Using Evapo-Rust chelating agent to remove rust from porcelain signs

[rfkimba]

Hi Sign Collectors,
Most old porcelain signs have some degree of rust which I find offensive. I use the above product which literally puts the  rust into solution while reserving the solid metal and porcelain. Areas of porcelain loss are still evident but just not covered with ugly rust. It also works well for derusting old screws, and tools.
Is there any harm to the signs value by doing this?
Thoughts?
Bob Farber
ATCA, TCI

[TelePlay]

I have  gallon of it and use it occasionaly on phone parts. Never had much success with it in that I was expecting it to work faster. Hard to find and MSDS sheet saying what the active ingredient is but I did find this usage paragraph:

How does Evapo-Rust® work?

"EVAPO-RUST® works through selective chelation. This is a process in which a large synthetic molecule forms a bond with metals and holds them in solution. Most chelating agents bind many different metals. The active ingredient in EVAPO-RUST® bonds to iron exclusively. It can remove iron from iron oxide, but is too weak to remove iron from steel because the iron is held much more strongly."

From that, it works the same way molasses does on rusted steel lanterns by chelating the the iron out of iron oxice (rust) but was interesting to note that Evapo-Rust only works on rusted iron and not rusted steel (lanterns are made of steel so it would not work for them while it would work for the iron flanges of signs).

Same principle thought, the chemical, whatever it is, grabs onto the iron in the iron oxide rust leaving an oxide that is easily washed away. The byproducts of Evapo-Rust, besides the muddy reddish brown crud, are oxides of carbon (carbon monoxide and carbon dioxide) unlike molasses which releases oxygen, IIRC, when the sugars in molasses do their chelating.

I did find that it is is highly reactive with any oxidizing agents or strong acids which make sense in that those items which would cause rust would react quickly with the organic salts which are the working ingredients of Evapo-Rust.

Evapo-Rust works a bit like naval jelly (phosphoric acid) in that it leaves a coating on the metal which keeps rust from forming for they say up to 4 weeks. The difference is that Naval Jelly does not remove the rust, it just changes it to a mineral form of iron (a rock like substance) which keeps rust from reforming, protects the surface, and allows the iron phosphate to be directly painted over (automobile  and aircraft carrier type uses usually). Naval Jelly does not remove the iron oxide, it converts it to a mineral like form of iron that is quite hard, stable, dark colored and paintable.

I've never had an iron flanged sign to practice on but I am thinking a thin coat of Naval Jelly applied with a cotton ball after the Evapo-Rust treatment might do wonders to convert any rust still in pitted areas to iron phosphate and then whatever surface top coat applied (If not being painted, I really like 25% boiled linseed oil in 75% mineral spirits for the top coat, as many coats as it takes to just get to feeling gummy) before top buffing with 0000 steel wool and then a thin layer of that wonderful creation, Renaissance Wax to protect the surface).

I'm not sure how Evapo-Rust would react to tin, it is stated as :"safe and proven effective to remove even deep rust on all types of mild steel and iron. It is safe on all surfaces and will not harm copper, brass, aluminum, plastic, rubber or vinyl. EVAPO-RUST is non-toxic, non-corrosive, biodegradable and contains no acids or alkalis. It is non-flammable and contains no petroleum solvents." Also, the cost of 5 gallons to submerge a full sized rusted lantern is cost prohibitive for my budget compared to molasses.

A chart showing it's use against more drastic measures is attached. I would say the Evapo-Rust column would also be the same for molasses but for different metal applications.

Some before and after photos of you work with Evapo-Rust would be interesting to see how well it works at removing rust and preserving the metal underneath it.

[rfkimba]

Hi John,
Attached are before and after photos of a 1908 Pay station I recently   purchased from John Huckeyby that was listed in the September ATCA newsletter. The pre Evapo-Rust photos are cloudy and washed out courtesy of John Huckeby and the after ones are of it resting on my sign soffit in my man cave game room. The significant rust on the flange was removed easily by the product.

My question I am putting to sign collectors is does gently removing rust affect the signs value? I do not   coat my signs after cleanup as my basement is dry.
Any thoughts?
Sincerely,
Bob Farber

[Sargeguy]

I do not think it really affects the value.  The rust will return eventually anyway.  If it removes rust stains on the porcelain that should enhance the value.

[TelePlay]

I've had very good success at coating the exposed rust removed metal with Naval Jelly (wipe it on with a cotton patch, let site for an hour and wipe it gently with a damp cotton cloth to remove non-reacted jelly. The Naval Jelly will turn the metal and any remaining rust a dark grey to black which to me always looks better than the cleaned metal.

I then put a light coat of RenWax all over the item. I am a very, very strong believer in this wax I found some time ago when looking for a wax to cover bare polished metal.

     http://www.ebay.com/itm/Renaissance-Wax-Micro-Crystalline-Polish-Large-Size-200ml-Tin-7-fl-oz/181530240919

This is going to sound like a paid ad for the stuff but it's not. I use it on everything except plastic and am amazed by it every time. All of my tin plate lanterns get a coat (on top of the naval jelly and then the boiled linseed oil) before taking after photos.

