I see many ibles made with black pipe here but rarely do they mention any coatings to prevent rusting. I also often build with rusty items where I need to cover the rust so it won't rub of on clothes etc. but don't want to lose the beauty of the patina. An architect once told me he used linseed oil to preserve rusted iron outdoors. I tried it but the damned stuff never fully dries! I could use polyurethane but the oxidation will continue underneath and it will eventually flake off. I've tried "rust stabilizers" but they turn the rust black so it loses it's color. I finally got turned on to a product from an old timer in a paint store I would probably never have found on my own.

Step 1: Penetrol

He recommended a product called Penetrol normally used as a paint additive to improve flow and adhesion that also seals and stops rust. It can be used alone as a base coat on bare metal and will fix the rust while preserving the appearance. The finish will be darker than dry rust but similar to rust sprayed with water or oil and can be top coated with a polyurethane for a more durable finish.


Be sure to open and view the rest of this ible before sending me questions. ;-)

Step 2: Obey the Bot

(I originally made this a single page post since it's basically just a product recommendation but "the Bot" didn't like that. It yanked the post and sent me a note to mend my ways. So... I chopped it up and added some numbered steps. Hope it stays put this time. ;-)

1) I usually wipe down the piece with paint thinner to remove excess dirt and oil but since the product is oil based you don't need to remove every last trace. For a rusty surface I'll usually clean it real good with water and a soft brush or cloth to get any dirt off. In the case of the steel vanity tops shown in the intro I left one out in the rain for a week to cover some scratches and wanted to preserve the light layer of rust. I just rinsed it off with a hose on saw horses, let it dry in the sun then

2) applied the Penetrol with a brush. Even on the perfectly flat surface it didn't leave brush marks.

3) I always spray on a mat polyurethane top coat or two for a smooth finish and the finished piece looks completely natural.

I've used this method for several years now including on towel bars hung with damp towels everyday and for a countertop under my bathroom sink. So far they look just like the day I finished on all my projects.

Step 3: Answers to FAQs

The reason I use the polyurethane top coat(s) is that the Penetrol is a linseed oil product, and as such, is not very hard or durable. The polyurethane is a good, stable, long-lasting finish that won't easily wear off.

I've also been getting a lot of questions about clear, un-rusted metal. I wrote this about protecting and preserving the rust for it's looks. But if you don't have rust, you can skip the penetrol and just go straight to the polyurethane.


I'm just a guy who, by chatting with an old time paint guy, stumbled onto a way to stabilize and preserve rust without hiding it. please don't ask me how to repaint your car or patio furniture. I don't know. This post is only about preserving the beauty of rust while stabilizing it to make a rusty object useable and not so messy.

A table top, specially a work table or dinning table, is a pretty tough environment. It's prone to lots of impacts and abrasion. At the least, you should use several coats of polyurethane. You might also talk to someone at a Sherwin Williams store about SherClear. It's a HD industrial clear coating. It's pricey ($100/gal?) but incredibly tough. It's made for ships and equipment but a friend uses it to coat canvas floorcloths and says it lasts for years in high traffic areas and under tables and chairs.


If you already have an oil base coat like Penetrol, you can only use an oil based product on top of it. Remember that oil floats on water. You can use oil OVER an water based coating but not the other way around. The reason is that oil based coatings don't set up completely hard but remain somewhat flexible. Water based products set up hard and inflexible and will eventually flake and peel on top of oil based coatings.

