TheSamba.com :: View topic

Sun Apr 10, 2016 10:13 am

I have the following rusted metal primers available locally:

Pettit Rustlok
Rustoleum Rusted Metal Primer
Owatrol C.I.P.
Owatrol ALU

I don't see any mention of ALU, C.I.P or Rustlok here in previous threads. The Rustlok and ALU cost about the same as Masterseries, but I'd save on shipping and the Owatrol C.I.P. has an even better price. Both Rustlok and ALU have the same high aluminum content as Masterseries, so I'm thinking they're pretty similar products with similar corrosion prevention. Any thoughts?

Thu Nov 03, 2016 5:36 pm

I have not tried any of the products in the previous post so I can't share an opinion on them. I like KleanStrip Prep and Etch myself.

Is there a thread any where that list which rust preventive/treatments have a sacrificial metal in it like zinc? It seems silly to keep going over who's marketing convinces people that they have the best moisture barrier. :roll:

Sat Dec 03, 2016 10:05 am

theKbStockpiler wrote: I have not tried any of the products in the previous post so I can't share an opinion on them. I like KleanStrip Prep and Etch myself.

Is there a thread any where that list which rust preventive/treatments have a sacrificial metal in it like zinc? It seems silly to keep going over who's marketing convinces people that they have the best moisture barrier. :roll:

Sorry...had not seen your post.

Really....everyone needs to get clear on whether a product is a rust converter, a rust remover (the difference between those is usually a difference in solution strength but there are some ingredient differences between some)....or a rust preventer....which is an encapsulate by definition.

Also bear in mind....if you already have rust......whether its crusty or thin flash rust...a rust PREVENTER/SEALANT...is 100% worthless....unless it also has an ingredient to convert that rust to a phosphate. If it has that ingredient....it WILL NOT be a useful sealant.

The exceptions to that rule...are also the most finicky and hard to use..mainly because they must have exact ambient conditions (temperature, moisture and cleanliness)....or they will cure improperly or not adhere. POR-15 and other epoxy based products that include a small amount of rust converter chemicals or acids are in this family.
If they contain too much of something like phosphoric or tannic acid....or are poorly mixed...it can cause contamination to the catalyst for the epoxy base.

The weak polymer that is included in the mixture of most rust converters like Ospho and Jasco....that causes that bluish/whitish residue....is NOT a useful sealant. It is rough, intermittent and porous. Its purpose is to TEMPORARILY protect the converted metal so you can get paint or some other sealer on it.

Ray

Tue Dec 06, 2016 3:15 pm

Well said Ray. I find the best option is always a converter, then any decent paint to seal it. You get a better version of both and much more flexibility with choice. Although nothing substitutes mechanical removal.

Related to this thread, I had a small rust hold in the hood of my pick up truck last summer. I used a knotted wire wheel to get the surface rust off, sprayed with phosphoric acid, painted with Rustoleum, and it held up perfectly after a winter of salty roads. I won't be messing with POR15 anymore.

Wed Dec 07, 2016 6:12 pm

The hood does not get direct salt spray so it does not tend to rust much anyways. You can have surface rust on the roof of a car for a few years without it getting much worse while still driving it in salted environments. This fact makes a test like that inconclusive. :cry:

On a comment to Ray's statement on the white residue of phosphoric acid: The white residue only forms on areas that have stopped absorbing or will not absorb the acid. I think it's just dried phosphoric acid actually.

I was reading on a boat forum that self etching primer has phosphoric acid and zinc in it but I did a test with it verses primer/sealer and it did not do any better against salt spray. Sounds like the perfect primer though. I put it over zinc in hopes for better adhesion. It does seem to help.

Right now after treating and or removing rust, I spay zinc cold galvanizing compound ,self etching , primer/sealer and then Rustoleum Professional for small areas of repair. The MSDS sheet for RustO primer/sealer list (Zinc Phosphate1.0-2.5 Wt.%
Range).

Salt spray is the real test. Most paints besides lacquer do okay if in a fairly dry ,salt free environment in my experience. If it gets salt spray again DIY jobs fail relatively fast,in a few years.

Mon Dec 12, 2016 7:01 pm

I did a jeep floor and used primer/sealer on 1/3rd ,RO self/etching primer on 1/3rd and only RO paint on the remainder. All areas had RO regular spay paint on top. They all rusted at about the same rate. I don't understand how RustOleums slogan is supposed to stop rust on it's own. :lol:

Sun Dec 25, 2016 7:00 pm

Thanks to raygreenwoods help and my own desperation, :lol: I have been doing some experiments.

I have three rust buckets so I have to stop fooling around. :lol:
If you use muriatic acid on a piece of rusted metal it removes rust the fastest ,BUT it loses it's ability the fastest as well. You cant' soak a section of metal and kept it moist without removing the rust/weakened muriatic mixture and then reapplying. With phosphoric acid ,you can keep the area soaked for a few days and with minimal effort scrape 95% of the rust off ,even thick scale.

I'm going to keep testing two pieces of rusted metal at the same time and the method that is the fastest between the two goes to the next round.

Mon Dec 26, 2016 5:18 pm

So, I am too lazy to read all 15 pages. What is the best Rust Prevention Product?

