THE 1966 UNDERCARRIAGE PROJECT - LONG POST!

17 | 09 | 22 | 21:01 | Filed in: 1966 Cadillac Coupe deVille | Restoration

Last fall (2021) the undercarriage project of my 1966 Cadillac Coupe deVille started. The car is in fantastic condition. The factory or dealer applied rubberised undercoating was still on the car, but on some areas it was dry and brittle. In areas where it was not applied there was some slight surface rust which I also completely removed.

VIDEO RECAP

I did not plan to do a video about the restoration, but here is a short collage of some footage I had: (on youtube you can watch it in 4k HDR

This is a short video showing what was done

BEFORE

Some "BEFORE" pictures showing how the car looked before I started working on it.

AFTER

This is how it looks now - after all the work I did. Click to see the full report.

1966 UNDERCARRIAGE CLEAN UP PROJECT

03 | 11 | 21 | 16:20 | Filed in: 1966 Cadillac Coupe deVille | Restoration

I am planning to clean up the undercarriage of my 66 Coupe deVille during the long winter months. The car is in fantastic condition. There is still the original undercoating on the car. In areas where it was not applied there is some slight surface rust which I would like to remove and conserve everything.

To make the car perfect again I will also dry ice blast the undercarriage and totally clean it up like I did on my 74 and the Roadmaster to preserve it as good as possible.
Today I started to brush some of the surface rust away. After that I will apply some rust remover.
I took some "before" pictures and a video.

It will be a long and dirty job…

CLEANING THE UNDERCARRIAGE OF THE "NEW" 1996 BUICK ROADMASTER

19 | 05 | 18 | 18:35 | Filed in: 1996 Buick Roadmaster | Restoration

A project that kept me busy for the last few months was to bring back our "new" Roadmaster to its former glory. The car has only 23k miles on the odometer and in many areas still looked like new. The undercarriage was not protected very well from the factory and like on all cars had developed some surface rust over the last 2 decades although the car never was stored outside nor regularly driven in the rain. It also never saw road salt or snow during its entire life. Below are some before pictures where you can see the fantastic condition the car was in before I started cleaning it up.

This is how the car looked like after dry ice cleaning.

DRY ICE BLASTING THE UNDERCARRIAGE OF THE 1974 CADILLAC

29 | 10 | 15 | 18:53 | Filed in: 1974 Cadillac Coupe deVille | Restoration

I´m restoring the undercarriage of my 1974 Cadillac Coupe DeVille. See below.
As I want to do it as perfectly as possible, I wanted to remove all the undercoating which was applied when the car was new.
I do not like rubberized undercoating, as you cannot see whats going on underneath. It can trap moisture and once it flakes off due to corrosion, there is already some major damage in the metal underneath.

There are different methods for removing the undercoating and most of the methods are a pain in the a**.
This stuff can be removed with a scraper and chemicals, or with heat and a scraper. Both methods will damage the metal underneath and scratch the paint on the underbody, and it takes forever…

As I did not want to use any of the methods mentioned above, I decided that I wanted to try dry ice blasting.

Dry ice-blasting is a form of carbon dioxide cleaning, where dry ice, the solid form of carbon dioxide, is accelerated in a pressurized air stream and directed at a surface in order to clean it. An alternative media for non-abrasive blasting is water-ice, known as ice blasting.
The method is similar to other forms of abrasive blasting such as sand blasting, plastic bead blasting, or soda blasting but substitutes dry ice as the blasting medium. Dry-ice blasting leaves no chemical residue as dry ice sublimates at room temperature.
Dry-ice blasting involves propelling pellets at extremely high speeds. The actual dry-ice pellets are quite soft, and much less dense than other media used in blast-cleaning (i.e. sand or plastic pellets). Upon impact, the pellet sublimates almost immediately, transferring minimal kinetic energy to the surface on impact and producing minimal abrasion. The sublimation process absorbs a large volume of heat from the surface, producing shear stresses due to thermal shock. This is assumed to improve cleaning as the top layer of dirt or contaminant is expected to transfer more heat than the underlying substrate and flake off more easily. The efficiency and effectiveness of this process depends on the thermal conductivity of the substrate and contaminant. The rapid change in state from solid to gas also causes microscopic shock waves, which are also thought to assist in removing the contaminant.

Unlike abrasive media blasting you cannot remove rust with dry ice blasting.

I found a company through the website of a classic car club, which is only a little over an hour away. I wanted to have it done before the first snow and as soon as possible, so that I could continue working on my car during the winter. The owner of the company did a great job. He is a very friendly and competent gentleman and it was a pleasure working with him.
Here is a short video how it was done: (make sure to watch in HD for proper image quality)

You can find all the pictures I took today in my restoration album.

The car was lifted with a forklift and then covered in plastic.

One of the rear wheel-housings before blasting - you can see the undercoating everywhere.
The same wheel housing after blasting - all the original paint was still very well preserved under the undercoating. As you can see originally the wheel housing was brown. During painting a lot of overspray from the body landed in the wheel housing. Then Cadillac added rubberized undercoating to protect the metal from stone chips and to keep the car more quiet. Luckily there is no rust to be found anywhere.

During blasting.

The original brown paint showed up underneath the undercoating. The paint is still in perfect condition.

The original paint showed up underneath the undercoating in the wheel housings as well.

After cleaning - it came out really nice! I will touch up some areas and conserve the others with a special transparent coating.

I´m very happy with the result of the cleaning and will now have to protect everything and paint some areas.