In the last blog post the painting or surface treatment process was discussed. Before we leave that field a few word about the surface inside the body structures in the need of rust protection and the equipment used. It must be emphasized that the equipment used here only is intended for rather small areas after a repair job, not for treatment of whole cars. The equipment consists of three different parts, the suction tube and two different guns. One for each rust inhibiting product, see Image 1-2 and the text below. The suction tube and the gun are kept together by a compressed air valve.
As already told, the rust protection work should be performed after the painting process. Otherwise the paint adhesion can be suffering. The rust protection product can be divided into two different types.
1. A thin product suitable for closed areas such as box sections. 2. A sturdier product suitable for the surface under the car. Can usually also be purchased in a heavy duty version for use in wheel houses and similar areas exposed for wear from stone chips from the road surface.
Both products are packaged in different sizes, from spray cans up to barrels. The most practical size in a DIY garage or a smaller workshop is the 1 liter can which can be seen in Image 1 and 2.
The gun in Image 1 is used for rust proofing the underside of the car. After use the whole equipment must be cleaned thoroughly. If not, the petrol product residues in the gun dry fast and make the gun unusable. An empty can filled with solvents to can be used to wash the gun. Note that the nozzle is adjustable for a correct function.
The gun in image 2 has a flexible probe for spraying in closed areas, often after drilling hole for the probe. Sometimes the hole shall be plugged after the treatment. There are special plugs for the purpose. More information can be found in the book.
To avoid dripping in the workshop of the thin rust protection oil from the probe not in use, the probe is kept in the device in Image 3. A 20 mm wide tube with a suitable length is fixed to a wall. At the bottom of the tube a glass can, Image 4, collect the drips keeping the floor clean.
The door we are going to repair here, Image 5, is from a Porsche 911 police car at the Police Museum in Stockholm. The Swedish traffic police used a few Porsches between -65 and -73. One of them was kept as a museum object.
Even a car stored under ideal conditions and not in regular use can develop rust. The reason in this case is that most of the rear end of the door is made from two layers. Use in rain has trapped humidity through the years between the layers and the area above the tape strip in Image 6 must be replaced by a fabricated panel. Replacement parts do not exist.
The creation of a replacement panel began by making a card board template of the most crucial part, Image 7. With help from that template a simple shaping tool was made from plywood, Image 8. For information about the plywood quality, see the book.
To be continued.....