camo.b
Member
Easy job then...very nice! That link you posted..that gun looks the goods.just make sure you get a 360°nozzle for the paint also.
chassis rust
- Thread starter JLA
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JLA
Member
The following is a very different approach to previously discussed.
Today I spoke with a local distributor of the por15 system.
The normal process is:
1/ Marine clean to remove contaminants.
2/ Rust converter
3/ POR15 - coats
4/ Top coat
BUT
Inside a chassis is confined and it's critical that you get it right.
You cannot afford to have rust going on under the paint.
Applying a system to inside a chassis is different to repainting a battery tray.
It seems like all rust converters are mainly phosphoric acid.
The rust converter fixes the rust that you can see but it does not prevent new rust from forming.
Also it is impossible to remove all traces of the acid and "acid etching" also contributes to further corrosion.
The POR15 overcoats the rust converter and prevents further rust by keeping out moisture.
All that works fine where you can easily access the job.
The POR15 needs to be applied in two "thin" coats.
If a thick coat of POR15 is applied then many pinholes appear in the paint that allow moisture to pass through the POR15 to the metal.
It is not possible to correctly apply the POR15 paint inside a chassis without having this effect due to the access difficulty.
Marine clean:
This product is used to clean contaminants/salts etc that may otherwise cause corrosion.
The product is slightly alkaline and does not contribute to corrosion itself.
Wash it off as per the directions and dry before the next process.
Rust converter:
It seems metal treated ONLY with rust converter will look OK for a short time but then corrode faster than if the rust converter was not used.
Needs to be thoroughly cleaned off once converted and then over coated with another product to exclude moisture.
Would be high risk to use inside a chassis as it cannot be effectively cleaned once converted and also the overcoat cannot be controlled.
May create corrosion that would be uncontrollable.
POR15:
Not suitable for inside a chassis, fine for outside where coat thickness can be observed and defects remedied.
Dynax S50 Cavity wax:
Provides a wax barrier to prevent moisture from contacting the metal.
May attract dust etc. but might be OK as well?
SW2:
This product is a synthetic fishoil. Unlike organic fishoil this product does not break down.
It dries to a hard shell and is not sticky like its organic version.
It can be applied with a household squirt bottle with an add on tube with a 360 degree spray micro irrigation fitting on the end of the tube.
Applied from both directions should give 100% coverage.
Could use a kero gun and mist it through from both ends but not without making a major mess.
THE NEW RECOMMENDATION:
1/ Use Marine Clean to remove salt/contaminants. (May not be essential in all cases).
2/ Wash with water and allow to dry. Must be very dry. This means days later or possible forced hot air drying in the chassis rails.
3/ When all moisture has dried out, apply a generous coat of SW2
You have not added any corrosive products.
You can monitor rectify if treatment is required years later.
I would be interested in any comments anyone has.
Today I spoke with a local distributor of the por15 system.
The normal process is:
1/ Marine clean to remove contaminants.
2/ Rust converter
3/ POR15 - coats
4/ Top coat
BUT
Inside a chassis is confined and it's critical that you get it right.
You cannot afford to have rust going on under the paint.
Applying a system to inside a chassis is different to repainting a battery tray.
It seems like all rust converters are mainly phosphoric acid.
The rust converter fixes the rust that you can see but it does not prevent new rust from forming.
Also it is impossible to remove all traces of the acid and "acid etching" also contributes to further corrosion.
The POR15 overcoats the rust converter and prevents further rust by keeping out moisture.
All that works fine where you can easily access the job.
The POR15 needs to be applied in two "thin" coats.
If a thick coat of POR15 is applied then many pinholes appear in the paint that allow moisture to pass through the POR15 to the metal.
It is not possible to correctly apply the POR15 paint inside a chassis without having this effect due to the access difficulty.
Marine clean:
This product is used to clean contaminants/salts etc that may otherwise cause corrosion.
The product is slightly alkaline and does not contribute to corrosion itself.
Wash it off as per the directions and dry before the next process.
Rust converter:
It seems metal treated ONLY with rust converter will look OK for a short time but then corrode faster than if the rust converter was not used.
Needs to be thoroughly cleaned off once converted and then over coated with another product to exclude moisture.
Would be high risk to use inside a chassis as it cannot be effectively cleaned once converted and also the overcoat cannot be controlled.
May create corrosion that would be uncontrollable.
POR15:
Not suitable for inside a chassis, fine for outside where coat thickness can be observed and defects remedied.
Dynax S50 Cavity wax:
Provides a wax barrier to prevent moisture from contacting the metal.
May attract dust etc. but might be OK as well?
SW2:
This product is a synthetic fishoil. Unlike organic fishoil this product does not break down.
It dries to a hard shell and is not sticky like its organic version.
It can be applied with a household squirt bottle with an add on tube with a 360 degree spray micro irrigation fitting on the end of the tube.
Applied from both directions should give 100% coverage.
Could use a kero gun and mist it through from both ends but not without making a major mess.
THE NEW RECOMMENDATION:
1/ Use Marine Clean to remove salt/contaminants. (May not be essential in all cases).
2/ Wash with water and allow to dry. Must be very dry. This means days later or possible forced hot air drying in the chassis rails.
3/ When all moisture has dried out, apply a generous coat of SW2
You have not added any corrosive products.
You can monitor rectify if treatment is required years later.