It's not cheap but a little goes a long way. After a year, I still haven't used more than 20% of my first can and I use it on everything. Thousands of cans have been sold and $22.50 with free shipping is quite a deal considering what you then have to protect surfaces.

It's a non-acidic micro-crystaline petroleum based wax (plant based waxes have organic acids in them that hard the surface over time)  that does nothing more than place a very thin protective coating on the surface. I put it on with a small cotton patch and as soon as the item is covered, I wipe the entire surface with a micro-fiber cloth. On fresh baked paint, it takes away the gummy feeling. On lanterns, it makes the boiled linseed oil top coat smooth.

No need to wait for it to dry, does not create a film, does not need buffing and does not need a second coat. Just wipe it on and wipe off the excess.

One coat lasts many years. That's why it was developed, to preserve paintings and metal work on pieces in major museums. I think it would be a great protectorant on the bare, naval jelly treated metal of porcelain signs. Would also protect the porcelain should there be any micro holes in it exposing the under lying metal. Naval Jelly is a phosphate based liquid that converts iron and rust to a mineral, a rock, that prevent future rusting and protects the converted surface from moisture.

The wax does not change the appearance of the surface. After using it, the surface will look the same. It does not get more shiny or more dull or change color. It just preserves and/or protects the surface from ambient moisture and whatever else is in the air. The surface looks the same after applying as it did before application.

Not sure if any other member has taken me up on my advice and use the stuff but I swear by it. I coated that polished metal 302 housing months ago and it has not tarnished since. Looks the same as it did when I took this photo and it sits on my desk, uncovered, every day. This is a highly polished bare metal with nothing on it but a coat of RenWax.



This is all in my opinion after use and if anyone else has tried this wax, please post your observations here. Not the first time I've offered this advice and after buying and trying over a dozen waxes for bare metal, settled on RenWax.

[cihensley@aol.com]

John:

I agree. Excellent wax.

Chuck

[Sargeguy]

I've used Ren-Wax to improve the appearance and prevent the spread of horn silver and bronze disease in my ancient coin collection.  I have also used it on hard rubber parts like receivers that have discolored.  It is a great product.

[rfkimba]

Hi All,
Howard's Feed N Wax which I use on wood usually after Howard's Restore A Finish cannot be substituted for Renaissance  Wax ?
Thanks
Bob Farber

[TelePlay]

Howard's Feed N Wax which I use on wood usually after Howard's Restore A Finish cannot be substituted for Renaissance  Wax ?

Anything can be substituted for anything at anytime. Any store shelf is loaded with options of the same basic product.

Howard's Feed N Wax msds states it is composed mostly of  mineral oil, diluted with naptha (light hydrocarbon solvent) and 4 additives: Carnauba wax, bees wax, paraffin wax and orange oil

Distillates (petroleum), hydrotreated heavy paraffinic mineral oil == 50-75%
Distillates (petroleum), hydrotreated light solvent ==  25 - 50%
Paraffin wax ==  1.0 - 10%
Orange oil == 1.0 - 10%
Beeswax == 1.0 - 10%
Carnauba wax == 1.0 - 10%

Mineral oil never dries, it is a petroleum product that will stay in a "tacky" liquid state forever. The light solvent, say mineral spirits, dilute and mix the ingredients and evaporates during application leaving the rest of the ingredients in place. Bees wax is a soft, organic wax and is pH neutral, 7 (great for sealing paper, etc). Paraffin is a long chain petroleum hard wax which is pH neutral. Carnauba was is a soft, organic wax and is a combination of several ingredients including acid esters (80-85%) and acids (3-6%). When mixed, the pH of Carnauba is made neutral but after several months on the surface of an object, it will turn acidic and affect whatever is under the wax. Carnauba wax on metal may not be the best. It may also affect some finishes. The combination of mineral oil, Carnauba wax and orange oil by actually soften some finishes as well. Orange oil may be added as a cleaner, fragrance and colorizer for the mixture.

The difference here is wood vs metal and when testing those dozen waxes for my polished bare metal 302, I stayed away from any organic wax that was acidic in nature. I was also looking for a wax (not a polish and/or cleaner) that would protect the surface and not itself affect the surface over years. I have a dozen different waxes in my dungeon right now plus several bags of wax flakes as I attempted to mix my own wax, with some success, until I discovered Ren-Wax and gave up on that. Most of the waxes I bought included cleaners, solvents and grit, which did not work out well on highly polished bare metal (dulled the shine due to abrasion and/or too thick of a wax coating left behind)

I use Howard's Restore A Finish on wood, a great product, but top coat it with Min-Wax Finishing Wax which is about 20% paraffin wax softened with 80% light aliphatic hydrocarbon, the wax solvent which evaporates in a few minutes leaving the paraffin wax. That provides a hard, non-acidic layer of protection on the refinished or restored wood. Could probably use MinWax on metal as well but the dry and buffing time ads to a process which is not needed when using Ren-Wax.

