I am not sure if this has been covered here before, I did a search but didn't find anything so thought I should share my experience with these processes.

We had previously sand blasted a couple of shells, but this doesn't remove the underbody sealer which means several days with a heat gun, scraper and loads of graft. I then found a company that could remove the sealer and paint by heating the shell in an oven. This requires the shell to be stripped of every single part, including the loom. One other problem arises with LWB cars, the heater silencer in the sill (rocker) has plastic ends which get destroyed in the oven. SWB cars have a steel silencer so there is no problem. The solution is to cut off the outer and inner sills and remove the silencer, not a problem with the usual full restoration as these are invariably in need of replacement anyway, but I need to find a solution for shells that don't need the fully monty, possibly opening up the rocker from the passenger compartment, removing the silencer, then welding it back afterwards.

The oven process leaves the shell bare and unprotected. The next process can be carried out immediately or after any welding work. The steel is passivated by immersing the shell in an alkaline solution for 3 days to disolve away any oxidation. This process leaves the steel as clean and shiny as the day it was made.



The shell must then be protected immediately by an Ecoat, an electrophoretically applied zinc phosphate.





This shell then underwent the full restoration treatment with new sills, inner wings etc. etc.



The shell that we are working on at the moment has only been through the oven process, we will get it passivated and ecoated after the welding work, replacing the heater silencers with flexible ducting so that they don't get clogged up with the Ecoat immersion.

One major problem that must not go unmentioned is the way the shell distorts in the oven due to the temperatures used. The door aperture lozenges back unless it is braced.