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Product Details
Ospho resists and retards rust while providing a sound base for paint. Recommended for use under oil base paint or primer. One gallon of Ospho covers 600 sq. feet. It dries overnight, makes a lasting bond between rusted metal and paint. (Note: Ospho is not actually a paint.) Contains phosphoric acid.
Info & Guides
Rusted Metals:
It's important to note that Ospho is a rust inhibitor coating and not paint. Before applying, use a wire brush or wire wheel to remove loose paint, rust scales, dirt, oil, and anything else accumulated on the surface. After doing this, apply a coat of Ospho and let it dry (overnight). Once the surface is dry, you can paint over it.
How does it work?
Ospho transforms rust to iron phosphate, an inert substance. You will know its doing its job when the metal turns black. This means the chemical change has occurred. Very heavy rust can require two coats. Sometimes, a dry, grayish white powdery film develops. Simply brush off before painting.Bare or New Metal:
Make sure new metal is clean and free of oils or grease before applying Ospho. After drying overnight, the surface is ready for paint.
Galvanized Metal
Treat galvanized metals differently, depending on how important appearance is. If appearance is important, apply a singe coat of Ospho and let stand for 30 minutes or until metal is etched. Flush with water or wipe to a smooth finish. Once dry, the surface is ready for paint.
If appearance doesn't matter, disregard the above. Simply apply a single coat, let dry overnight, brush off powdery residue, and paint.
Painting Over Ospho
Painting treated surfaces tends to yield more durable finishes, as moisture and oxygen are effectively sealed away from the metal. Unlike thick paints, Ospho is as thin as water, going on easily and providing much more coverage (about 600 sq ft per gallon).
This metal treatment works best with oil based paints and primers. Be sure to test before using with epoxy or latex paints. Suitable for use indoors or out.
Additional Instructions, Recommendations & Tips:
For best results, do not apply Ospho below 36 degrees F. Also, excessive moisture or humidity may cause longer drying times and increase powdery residue buildup.
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Reviews
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1 to 10 of 34 Reviews
1 – 10 of 34 Reviews
Most Recent
Linden, CA
5 out of 5 stars.
Ospho Metal Treatment Fantastic stuff
9 years ago
Pasture fence for horses, 7 acres. Easy to apply. I haven't found anything that is not so great about this product.
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West Virginia
5 out of 5 stars.
Outstanding product for rust control
9 years ago
I've been using this chemical since about 1987. I haven't found anything that comes close to matching it's performance for what it is intended. It was recommended to me by a friend that restored old cars. I needed it to control rust on the underside of a motorhome. Since then, I use it when ever I'm repairing any metal prior to finishing.
Helpful?
San Fransico Bay, California
5 out of 5 stars.
Great product
9 years ago
I have been using Ospho since 1979, while in the Coast Guard. If you have use scaly rust, brush or scrape it away. Then simply apply. Best used in direct sunlight or under an infra-red lamp. The deeper the rust, the darker the finished area. No primer needed for painting. The iron phosphate result is over 90% as strong as the original metal.
Helpful?
Rockport Tx
5 out of 5 stars.
Engine Room Touch Up
10 years ago
We live in South Texas and the Humidity is always high. It is a constant battle against rust on our engine and brackets in the engine room. We have white painted Detroit engines so the rust that forms shows up very quick. We have been using this product for years. Wether you are doing a complete paint job or just doing some light touch ups. This product stops rust in its tracks. It is excellent in preperation. It can be a little messy if your not careful. Since it has the consistancy of water, if you apply on a verticle surface it may run off. I try to get the rust off with a wire brush and light sanding. Then apply the product with a foam brush. Then allow it to work. It's that simple. I usualy give it a day, then light sand if needed and wipe clean with a rag. Then apply paint. You will notice the rust turns from a rusty red to a darker charcol or black. It is an awesome product. I would recomend to all. A little of this goes alog way.
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Australia
5 out of 5 stars.
tried the rest this is the best
11 years ago
I am a serious metal detectorist and coin hunter and for years I have been searching for the perfect cleaner for old coins that I have dug -up . after being in the ground for sometime most coins except gold get a black tarnish on them which is near to impossible to clean off . I have tried everything suggested by other detectorists and to my amazement I discovered Ospho rust converter , after soaking the coin in Ospho for only 10 mins and a vigorous scrub with a toothbrush the coin is as clean as it was new athough not as shiney , putting the coin back into circulation . badly damaged or pitted coins are beyond salvaging no matter what you do
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Baton Rouge, LA
5 out of 5 stars.
Best metal prep I have found.
12 years ago
I have been using Ospho for years and I have not found a better rust killer, paint primer yet.
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Coin, Ia.
5 out of 5 stars.
