £2500+ to blast a car shell. Please also note that blast media collects in every joint, corner, box section of a vehicle and can take days to clean out prior to painting (additional cost factor).
- We will often combine process. We may hand strip the upperbody and have the underbody blasted. This gives good controllable results. Although not as thorough as dipping
- Please also bare in mind that with bare metal processing even if your car looks to be in good shape it may be returned to you looking like a sieve.
Replacing rusted metal. If your car body shows bubbling or holes then those areas will need to be replaced with new metal. We weld in new panels using various techniques depending on the area that requires work. For think steel sections will mostly use Mig welding. For thin external sheet metal such as door skins we will often weld with TIG or oxyacetylene to minimise panel distortion or for a near invisible repair to the metal. We do not repair holes and rust with fillers or fibreglass. We can also weld aluminium. Cost of welding varies depending on the size, shape and nature of the repair. An outer Sill panel may take approx. 4-6 hours to remove without causing damage to surrounding panels and 3hrs to put a new one on depending on panel fitment quality..
Making or replacing body panels. Quite often on classic cars panels are just not available or cost a considerably more then expected. In these circumstances we will often make a panel or repair section in house. We will make a template of the panel or section and reproduce it by hand from sheet metal steel or aluminium (as required) A small section with a complex shape section can take anywhere from 2hrs too two days to make. Full panels will often require a week or more to produce.
Car body paint preparation – Before we put any paint on a car we need to feel confident that the body is dent free and in proper shape. Old tired paintwork hides small dents and undulations very well. The shinier and smoother paintwork is the more small defects will stand out.
The preparation of a bare metal car body starts with hammering/ plannishing dents out. Very shallow or inaccessible dents may have a light skim of filler to bring them level. Next we apply an epoxy coating. Epoxy is a tough, resilient, non-porus coating with anti corrosion properties. The epoxy coating is then sanded flat to visually reveal any imperfections that are then corrected. Estimated 30hrs depending on car size. The body then follows on to the stage outlined below.
When working over an existing paintwork the surface is first course sanded to initially flatten the panels and key (abrade to increase surface area and promote paint adhesion) the surface. Then the body is primed and sanded with any defects being rectified. 30+hrs
Panel gaps. As well as removing windows, lights, bumpers, mirrors and trim we check the car body panel gaps. Aligning panels especially on cars that have had previous accident damage or sills replaced can be very challenging and often will take a day to complete.
Paint application. Generally speaking every paint job we do usually requires at least 2 smoothing/sanding procedures before we are confident and happy to apply paint. A single colour paint application takes on average 2-3 days to complete. First we mask of any openings or areas that are not going to be painted (approx. 4/6 hours ). Then the body or parts have to be thoroughly cleaned and degreased. Once everything is ready the final clean involves using a tac cloth to remove any dust that may have settled. Usually there are multiple booth setups for instance on a shell we will often paint the interior first then re-mask for the exterior then paint all off panels and small parts. Some paint jobs such as candy and multiple colour work take 5 days to apply the paint please click here for an example- candy red AC Cobra
Paint finishing. Although we always strive to take every precaution to get the paint to lay as well as possible inevertably there is allways some remedial work required and paint finishing. The paint finish process is often refered to as colour sanding or flatting and polishing. This involves sanding the entire vehicle down again and then buffing the paint back up to a high shine taking around 3 days+ to complete.
*Paint work inspection will result in possible paint corrections procedures.