charlysays
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- Messages
- 397
- Location
- UK, Wales
For years now I've been preserving my old cars by blasting away rust with a needle scaler which does a reasonable job at removing the bulk of the rust including from craters even in inaccessible areas. It's also good at getting under underseal to isolate the rust from surrounding undamaged metal and quickly working out what needs welding and what doesn't.
Then I'd usually skim with a grinder if possible, two coats hydrate 80, 1/2 coats electrox then dynax/ dynax ub.
This has kept metal which was pretty crusty and flakey from perforating for years and years, so far 8+ years on one car. I'm sure it's bubbling up a bit but it stays solid and sealed up for a very long time when ignoring would've resulted in lots of welding within 2 yrs.
With a top up of dynax every other year I'm confident the car would make 10 yrs without significant issue.
On outerpanels I favour total rust removal via deox gel and/ or welding, then electrox, high bild, then top coat.
However I've read you shouldn't use electrox over hydrate as hydrate forms a barrier preventing the electrox from cathodically protecting the steel.
Can anyone suggest a rust converter which will help further stabilise a needle scaled surface whilst allowing electrox to protect the steel? Or would hydrate with dynax over the top perform almost as well?
Two options I've come up with so far are kurust (it doesn't appear to form a barrier like hydrate 80?) And plain old phosphoric acid 45%. I used the latter on some rusty lower arms and it semi removed / converted the rust to phosphate and it did appear to dry. On cleaner steel it can stay sticky and not finish reacting so I tend to rinse it off then. The issue with phosphoric acid is it's dangerous and can need rinsing off after which isn't practical or safe on a car lift unless your garage is a wet room with a heater and you're wearing a full on chemical suit.
Any thoughts much appreciated.
Currently leaning towards using phosphoric acid to just debulk rust on outer panels to make it easier for deox gel to attack then using kurust under the car to reduce the workload of the electrox as it seems to stabilise rust, isn't dangerous to use, doesn't need rinsing off and doesn't form an impenetrable barrier preventing cathodic protection.
Then I'd usually skim with a grinder if possible, two coats hydrate 80, 1/2 coats electrox then dynax/ dynax ub.
This has kept metal which was pretty crusty and flakey from perforating for years and years, so far 8+ years on one car. I'm sure it's bubbling up a bit but it stays solid and sealed up for a very long time when ignoring would've resulted in lots of welding within 2 yrs.
With a top up of dynax every other year I'm confident the car would make 10 yrs without significant issue.
On outerpanels I favour total rust removal via deox gel and/ or welding, then electrox, high bild, then top coat.
However I've read you shouldn't use electrox over hydrate as hydrate forms a barrier preventing the electrox from cathodically protecting the steel.
Can anyone suggest a rust converter which will help further stabilise a needle scaled surface whilst allowing electrox to protect the steel? Or would hydrate with dynax over the top perform almost as well?
Two options I've come up with so far are kurust (it doesn't appear to form a barrier like hydrate 80?) And plain old phosphoric acid 45%. I used the latter on some rusty lower arms and it semi removed / converted the rust to phosphate and it did appear to dry. On cleaner steel it can stay sticky and not finish reacting so I tend to rinse it off then. The issue with phosphoric acid is it's dangerous and can need rinsing off after which isn't practical or safe on a car lift unless your garage is a wet room with a heater and you're wearing a full on chemical suit.
Any thoughts much appreciated.
Currently leaning towards using phosphoric acid to just debulk rust on outer panels to make it easier for deox gel to attack then using kurust under the car to reduce the workload of the electrox as it seems to stabilise rust, isn't dangerous to use, doesn't need rinsing off and doesn't form an impenetrable barrier preventing cathodic protection.