Ospho rust killer
12 years ago
I use this product for a rust killer in old cars that I restore.
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San Jose, Ca
5 out of 5 stars.
I'll be placing another order soon.
12 years ago
I restore old automobiles and this product is excellent for rust removal and metal prep.
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Gilford NH
5 out of 5 stars.
The best cleaner for steel and teak
12 years ago
I used Ospho for over 22 years of maintaining cruising sailboats in the British Virgin Islands. Absolutely the best for maintaining the engine and all steel parts, including those which stained or rusted under load. While cleaning the support frame for teak swim platform I found it cleaned the teak platform better than anything else.
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Atlanta, GA
5 out of 5 stars.
Ospho saved my old galvanized gutters
12 years ago
I am currently preparing the battery area of my sports car's engine compartment with Ospho. It is great and solves many elaborate issues that come from sanding and killing semi-invasive rust caused by battery acid. Also, about 10 years ago, I used Ospho to etch the inside of my 45 year old galvanized gutters. They had small holes in them and were very rusted. I used Ospho to kill the rust after using a wire brush, and then lined the gutters with plastic-based roof sealant and plastic mesh strips. Saved me close to $1000 for new guter sat the time and it lasted for years.
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1 – 10 of 34 Reviews
Questions
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1 - 10 of 44 Questions
Q: Can EPOXY be applied directly to metal coated with OSPHO or does it need to primed first
a year ago2 Answers
A: You can apply epoxy over metal treated with Ospho. Be sure to sand according to the specs provided by the epoxy.
a year agoHelpful?
Q: Hi, Do you ship to England? Regards, Michael
2 years ago1 Answer
A: Hey Mike, Thank You for your inquiry. Unfortunately, we do not currently have distributors located outside of the US. We do ship out of the US, but are restricted from shipping hazardous materials. Most customers shipping hazardous internationally use a freight forwarder. When using a freight forwarder it is the customer’s responsibility to make those arrangements. The freight forwarder must be able to handle hazardous materials including all documents to ship the product. We ship by US regulations to the freight forwarder either by UPS ground or truck depending on the size of the order. The freight forwarder now becomes the shipper and is responsible for any documentation for shipping. All international orders require Paypal for payment, credit card is not accepted. There is an additional 5% fee for Paypal payment.
2 years agoHelpful?
Q: Galvanized Roof treated with OSPHO what type of paint is best? and why? I have a 40+ year metal building, heavily rusted galvanized roof, ?¢??mostly?¢?? rusted. Once I have prep all panels and applied the OSPHO to the rust, what type of paint will stick best to the OSPHO and aged galvanized? I have heard oil base is not a good choice for galvanized steel, because with adequate drying time, the oil base paints can scratch off easily. One source told me to use Primer Rust Inhibitor (Primer Industrial Pro-Cryl Universal Acrylic Primer). Then on top of the primer to top coat it with DTM gloss paint (100% acrylic coating) However, any advice would be appreciated greatly. Thank you, SHandlin
12 years ago2 Answers
A: you are correct the dtm is the way to go
Anonymous4 years agoHelpful?
Q: How do you apply Ospho? Brush?
6 years ago2 Answers
A: Call Dale to discuss.
6 years agoHelpful?
Q: Is it safe to use Ospho inside a metal bread box
6 years ago1 Answer
A: If you are going to paint over it, yes.
6 years agoHelpful?
Q: I have rust around the base of my steel building (house). It is rusting around the bolts, It is only affecting the bottom row of bolts that are just a few inches above the bottom that sits on the concrete slab. Will this stop my problem ?
8 years ago1 Answer
A: TB Rust primer is a primer that will turn the iron oxide (rust!) into something good—iron phosphate—a very stable coating that prevents further corrosion. It is a primer and will need to be painted over so it will last.
8 years agoHelpful?
Q: i applied ospho to a pipe fence, it was real sticky in the beginning but it got rained on and now it's real dull looking with white residue all over. do i re apply oshpo or continue with primer?
8 years ago3 Answers
A: I have only used it on fiberglass to remove stains....works great on glass.
8 years agoHelpful?
Q: Will Ospho remove and stop rust from progressing on automotive surfaces?
9 years ago2 Answers
A: Yes ospho is best stuff on market. It stops rust and make a a great primer. I use on all metal commercial fishing boats. Works better than anything I've tried!
9 years agoHelpful?
Q: After using ospho on a cast iron pot I have several white spots. How do I remove the white crust ?
9 years ago3 Answers
A: I would try some fine steel wool and then maybe wipe the pot down with a thin coating of mineral oil or vegetable oil
9 years agoHelpful?
Q: where can you buy ospho?
9 years ago3 Answers
A: On the web
9 years agoHelpful?
1 - 10 of 44 Questions