Patinas and Finishes

[Woody]

We spend countless hours at the forge creating beautiful objects and then devote mere minutes to applying a finish to the object. Often all it gets is a quick blast from a can of flat black spray paint or we burn some wax or oil on the metal and call it good. I think the fruits of our labors deserve better treatment. How about everybody listing their favorite ways of finishing their metal creations. Some of my favorites are listed below:

1. Watco Dark Walnut Oil with a little gold paint mixed in to give an antique bronze finish.

2. Dilute oil based paint with at least 50% polyurathane varnish to give a translucent paint finish where the metal will show through.

3. Cold gun blue with a lacquer or clear coat finish applied over it.

Woody

[the_sandy_creek_forge]

Favorite finishes for a project:
1). Brass brush hot with a coat of clear coat / varnish / beeswax
2). Straight beeswax, applied hot and then polished with a CLEAN buffing wheel

There is an effect that i have seen and really like (but have not tried), it's a kind of chemical copper coat that is left to oxidize and then sealed, so you get the dark steel color and the light blue oxidized copper color.

I am also growing somewhat fond of the Gilder's (sp?) Paste finishes with a clear powder coat, and might end up trying them out soon.

[StephanFowler]

I tried out just straight "Minwax" wax paste polish, applied hot, several coats until a good dark patina is achieved, I'll let you know how it wears, but seems to do well so far

[Marc]

I color in different ways depending on the look I want.
- Brass brush on black heat
- Wire brush on my angle grinder to get it shiny
- Manual wire brush to leave it "natural"
- Scotch-brite pad to buff out high spots to get definition
- A light coating, more like an over-spray,of some colored Rustoleum, for color
- Temper colors
- Good, old, flat, matte, or satin finish black paint
- Whatever strikes my fancy.

Then, on top of that, I tend to use Rustoleum clear matte. For indoor pieces, that does a nice job of keeping the underlying color while giving it a decent coating. That stuff dries very quickly, which is a nice benefit in a multi-use shop with no space for a paint booth.

I've also used Penetrol for a glossier finish. That takes longer to dry, but it seems to give a clearer finish.

For outside stuff, I've really only done some shop door strap hinges and went with a primer of cold zinc galvanizing and satin black Rustoleum on top of that. It's only been two years up here in NH, but not signs of any rust at all so far.

[JerryCarroll]

I've been using Future brand acrylic floor finish for several years on inside stuff after preping (scaling--degreasing) with excellent results. Outside I use an automotive brand of acid etching primer with what ever color is wanted/needed.

[V]

I

[frogvalley]

In order of preference/amount of usage.
1.Clear Gloss Rustoleum-my favorite, shows all the details and works great in or out for years. Great silver black finish over mostly descaled work. Very artsy if you ask me. Reasonably chip resistant, quick drying, polyurethane is better against chipping but takes forever to dry. Most used for my sculptural work, in or out of doors. By far the most used finish here, ten to one over the others.
2. Boiled linseed oil, cold application, air dried- for triangles/dinner bells or hooks and whatnot..
3. boiled linseed oil, heat dried in forge or oven depending, or hot applied and heat dried. Hooks and stuff.
4. Vegetable oil, hot applied, or even baked on- several coats, best for the functional bowls that I make , you can eat out of it like seasoned cast iron pans and you can easily re-apply.
5.beeswax, hot applied, two coats,
6. beeswax and linseed oil mixed, hot applied, two coats, also reasonably edible for eating utensils
7. Gloss black, flat black, other colors of rustoleum over appropriate primer. Tend to hide detail. My least favorite as it is not that much more durable than the above finishes but is a multiple application with many coats. 2 primer, 3 finish for spraying, one and two for brush applied. I use- volume wise- almost as much as the clear, but thats because the jobs that tend to need this finish are custom gates and fencing, bigger single jobs rather than individual sculptures or art pieces.
8. Powder coating- NEVER. Don't even get started on that one.

[Ezra]

O.K.
Here's a newbie question about it.
On page 92 of "Wayne Goddard's $50 Dollar Knife Shop", there is a picture of two Damascus letter openers.
They have an almost glossy green finish. Beautiful in my opinion.
How did he do that? What about other colors? Red for example...
Sorry if this has been discussed at length before, but it's all new to me.
Ideas or opinions please.
Thanks!

[Woody]

Ezra, I have no idea since I have not seen the picture, may be some sort of guilders paste finish.