<p>would this work on cast iron radiators? about to have mine sand blasted clean and didn't want to paint them because i like the raw iron look. we run them at lower temp 140 - 150 degrees.</p>
I would think so but as I've said many times, I'm not a paint specialist. In the grand scheme of things, anything under the boiling point of water isn't really all that hot but you should check with a good paint store about the appropriateness of any coatings for higher temps that could promote of gassing.
<p>thanks for the reply!</p>
Could you give me a call mate, got a few questions and was thinking you might be able to help me out- 0452516119
<p>Hi Brian et al,</p><p>I want to install a galvanized steel shelf as a kitchen/breakfast bar in my home (between kitchen and dining room--the stove is on the opposite wall so it would not be affected by direct heat). Would the penetrol stop the sheet from rusting? I am more interested in preventing rust than in preserving it. </p><p>Thank you!</p>
<p>Sorry, not galvanized steel--hot rolled steel.</p>
If no rust has started, any coating will work but it should be tough for a countertop. You could also use paste wax but it should be reapplied once or twice a year. For a clear coat, look into Sher-Clear from Sherwin Williams.
<p>I want to preserve rusty mild steel laser cut sheets on my fence, do I only apply one coat of penetrol or more?</p>
<p>Great article Brian!</p><p>I have this rusty fireplace which I plan to sit on natural stone pavers in my pool area. I obviously don't want it to run and stain my pavers when it gets wet. I plan to give it a good soaking to remove all the excess then seal/coat it. Given this and considering the high temps, would Penetrol still be effective?</p><p>Or could a high temp automotive clear spray also be a good option?</p><p>TIA</p>
I wouldn't think the penetrol would work with the heat. I'd check with a paint specialist like Sherwin Williams to see what they say. Then report back hear and enlighten the rest of us!
<p>new link...</p><p><a href="https://www.flood.com/products/paint-additives/penetrol-oil-based-paint-additive" rel="nofollow">https://www.flood.com/products/paint-additives/pen...</a></p>
<p>FYI, you can intentionally create a beautiful orange-y fully rusted surface, which itself will stop further rusting. &quot;Cor-Ten&quot; is a brand, used in bridges, etc.</p><p><a href="https://www.instructables.com/id/Produce-a-Rich-Rust-Patina-on-Iron-and-Steel-Safe/" rel="nofollow">https://www.instructables.com/id/Produce-a-Rich-Rus...</a></p>
<p>Hello,</p><p>I have a steel fence and would like to preserve the rust patina, and stop more rust from occurring. It is outside. We do not want a shiny finish or for it to stain when touching it. Do you still recommend the Penetrol with another finish over it? We really love the look and want to preserve it, but are very worried with the deterioration of the steel bars, they surround a cliff.</p>
<p>Hi Brian,</p><p>I have made a rusted indoor stairway for a customer. I'm thinking of using Penerol and poly as protection. Do you know if Owatrol is the same as penerol or can be used in the same way?</p><p>https://www.amazon.co.uk/Owatrol-rustol-owatrol-Rust-Paint-Additive/dp/B007NH3G0O/ref=pd_sim_sbs_60_6?ie=UTF8&amp;dpID=517Lxm5RoqL&amp;dpSrc=sims&amp;preST=_AC_UL160_SR100%2C160_&amp;psc=1&amp;refRID=JQNM3Y979TRD0FF4AJJF</p>
I'm not sure but it sounds pretty similar. Call the manufacturer or test it on something rusty. Then come back here and post a picture. We'd love to see it.
<p>In fact, they are the exact same product. &quot;In some countries Penetrol is known as OWATROL.&quot; &mdash; http://www.floodaustralia.net/brochures_guides/pdf_files/Penetrol-brochure.pdf</p>
<p>you are a life saver. Ordered today. Will post pictures when I have them. </p>
<p>I redid my park bench with Pentetrol to preserve the rust on the iron surface. I was going to put spar urethane on it as a top coating instead of polyurethane since it is for outdoor use. It says it's used for wood but I was wondering if iron is okay and if anyone has tried this?</p>
We want to put old galvanized steel on the ceiling and halfway up the walls (48&quot;) of our lake cabin. How should the steel be prepared prior to installing? I do want the old look, rust and all.
This technique would be perfect for your project. If there's any chance of condensation, do both sides.
I want to polish an old cast iron pulley without removing the patina. Will penetrol work for that. Pic on left is what i want to achieve .Right is what im starting with. <br>Thanks <br>Dana
<p>If you dipped the one on the right in water, that's pretty much what it would look like after a coat of penetrol. The one on the left has the rust removed, not preserved. Try Naval Jelly or some other rust REMOVER to get down to the bare metal. The trick will be keeping the rust from returning without seizing up the pull wheel. You could use paste wax but it will be tricky to buff out on those inside surfaces. Penetrol might work if you don't get too much inside the pulley hub.</p>
