Episode 10 of Retropower’s Gordon Murray Mk1 build follows the shell through the bodyshop, from bare metal to the moment it goes into the booth for its final colour. Retropower’s bodyshop team, Gaz and Marc, explain each layer and why it’s there. Meanwhile the suspension parts, engine and struts head out to specialists.
Video: Retropower on YouTube · watch “Gordon Murray's Mk1 Escort - Retropower Build Episode 10” on YouTube
What happens in Episode 10
Epoxy first (1:16). A freshly blasted shell starts to rust within hours in damp air. So after the zinc spray underneath, the outside goes straight into epoxy primer on bare metal. That means nothing gets trapped under later layers, however long the shell waits.
Filler and polyester (2:19). Next comes seam sealing, and then a little filler, as most panels are new. Filler and metal sand at different rates, so the whole exterior gets a coat of sprayable polyester and a guide coat, then it’s block sanded flat. Filler and polyester are porous. Moisture trapped under paint expands with heat or cold and causes micro-blisters, which is why the shell is kept dry.
Underside and hidden areas (4:22). The underside, the interior and anything hidden by trim or carpet are coated in a tinted urethane coating, U-POL Raptor, which was first made for pickup truck beds. It wears better than ordinary paint where carpet and trim rub. The area under the front wings is where many Escorts rotted. So that area and the underside of the wings were coated with the wings off. The weld areas were masked, then the wings were aligned and welded on, cleaned, seam sealed and coated again.
Final alignment (6:55). The doors, bonnet, boot lid, grille and lights are fitted with their latches and seals, because seals change where a panel sits. The polyester is then blocked across the panel gaps, so the reflections run straight along the side. The shell is taken down to 320 grit, then given a second coat of epoxy, which seals the porous layers.
Last steps before colour (9:07). Visible seams in the engine bay and gutters are sealed only now, so that rigid polyester never sits on flexible sealer. The whole shell is then wet sanded to 800 grit, because dry sanding clogs the paper and leaves marks. The panels come off to be painted separately, so the shuts and hinge areas get full coverage. After baking and curing, the paint will be wet sanded and polished flat, to remove the slight orange peel found on most new cars.
In the booth (12:13). Gaz and Marc talk through the 20 or so days since blasting. The shell is mostly new panels, so the work was mainly filling the joins and sanding. A carbon panel was rejected because it didn’t look like metal. They say bodywork is under pressure because it’s the first thing people notice.
Parts away to specialists (15:21). The rear subframe, wishbones, diff carrier, front crossmember and arms are blasted, zinc sprayed and powder coated. The engine has gone back to Cosworth for its final build, and Nitron is building the struts from the dummy units, with the lengths and reservoir positions supplied.
Timeline (18:17). Retropower usually budgets 250 to 350 hours for prep and paint from a bare shell, and says this car is within that. It has 20 or more projects running with a team of about ten. It expects a build like this to take around 18 months to two years, and says this one is on track.
Parts, tools and suppliers mentioned
- Epoxy primer (two coats), seam sealer, body filler, sprayable polyester and guide coat
- U-POL Raptor urethane coating, tinted to body colour
- 320 and 800 grit abrasives; wet sanding, then flatting and polishing after paint
- Zinc spray and powder coat on the subframes and suspension arms
- Cosworth (engine final build) and Nitron (struts)
Lessons for your own Mk1
- Prime with epoxy straight after blasting. Bare steel starts to rust within hours.
- Keep filler and polyester dry until they’re sealed, or blisters can appear later.
- Protect the inner wings before the front wings go on. That’s a classic Escort rust trap.
- Block sand with doors, seals and lights fitted to get straight panel gaps.
- Most of a paint job is prep. Retropower says applying the colour takes about three hours of the total.
Mk1 context
Rust behind the front wings and in the inner wing areas is one of the best-known Mk1 Escort weak spots, which is why Retropower coats those areas before the wings are welded on.
Related
- Series hub: all Retropower Gordon Murray Mk1 episodes
- Background: the complete history of the Mk1 Ford Escort
- More builds on video: Mk1 Escort build videos