I would be interested in any comments anyone has.
dirtjockey
Member
I agree with this based on my experience - POR15 seems to rely on having a complete seal - any gaps and rust gets in underneath it and it actually seems to rust a whole lot worse - their literature talks about some sort of chemical reaction and this in turn prevents any further rust - what a crock of sh!t - I've got plenty of photos of (badly) rusted steel that's been POR15 coated - we've looked at all sorts of options and far and away the best seems to be fish oil - then once it's close to dry (which can take a week or more) we wipe it with metho and get all the heavy Glunky crap off and you end up with a nice clean coating which goes for years without deteriorating. Of course this is not something that you can do inside a chassis rail. Once the rust has set in (inside a chassis) - it's going to be very tough to get rid of it. IMO
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If it were mine I would drench it in diesel, let it dry, takes a week then hit it with fish oil. Apply fish oil each year. That way any emerging rust will be covered.
I've been using this method on a rusty trailer for years, as long as you repeat regularly it works great.
Penitrol is another way to go. It actually penetrates the metal and seals it off. You could repeat a coat regular as well.
There is no way IMO to get 100%.
I've been using this method on a rusty trailer for years, as long as you repeat regularly it works great.
Penitrol is another way to go. It actually penetrates the metal and seals it off. You could repeat a coat regular as well.
There is no way IMO to get 100%.
JLA
Member
Its interesting that this discussion is going back to the old tried and tested fish oil solution that has been successfully used for 40 years that I recall and probably much longer. I have rust proofed two of my own cars over the years with fish oil and no rust issues. One car I drove for 25 years and another for 15. There were a few dings in panels at the end but no rust.
SW2 is supposed to be "synthetic fish oil". Where organic fish oil stays sticky, the SW2 dries hard which means dirt and sand does not stick to it. I wonder if SW2 is as effective as organic fish oil in preventing rust? If so then SW2 would be a better solution.
Probably there are a few products that would do the job; SW2, fish oil, penetrol, cavity wax etc. and as was stated these may have to be monitored and reapplied if required. A positive characteristic of these products is that they do not contribute to corrosion as rust converter does.
Not sure why the suggestion of flooding with diesel initially and then fish oil? As diesel is basically kero + oil mix I suppose some oil would get into the tiniest cracks first?
SW2 is supposed to be "synthetic fish oil". Where organic fish oil stays sticky, the SW2 dries hard which means dirt and sand does not stick to it. I wonder if SW2 is as effective as organic fish oil in preventing rust? If so then SW2 would be a better solution.
Probably there are a few products that would do the job; SW2, fish oil, penetrol, cavity wax etc. and as was stated these may have to be monitored and reapplied if required. A positive characteristic of these products is that they do not contribute to corrosion as rust converter does.
Not sure why the suggestion of flooding with diesel initially and then fish oil? As diesel is basically kero + oil mix I suppose some oil would get into the tiniest cracks first?
This is a really interesting threat. My 06 d22 has some fairly severe rust problems which ive grinded back and painted or repkaced parts as I work on it.
The main worry is definitely the chassis rails though. Woukd be interested to see how much this treatment will actually cost you in the end
The main worry is definitely the chassis rails though. Woukd be interested to see how much this treatment will actually cost you in the end
camo.b
Member
Very interesting info JLA about the por15 not reccomended for internal use.must day ive never seen a rust stripper/converter that i have left on,normally on purpose continue to rust the area.but most times ive left it on somthing like a body panel.i find it normally gets a nice zink look to it then i get back to it then rework the area anyway..somtimes this can be 6 months...but ive never painted the area without a full clean
Yeah the diesel will creep into places, under lifting paint, and penetrate the metal. It works fine on its own but drys and washes off, so very regular application would be needed.
SW2 sounds great, especially if it penetrates. Fish oil will likely wash out in time.
Hard to find peace of mind on this issue I'm sure.
JLA
Member
Hasleby: I'm not so worried about the cost of this process considering what is at stake. DIY with Marine wash and SW2 would cost less than $100. If I could get a rust guy who knew his stuff and did the process correctly then I would gladly pay $1,000.
Problem is there are some rust guys who will say "Yeh mate we can fix that", charge a few hundred and effectively write off your vehicle by their choice of products and processes.
The only way is to either know/trust someone or DIY with a proven process.
I know I am flogging this post a bit but I am trying to flush out people's experiences, they are of high value.
Problem is there are some rust guys who will say "Yeh mate we can fix that", charge a few hundred and effectively write off your vehicle by their choice of products and processes.
The only way is to either know/trust someone or DIY with a proven process.
I know I am flogging this post a bit but I am trying to flush out people's experiences, they are of high value.
JLA
Member
Seems like rust converters consist of Tannic Acid that converts the rust and a wetting agent. Some rust converters also contain phosphoric acid as well.
The question is, is one better than the other inside chassis rails?
Is one more or less likely to reduce the ongoing rust problem than the other?
Another reference suggests the biggest disadvantage is when the rust converter has trapped water vapour, saying this is when rust converters fail.
This would suggest that the metal must be bone dry before rust converter is applied.
Many articles state that after the rust conversion the metal needs to be protected by an overcoat product to prevent moisture restarting the rust.
Apparently rust converters are not permitted in many areas of steel construction.
The question is, is one better than the other inside chassis rails?
Is one more or less likely to reduce the ongoing rust problem than the other?
Another reference suggests the biggest disadvantage is when the rust converter has trapped water vapour, saying this is when rust converters fail.
This would suggest that the metal must be bone dry before rust converter is applied.
Many articles state that after the rust conversion the metal needs to be protected by an overcoat product to prevent moisture restarting the rust.
Apparently rust converters are not permitted in many areas of steel construction.
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