Just used both on my trailer. Not at the same time and on different parts. I thought they would be the same but they are different. Mentioning this for the benefits of people like @Dcal
Both are high build epoxy mastic primers. Both have aluminium powder in them to provide extra corrosion protection. The data sheets are very similar.
In practice though I noticed quite a difference. The 87 was even thicker and almost impossible to mix without streaks. When it dried it was like a glossy plastic. The 90 was more of a matt finish. I wonder which will last longer? Both overcoated anyway.
Just as good or possibly even better is the British Leigh's paint which is now Sherwin Williams. I suspect though it is only slightly better but at £185 for 5L I think I will pass
I brush applied - doesn't have to look pretty. For a topcoat I used Jotun Hardtop Pro - very impressed. Already rock hard and a pretty good finish. Better than the flexi I used before.
Both are high build epoxy mastic primers. Both have aluminium powder in them to provide extra corrosion protection. The data sheets are very similar.
In practice though I noticed quite a difference. The 87 was even thicker and almost impossible to mix without streaks. When it dried it was like a glossy plastic. The 90 was more of a matt finish. I wonder which will last longer? Both overcoated anyway.
Just as good or possibly even better is the British Leigh's paint which is now Sherwin Williams. I suspect though it is only slightly better but at £185 for 5L I think I will pass
I brush applied - doesn't have to look pretty. For a topcoat I used Jotun Hardtop Pro - very impressed. Already rock hard and a pretty good finish. Better than the flexi I used before.