I have had several interesting conversations regarding the POR-15 and KBS products over the last few months. These have been accompanied with research and some tests.
Basically I have come to the conclusion that,
-Surface prep is everything. If it's not clean, clean and if you don't follow the three step process the product won't stick
-Temperature is very important. To cold or hot and the product won't adhere properly and tends to dry differently and is then subject to peeling off in sheets
-it's a great product when used properly and on items that are (don't know how to discribed this) parts or solid and can be coated in their entirety
-it is also very effective on small parts or sections of the shell that have rust and can be contained or sectioned off
-only use either the (with POR products) POR Tie coat primer or the U-POL Acid 8 etch primer
The problem I have been wrestling with is the use of these type of products on large sections of the shell. The use of water during two of the processes over larger areas allows water (particularly during the wash down phase) to possibly migrate into cavities and joins. This is hard to control. Given that the cleaning process removes all of the oils and waxes that have been helping to protect areas, these cars had very (none) undercoat and the second process uses a chemical reaction to basically induce a controled rust for the next coat to bond onto I have concernes about rust control after the event. So my plan is to continue to use the products in small areas of existing rust that the removal of the section is not warranted or possible and the use of water is minimised. A recent conversation with a panel repairer and a coach builder have strengthened my feeling on this position. It is apparent that the entire section that it prepped needs to be covered with the bonding coat, both sides as this is the only way to stop the process that has been started and seal the metal.
Edited by CBR Jeff, 30 August 2016 - 12:36 PM.