Sat Dec 31, 2016 7:50 am

The 15 pages goes fast.Here's another link.

http://www.thesamba.com/vw/forum/viewtopic.php?t=669622&start=0

Sat Oct 07, 2017 5:31 pm

So, the old time product for metal prep was "METAL PREP" By Dupont. Imagine that. Perhaps 5717S? They also had a product Galva Prep.
One would coat steel with the stuff, then wash it off after a while, get it well dried, then spray on your primer.
Pretty sure this was plain old phosphoric acid, 20-25%.
Where can one buy it now? I don't want anything else in with it. Not a coating, but a rinse/wash.
On ebay I can find 15gallon, 55gallon, 1275 gallon quantities from DudaDiesel. Bless their hearts. If I ever need that much, they will get my attention. Looks like they do a good job.
BUT I JUST WANT ONE GALLON RIGHT NOW. Where or how? Local would be good.
It really shouldn't cost more than $35-45/ gallon delivered.
Anybody else use this stuff?

Sun Oct 15, 2017 10:42 am

Home Centers sell phosphoric acid for about $10 a gallon. For treating I think it works better at %50 with water.

I think all the 'Paint Over Rust' product manufactures have a version,ZeroRust ,etcetera.

Sun Oct 15, 2017 3:42 pm

theKbStockpiler wrote: Home Centers sell phosphoric acid for about $10 a gallon. For treating I think it works better at %50 with water.

I think all the 'Paint Over Rust' product manufactures have a version,ZeroRust ,etcetera.
"Home Centers" is a local chain?
Al

Sun Oct 15, 2017 4:47 pm

http://www.homedepot.com/p/Klean-Strip-1-gal-Phosphoric-Prep-and-Etch-GKPA30220/1004063

Tue Jan 09, 2018 5:55 pm

I dumped the gate latches from my double cab into a 5 gal bucket with 4 inches of plain white vinegar. They were pretty crusty. After 4 days i brushed them off with a wire brush. Let sit for another week and brushed them off again. The vinegar removed all the rust and left what was left of the original paint.
So i dumped and added more vinegar and dropped a bunch of old rusted wrenches I had saved. after 10 days I brushed them off, dried and rubbed marvol mystery oil on them and they look fantastic. Not like brand new but super nice. The vinegar will turn everything black, you just need to brush/rinse/brush til the metal comes thru. Its not quick but its low on the labor scale.

Mon Jan 15, 2018 6:39 pm

If it is submersible I use Evaporust. As an example, the galvanized bars in my roof rack on my '71 Bay bus had worn through the galvanizing and were growing surface rust. I found a polyethylene toy sled that was long enough to accommodate the bars and poured in enough Evaporust to submerge them and let them sit for a day. The Evaporust removed the rust and and turned the steel a grayish color. I pulled them out and rinsed them with water and quickly dried them. After that I sprayed them with Rustoleum cold galvanizing spray and didn't expect much from it. It does have a high Zinc content. I was amazed that after the first coat that it looked and felt very much like hot galvanizing. I gave it 3 coats and they look like new. the Evaporust is about 27 bucks a gallon. It is a rust remover. I also have used an Ospho type converter called Oxygone. it is cheaper than Ospho and seems to work pretty well.

Thu Jan 25, 2018 6:42 pm

I was using a mix of 70% phosphoric acid to 30% muriatic( I found this ratio works the best usually) but I tried vinegar instead of the muriatic. It worked about as good and does not evaporate so there is less danger of breathing the fumes. :shock: I don't think muriatic acid works that well on it's own and gives off a lot of fumes making it a big hassle. Muriatic acid does not seem to be able to penetrate the surface at all where as phosphoric will. Vinegar is a lot cheaper at about 15% the cost. I'm going to try to do a mix of 70% ,15% and 15% for a while. :D

Sat Feb 03, 2018 10:54 pm

:D
I recently discovered that powdered laundry detergent completely stops flash rusting. First rinse and brush with water ,then soak if you can, and or brush on 1/4 cup of the detergent to 1 gallon of water for a few minutes and then rinse again with water. :D

Wed Mar 21, 2018 8:12 pm

My rust removing adventure continues. If acid stops being effective on a piece you're working on, wash it with the detergent I previously mentioned and let it thoroughly dry. The rust will then act like a sponge and absorb the acid and be effective again.

Thu Mar 22, 2018 4:31 am

theKbStockpiler wrote: :D
I recently discovered that powdered laundry detergent completely stops flash rusting. First rinse and brush with water ,then soak if you can, and or brush on 1/4 cup of the detergent to 1 gallon of water for a few minutes and then rinse again with water. :D What brand detergent are you using? I am curious to know what ingredients are involved.

Thu Mar 22, 2018 4:54 am

I have been doing something similar to "theKbStockpiler."

For submersible parts my process is:
- Wire brush heavy rust
- Soak in vinegar for several days
- Wire brush to remove rust residue, rinse in 50/50 water/antifreeze, repeat until clean
- Soak in Eastwood After Blast for 12 - 24 Hrs
- Wipe dry, wet with After Blast, repeat until clean

For non-submersible parts my process is:
- Media blast with crushed glass
- Wet with After Blast, wipe dry, repeat until clean

The Eastwood After Blast appears to be doing a good job of keeping the parts rust free. As an experiment I wiped one part with a wet towel and left to air dry, and handled another part with bare hands (natural body oil present.) Neither part is showing signs of surface rust.

...We're all in this together,
Emil