This question it mainly to Barry. The chemical dipping company in Miami said it uses this product to protect against future corrosion from inside out. They spray in all hidden areas as well as the body. I know you generally don’t like anything under your epoxy primer. I figured I still wanted to know what you think. Also if this product wasn’t used how would the inner metal be protected after dipping. Mainly above metal headliner, rocker panels and cab supports. Thank you in advance
Chemical stripping and coating
- Thread starter Tony_C
- Start date
Dean Jenkins
Promoted Users
I'm not Barry and I don't know anything about this product.
But, I had my car "acid dipped," which is actually a misnomer. The body is dipped in a hot caustic solution which removes all paint, filler etc, and is then dipped in acid to neutralize the caustic solution and dissolve rust.
It is then immediately and EXTENSIVELY pressure washed with fresh water to remove the acid.
They then spray a highly diluted, water soluble rust inhibitor over it to prevent flash rusting.
When you get the car home, wash of the rust inhibitor with dawn soap and fresh water.
Every area possible gets 80 grit DA and SPI epoxy. For unreachable areas I used Eastwood chassis primer which comes with up to a 3 foot wand to get into crevices.
After all painting is done, I will go back into those crevices with 3M cavity wax, which also has various length wands.
Here is what it looked like going in:
**If you look closely, you will see the "frenched" antenna hole behind the drivers door. The 80's called and wanted that back, so I sent t to them
Here it is after dipping
Hope that helps.
But, I had my car "acid dipped," which is actually a misnomer. The body is dipped in a hot caustic solution which removes all paint, filler etc, and is then dipped in acid to neutralize the caustic solution and dissolve rust.
It is then immediately and EXTENSIVELY pressure washed with fresh water to remove the acid.
They then spray a highly diluted, water soluble rust inhibitor over it to prevent flash rusting.
When you get the car home, wash of the rust inhibitor with dawn soap and fresh water.
Every area possible gets 80 grit DA and SPI epoxy. For unreachable areas I used Eastwood chassis primer which comes with up to a 3 foot wand to get into crevices.
After all painting is done, I will go back into those crevices with 3M cavity wax, which also has various length wands.
Here is what it looked like going in:
**If you look closely, you will see the "frenched" antenna hole behind the drivers door. The 80's called and wanted that back, so I sent t to them
Here it is after dipping
Hope that helps.
Last edited:
Chris_Hamilton
Trying to be the best me, I can be
You would prime those areas with epoxy. Even with that treatment you are not going to get more than a year or so before it starts rusting if nothing else is used.
I looked at the MSDS of the product. It uses nitric acid so I would think it would need to be neutralized before epoxy could be applied. I'm not a Chemist (Lizer is though) so not 100% certain. I know that Barry has stated that the only metal treatment approved for SPI Epoxy is Ospho and that must be neutralized before applying.
Ask your guy if they could apply Holdtite instead. It can be re-coated with epoxy. It works similar as a temporary rust prevention. Any bare metal you would want to coat with epoxy anyway. Cavities like inside rockers, you can use cavity wax.
A PH of 1.4 to 2.0 per the safety sheet is some strong acid. I used to like to see any strong acids in heavy glass bottles--no plastics jugs. Neutralizing that ain't quite like using baking soda. I'd be very concerned about a person being able or getting that anywhere neutralized adequately outside of a dipping/soaking tank line set-up for use with anyone's epoxy or proprietary "stick to anything" primers.
Yes , very well explained thanksI'm not Barry and I don't know anything about this product.
But, I had my car "acid dipped," which is actually a misnomer. The body is dipped in a hot caustic solution which removes all paint, filler etc, and is then dipped in acid to neutralize the caustic solution and dissolve rust.
It is then immediately and EXTENSIVELY pressure washed with fresh water to remove the acid.
They then spray a highly diluted, water soluble rust inhibitor over it to prevent flash rusting.
When you get the car home, wash of the rust inhibitor with dawn soap and fresh water.
Every area possible gets 80 grit DA and SPI epoxy. For unreachable areas I used Eastwood chassis primer which comes with up to a 3 foot wand to get into crevices.
After all painting is done, I will go back into those crevices with 3M cavity wax, which also has various length wands.