Thank you Brian. Maybe the one on the left is painted then. Because ive buffed these down to bare metal before and they're shiney silver. Which dont like. . And i was looking on the web for where to buy penetrol. It seems there are several penetrol products. Which on is the one you use?
<p>You're on your own there, I've only see one kind of Penetrol. </p>
<p>I already applied limseed oil, yup,doesn't dry. Now what? Try to rub off and uses penetrol? Thanks</p>
<p>pale boiled linseed oil has drying agents, like terebine, in the formula. You could try just coating again with pale boiled linseed oil over your plain linseed oil coat..it should dry ok then.</p>
Don't know, not a paint guy. I'd check with a knowledgeable person at a paint store or Google around 'til I thought I'd found a good answer. When you figure it out, please post back here. There will be others that would be glad to know the answer.
<p>Hey Brian. So Im building a wine tasting area with an industrial look to it. Decided to go with hot rolled steel sheets for flooring. Id like to preserve the rusty look and I see you recommended Penetrol. Now if I go with Polyurethane on top of that, how slippery would it be? Do you have any other recommendations for the top coat thats not slippery?</p><p>Thanks</p><p>Aman</p>
<p>What great information and helpful advice to those of us that love the rustic patina look. Thank you all for sharing and advising.</p><p>I also have a question regarding some inexpensive oil lanterns that I purchased off Amazon earlier this year. I opted for the uncoated sheet metal lanterns so that I could get them to rust, which they have marvelously. Now, I'd like to seal them to stop any further rusting, but also to maintain the existing look I have. It's a little tricky, becuase these lanterns will be used and stay out in the elements year round. The work great because rain does not get into the burner area so the wick stays dry. Would your recommendation work in my circumstance, or would the heat be a problem? I could get by with only treating the oil tank area, which would not produce heat, but I'd love to treat the entire exterior. Any thoughts or advice?</p>
<p>Brian, I will be using welded wire fencing for deck railing and want it to rust for color but then coat to keep it off hands and such. What do you recommend? Anything besides the SW Industrial Poly you know of? Here is a pic I borrowed off Google showing my intention, but this is Galvanized I don't want the silver look. thx, Mark</p>
<p>For outdoors, I would probably stick to the Penetrol and not use any polyurethane top coat. The Penetrol won't crack and peel as it ages in the sun like poly and can be reapplied without all the scraping and sanding if it needs it. </p>
<p>Thanks for the reply. I guess what confused me was a comment someone made that said Penetrol will not fully dry/cure. </p>
<p>Hi Brian, my wife bought a used Bourbon barrel with the intent of using it as an accent piece in our living room. The metal bands have some rust and I want to preserve the look. I stumbled upon this very helpful topic and have read through the comments, and I have a few follow-up questions:</p><p>1) The Penetrol instructions say &quot;for exterior use only&quot;, which has me a little concerned about the toxicity. If I am using it for an indoor piece, how long should it cure and dry before moving inside?</p><p>2) Will the Penetrol prevent the transfer of rust to hands and clothing, or will I still need to apply a coat of something else on top of the Penetrol?</p><p>3) You mention Penetrol is not very hard or durable. Since this will be an accent piece and rarely touched, do you still think a polyurethane coat is necessary?</p><p>4) Can I apply the Penetrol to the entire oak barrel, or should I mask it and apply only to the metal?</p><p>Thank you in advance!</p>
1) You'll have to check with the manufacturer on this. I don't recall seeing that warning before. I would think a polyurethane top coat would be sufficient to encapsulate it.<br>2 &amp; 3) Yes. &amp; It's a good idea. The Penetrol isn't a good final finish and the Poly is easy to apply. It will take more time to clean the brush than to put a coat or two on the bands.<br>4) There's no reason to put Penetrol on the wood but the Poly would work well and make the wood easier to keep clean.
<p>Thank you for sharing this product and information about it, especially that it is linseed oil based, which is not mentioned on their WEB site, literature, or the MSDS. I noticed that you added Step 2, as an after thought, for the Bot. I don't know when you added Step 3 but, I hope it works as you intended ;)</p>
Thank you Arnold. It's good to hear from you. I miss the show. Glad to see you haven't been mad into bacon yet. ;-)