Woody

[Ron Hicks]

Some good ideas I need to try a few
I dont know If its right but been using Johnsons Patse Wax after clean up get a reall good black heat and wipe on the wax. Ill do this a few times, ends up looking kinda like a blued finish.

Now If you want that glopey clumps of goo look use the foam pad that come in the wax- dont ask why I know :D

[trying-it]

Copper Sulfate can be purchased in crystal form. Dissolve some crystals in water, emmerse or spray/mist item and a copper petina will result. Oven time the copper petina itself will turn to the aged copper "geen" finish. Apply paste wax after item has dried.

Another favorite is liquid cold gun blue; it will even blacken fresh brazing rod welds.

[Ulysses]

I just use two methods

One would be to shine the piece as bright as you can get it, paying no mind to the low spots, and then from a black heat hit it with a brass brush until tone is achieved.

The other method would be to use beeswax or in conjunction with the first method.

[Anvilfolk]

I saw a demonstration by a blacksmith from the UK once (unfortunately, I can't recall the name, sorry).

He had some sandblasted pieces of mild steel sheet, and what he did was put them in the middle of several types of wood shavings (in a tupperware box). He added some water by fine-sprinkling it, and after a couple of minutes, some sort of acid in the wood shavings had reacted with the metal, giving it really, really nice colours and patterns.

I can't remember the types of wood, but I'm guessing wood shavings aren't that hard to find/make - I'd try oak, but loads of others ought to do the job. You can also use different types of shaving to give different patterns. It was amazing! Maybe leaves work too?

Never done it myself, but I've seen it with my very own eyes! Just make sure the pieces are clean. Not polished, just clean!

[Ice Czar]

variegated rust patina







1.mist on a solution of hydrochloric acid and water allow to dry
(typical mix rate is 1:1 water to the already diluted Muriatic Acid sold for etching cement)
the more solution employed the larger the resultant ferrous chloride residue will be

2.sprinkle (spot)on a solution of technical grade (35%) hydrogen peroxide, water and hydrochloric acid allow to dry
(500ml hydrogen peroxide, 200ml muriatic acid, poured into a 5 gallon container then topped up with water)

3. with a hose handy, flood the steel with a heavy mist of the peroxide mixture you can try various dwell times or mist first with water for a more diluted effect.

4. rinse well allow to dry

step one produces a pickled steel free of rust with deposits of ferrous chloride (iron chloride II) which are loosely attached to the surface, when rinsed of they will rust at a natural rate for oxidation with water

step two produces deep brown spots as with all the rusting, temperature effects the speed and how dark they appear, oxidation occurs from the peroxide

step three is a more general oxidation state from the peroxide

step four washes the ferrous chloride away and is a passivation phase


5. employing the original hydrochloric solution spotspray the darker areas to burn in lighter specks (i often do this with a light film of water already on the sheet for a more subtle effect)

5A. (optional) repeat steps 2 thru 5 building depth till you ruin it, get sleepy, poison yourself or just give up

6. six passivate the piece throughly with either a pressure washer or as powerful a steam from the hose as you can manage, be careful with a pressure washer as it can create uneven removal (another potential variable you might use to effect)

7. accept the fact that whatever you see while your doing this isnt going to be the end result when you are done, and further that variables beyond you control will impact the end result. Dont expect to be able to easily replicate a finish from one day to the next. temperature, humidity and airflow all effect what you get.

Depending on what I now see I use a propane weedburner for heating, a swamp cooler for higher humidity drying, a compressed air nozzle, different dilution levels, mix levels and dwell times. (have even used straight peroxide)

8. we generally seal with an acrylic (any acid missed in passivation really shows up)

disclaimer
hydrochloric acid will stunt your growth, put hair on you palms and make you sound like a girl (if yoy arent already) review the MSDS and employ all cautions, ferrous chloride will make you a slobbering idiot (if you arent already) its disposal is regulated by the EPA (who will make you a slobbering idiot) and is toxic, review the MSDS take proper precautions and dispose of correctly (note iron chloride II when upgraded with chlorine becomes iron chloride III which is used to etch copper plates, when I find a safe way to do that I'll post it )

[RichHallstrom]

I have been using used peanut oil from a resturant with good results.

[steveh]

jerry darnells mixture of beeswax,linseed oil and turpentine made into a soft paste has worked well for me