SHOCK HORROR No. 1: In August of 2016, I discovered that the rear sub-frame of my 1972 T100R which I had painted 3 months previously and stored in a shed, had the paint "bubbling" up in places, and a scrape revealed that it was rust forming on the steel! That sub frame previously had all the old paint removed, and was treated all over with a tannic acid type rust converter, to deal with the patches of rust that remained after sanding. I had then sprayed on a coat of a "primer/surfacer" and followed with top coats of an "epoxy-enamel", both from aerosol rattle-cans.
I removed all the paint from that sub frame in August 2016, and treated the frame with a water based product that is described as a "Rusty Metal Primer", made by the same company that made the rust converter that I used three months earlier. I then applied the same "primer/surfacer" and "epoxy-enamel".
SHOCK HORROR No. 2: A couple days ago I discovered "bubbles" again under the paint of that same sub-frame I painted in August of last year, and had bolted on to the frame, which was standing propped up on its centre-stand on my veranda! A scraping with a razor blade confirmed that it was yet again rust! I can't even get the bike together before the rust develops! I do live in a sub-tropical climate near the ocean.
So, what am I to do? I appear to be cursed by a Rust Demon! Should I remove the paint from the areas where the rust is developing and remove all rust down to bare metal with phosphoric acid, then repaint those areas, assuming no more rust will pop up under the "good" area? Or, should I remove the sub-frame and strip all the paint off and totally de-rust it with acid, then apply a zinc-rich primer before top coating? Or, should I consider the powder coat option? I understand that a zinc-rich powder coat can be applied first, followed by the finishing coat.
Any thoughts?
I removed all the paint from that sub frame in August 2016, and treated the frame with a water based product that is described as a "Rusty Metal Primer", made by the same company that made the rust converter that I used three months earlier. I then applied the same "primer/surfacer" and "epoxy-enamel".
SHOCK HORROR No. 2: A couple days ago I discovered "bubbles" again under the paint of that same sub-frame I painted in August of last year, and had bolted on to the frame, which was standing propped up on its centre-stand on my veranda! A scraping with a razor blade confirmed that it was yet again rust! I can't even get the bike together before the rust develops! I do live in a sub-tropical climate near the ocean.
So, what am I to do? I appear to be cursed by a Rust Demon! Should I remove the paint from the areas where the rust is developing and remove all rust down to bare metal with phosphoric acid, then repaint those areas, assuming no more rust will pop up under the "good" area? Or, should I remove the sub-frame and strip all the paint off and totally de-rust it with acid, then apply a zinc-rich primer before top coating? Or, should I consider the powder coat option? I understand that a zinc-rich powder coat can be applied first, followed by the finishing coat.
Any thoughts?