I don't recall where I heard it was linseed oil based, so if none of the companies data says so, don't take it as gospel. That said, it makes sense, and it feels like it is, but I don't have any direct knowledge.<br><br>As for step 3, not really, but it did make me feel better at the time. ;-)<br>
<p>It takes someone like you with experience to understand what is there. About 32% of this product is a secret. The company is only required to mention the hazardous ingredient(s), and their percentage, through a MSDS. Roughly 68% of this product is some form of thinner and/or drying agent. This would explain why you don't have the same problem(s) previously experienced with the linseed oil drying/curing time and how it gets &quot;under the rust&quot; to stop further oxidation, while preserving the surface rust. Again, thank you for sharing this, your experience and time on this site. </p>
<p>Hi, I have a gorgeous old cast iron soap dish that I want to hang in my new walk in shower (I guess I'll have to screw it into the walls once they're tiled). Do you think this process will be enough to handle this kind of wet environment? I love the old patina, but my boyfriend will cement me behind the walls if it ends up rusting over all our new tiles. Thanks for the help and advice.</p>
<p>Nope. Don't do it.<br><br>It's not the water so much as the soap. I don't know why, but no coatings I know of will stand up to soap for long. Even the baked on epoxy paints they use to &quot;refinish&quot; old sinks and tubs will only last a few months unless the user is really over the top OCD about <strong><em>never</em></strong> letting any soap sit on the finish. If it is enamel over cast iron, you might be able to find someone doing re-enameling but they are very hard to find these days. True enamel is a fired on glass powder. DO NOT let anyone convince you that their spray on epoxy coating will work. If it was originally chrome plated, you can probably find a plater in your area who can re-plate it for you.</p>
I installed in my yard a metal goat sculpture that has been painted white. It has some small patches of rust here and there, which I want to keep--since they make the goat look more realistic. But I don't want the whole thing to rust. I love how it looks now--and want to keep it just as it is: mostly painted with a few rust spots. It'll be outside in the elements except winter). Can I achieve this?
<p>The Penetrol would stop the rust but I'm not sure if it's clear enough to put over white paint. I'd test it on something white first to see what you think.</p>
Hi Brian, <br><br>I've got some cold rolled steel table tops in a restaurant. Having difficulty keeping a finish on them as they are in everyday use, I've used a couple of different polyurethane finishes but always scratch and flake off. Any suggestions? Needs to be 100% food safe. Thanks
You might try waxing them. It would't flake but also wouldn't be scratch resistant and you might need to re-wax them occasionally but it would protect from the moisture of frequently wiping them down. What do you do now when they start to flake?
I just got a large metal planter that I have out rusting right now. I want the rust finish to stay but I'm concerned that the rust will run off and stain the surface it will be on. Will Penetrol solve this problem? And will Penetrol be all I need or should I use polyurethane as well?
<p>If it's inside I'd coat it with the polyurethane. It 's a harder surface and much easier to keep clean. If it's outside, I'm not sure. My instinct would be to not add the poly because the UV might cause it to peel eventually but I'd check with a good paint store to be sure. None of my stuff is outside so I haven't researched for those conditions.</p>
It will be outside. Will the Penetrol keep the rust from running off with rain?
<p>If it's well sealed it I would think it should but like I said, I'm not sure about outside applications. You may have to recite it periodically. Check with an expert at a real paint store, not a big box or local hardware store. You may also check with the manufacturer on their web site or tech support. <br></p><p>When you find out, post it here so others can benefit too.</p>
<p>For those with metal and iron they want to protect from rusting, look at Corrosion X. It isn't anything like Penetrol, so isn't ideal for the artistic applications, but it is remarkable for protecting that cabinet saw top and so forth.<br><br>I polished my cabinet saw top using worn diamond pads from my granite polishing adventures. When done, I had a mirror like surface. It was wonderful, but needed protection. I'm not fond of wax and such, because it just doesn't hold up and even a drop of sweat can leave evidence you were working. Corrosion X gave the table top long term protection. The sad thing was, it also hid the mirror finish.</p>

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