Here is what it looked like going in:
**If you look closely, you will see the "frenched" antenna hole behind the drivers door. The 80's called and wanted that back, so I sent t to them
View attachment 24140
View attachment 24141
Here it is after dipping
View attachment 24142
View attachment 24143
Hope that helps.
Chris_Hamilton
Trying to be the best me, I can be
If it's a strong acid like DAT pointed out, you can't neutralize it that way. It has to be done while it is still wet with the product.
The Sds sheet says phosphoric acid and zinc, zinc is good but too much can compromise adhesion and I don't like it without knowing the percentage of zinc and water is not going to neutralize the acid it if is dry.
So the proper way is to retreat with acid, wait 5 to 10 mins and neutralize when you get to the car.
Not on my car.
Most have gone to holdtite2 as contains no acid but changes the ph of the metal so it won't flash rust on the way home.
So the proper way is to retreat with acid, wait 5 to 10 mins and neutralize when you get to the car.
Not on my car.
Most have gone to holdtite2 as contains no acid but changes the ph of the metal so it won't flash rust on the way home.
Last edited:
Lizer
Mad Scientist
Looks like we need to revisit that acid conversation again.
An acid's strength is determined by its dissociation constant (Ka) moreso than pH. The pH only tells part of the story though it is a function of the Ka. An acid with a dissociation constant greater than 1 is considered a strong acid. Nitric acid is the weakest 'strong' acid with a Ka of 24. Considering this is all on a logarithmic scale, that is just barely a strong acid. It is about 40 times weaker than sulfuric acid, and 54,000 times weaker than hydrochloric acid, which is commercially available on the shelves at Lowes, Home Depot, etc in plastic jugs better known as muriatic acid for cleaning driveways.
pH is a measure of hydronium ions in a aqueous (water-based) solution. A dry substance or surface cannot have a pH. If it aint got water it won't have a pH...there can be some caveats to that but best to leave it there.
Therefore, a panel with acid dried onto it will have no pH unless it is made aqueous (rewet with water). If epoxy is applied to it, and as I believe epoxy is not aqueous (?), my hypothesis/theory the first time we had this conversation was it is not the pH itself that epoxy is affected by, but rather the residue of the acid on the panel which acts like a contaminant and adversely affects binding of the epoxy.
This latter point is why you can apparently get by from rewetting the acid and then rinsing off with water. Because you're simply just rinsing the residue off. But even after the residue is gone, if you were to run more water down the panel and collect it then measure the pH, it would still be very acidic. Water itself won't neutralize any acidity on a panel obviously, but like I said then and again now, my hypothesis is it's not a function of pH but residue/surface contaminant instead.
An acid's strength is determined by its dissociation constant (Ka) moreso than pH. The pH only tells part of the story though it is a function of the Ka. An acid with a dissociation constant greater than 1 is considered a strong acid. Nitric acid is the weakest 'strong' acid with a Ka of 24. Considering this is all on a logarithmic scale, that is just barely a strong acid. It is about 40 times weaker than sulfuric acid, and 54,000 times weaker than hydrochloric acid, which is commercially available on the shelves at Lowes, Home Depot, etc in plastic jugs better known as muriatic acid for cleaning driveways.
pH is a measure of hydronium ions in a aqueous (water-based) solution. A dry substance or surface cannot have a pH. If it aint got water it won't have a pH...there can be some caveats to that but best to leave it there.
Therefore, a panel with acid dried onto it will have no pH unless it is made aqueous (rewet with water). If epoxy is applied to it, and as I believe epoxy is not aqueous (?), my hypothesis/theory the first time we had this conversation was it is not the pH itself that epoxy is affected by, but rather the residue of the acid on the panel which acts like a contaminant and adversely affects binding of the epoxy.
This latter point is why you can apparently get by from rewetting the acid and then rinsing off with water. Because you're simply just rinsing the residue off. But even after the residue is gone, if you were to run more water down the panel and collect it then measure the pH, it would still be very acidic. Water itself won't neutralize any acidity on a panel obviously, but like I said then and again now, my hypothesis is it's not a function of pH but residue/surface contaminant instead.
JimKueneman
Mopar Nut
Is there any side effect of using electrolysis to remove rust? Water, salt and electric current....
Jim