Hello, Lettie.
Our roof was rusting so we used Boysen Metal Etching Solution. However, we were not able to immediately apply primer since it had turned night time already. What we did is to just thoroughly wash our roof with water.
Kindly advise on what we should do next. Do we repeat the application of Boysen Metal Etching Solution the next morning? Or can we proceed with primer for our roof?
Thank you for your reply.
From,
Boysen User J
—
Hi, Boysen User J.
Technically, both of what you suggested are correct. It just all depends on the state of your roof now!
When to Reapply Boysen Metal Etching Solution
You will repeat the application of Boysen Metal Etching Solution if you still see rust on your roof the next morning. To use Boysen Metal Etching Solution, apply the rust converter to affected areas and wait for 10 to 15 minutes.
Then, remove the remaining rust converter on the surface. I noticed you used water for this step last time but it will be better to use thinner afterward too. Wet a rag with thinner and wipe the areas where you applied the rust converter.
Both of these will remove the rust converter from your roof after it has done its job. It can’t be left on your roof as it’s a corrosive substance and can also damage metal if not washed off. When your roof is dry, immediately apply primer. Wait for your primer to dry, then apply topcoat.
When to Proceed to Primer
On the other hand, if you’re sure that your roof is now rust-free, you can skip doing rust treatment again and already apply primer. Prime areas where you carried out rust treatment the day before and wherever you see bare metal.
Wait until the primer is dry then go ahead and apply your chosen topcoat. Remember to use an appropriate primer for your chosen topcoat. If you’re unsure, best check your topcoat’s painting schedule.
Why Prime Immediately After Rust Treatment
There’s a good reason why we recommend applying primer immediately after carrying out rust treatment. It’s to avoid flash rusting.
Flash rusting is when rusting occurs on a metal surface immediately after you’ve done surface preparation procedures. This is usually caused by treating rust improperly or insufficiently. As much as possible, you want to avoid that because it will mean you would have to do rust treatment again. Yikes. So, avoid that by immediately applying primer.
Here’s a video tutorial as well if you need additional help.
That’s it! Hope I’ve been helpful. Good luck!
Your painting partner,
Lettie
Need advice? Paint TechTalk with Lettie is here for you. Comment your painting question below or send an email to ask@myboysen.com.