Putting an organic wax that is or will be acidic on metal is something I would not do. It might be fine for porcelain but then due to the high mineral oil content, it never dries to a hard, protective surface.

This or that was my adventure into finding the best wax possible for my polished 302 housing and turned out that Ren-Wax was best for that and everything else (except plastic housings) that I have worked with since.

Bottom line is you can use whatever you feel works best. My research led me to Ren-Wax and will continue to use it on everything from Bakelite to bare metal, MinWax on wood and nothing on polished plastic.

Hope this help those who may be interested. Feel free to refute anything I've stated if you can cite the opposing facts.


Found the following online about finishing wood:

" . . .  Howard's Feed N Wax is designed basically for easy use by housewives on furniture that does not suffer a lot of abuse and for that it is easy to apply, wipes off quick, and has a fair to decent combination of waxes in it which will last around 2 months or maybe longer if not in direct sunlight. Leaves a shiny somewhat oily finish, because of the Mineral Oil. Used on table tops, armoires, poly coated chairs and end tables etc. Stuff like that. "Housewife" stuff, wipe it on, wipe it off and go on to something else. The cleaners are the Mineral Spirits and Turpentine in the formulation."

     and

"The best wax for any topcoat is a natural ingredient paste wax without any petroleum based or petroleum assisted additives including stuff to make the product a gel. HFW and other "Citrus Additive" waxes also have petroleum additives.

Paste waxes go on as easy as the gelled waxes but they do need to be buffed. How much and how hard it is to buff depends on the product.

The best of these is Renaissance Wax which is made with 100% natural waxes but refined in such a manner as to make the product micro crystallized which simply means a smaller particle size. Smaller is good. Goes on as easy as Howard's. Has a finish that approaches some topcoats in hardness. Invented for museums. Looks expensive but per application is not cause you only need a teensy bit per coat."

Interesting and I was a bit surprised when I round that Ren-Wax reference, didn't go looking for it in me research on Howard's FNW.

[Sargeguy]

I never use wax on wooden phones, just shellac polished with 0000 steel wool. 

I am going to experiment with some Ren-Wax on a sign.  I have a few that look great when wet but look cruddy once they dry out, due to hazing caused by mineral/organic deposits. These deposits form in between minute cracks in the porcelain when the sign is immersed in water or mud and I have yet to find a method for removing them.  They make a sign look dirty. 

[TelePlay]

I never use wax on wooden phones, just shellac polished with 0000 steel wool. 

Yes, the other finish is shellac. I've actually mastered french polishing on stripped wood and it looks great. Lot of time and patience required but it turns out very nice.

Shellac is susceptible to any alcohol so table top use is not recommended.

I don't know what finish may be on a wood item so if I use Restore A Finish to "fill in" the defects, I end with MinWax. If I knew it was shellac, I suppose one could test using a cotton swab and some alcohol, I'd do what you do, shellac and 0000 wool.

Everything I do is hand applied, rubbed on except for metal paint. You have a deeper knowledge of old phones and their original finishes. The only wood I worked on is extension ringers and subset boxes. What you do makes sense.

[rfkimba]

Hi John,
Have you successfully used Re-Wax  on silver or copper?
Thanks,
Bob Farber
ATCA, TCI

[TelePlay]

Hi John,
Have you successfully used Re-Wax  on silver or copper?
Thanks,
Bob Farber
ATCA, TAXI

Yes, and that's what it was created for, to protect the metal surfaces of expensive art pieces on display in major UK museums, now used worldwide.

Here's the promo from the people who developed the wax.

"Renaissance Wax / Micro-Crystalline Polish

#1 choice of museums, galleries and professionals worldwide.

Created at the British Museum specifically for the restoration and protection of fine Art

The semi-synthetic micro-crystalline formula is entirely free of damaging acids. It is chemically neutral, and completely safe for even vulnerable surfaces

Guards against the damaging effects of humidity and other environmental conditions

Provides a barrier against fingerprints, water, alcohol and other spills. Forms a durable, lustrous coating that helps prevent tarnish and corrosion

Safe For Use On (Wood - Raw & Finished), Leather, Parchment, Paper, All Metals, Stones, Gems, Glass, Porcelain, Patinas, Enamel, Lacquer, Varnish & other finishes

Use on Furniture, Antiques, Sculpture, Pottery, Knives, Swords, Jewelry, Clocks, Paintings, Photographic Prints, Golf Clubs, Guns, Fine Musical Instruments, Fountain Pens, and More

A Little Goes a Long Way

Has a Shelf Life of Many Years When Kept Tightly Capped."

Only thing not mentioned is plastic and due to the solvent used to make the wax a soft cream, it may be the case that the solvent may melt or dull ABS and likely tenite. It would be an easy test, to try some on the inside of a housing, but since I never top coat plastic with anything, I never tried that test.

[Sargeguy]

I use it on copper and silver coins all the time.