chemical blackened steel

[arkade31%]

Hello everyone,

Does anyone have any info on blackening steel, that does not involve heat,oil
or expensive chemicals. I am looking at blackening some tools as cheap as possible from readily available chemicals if at all possible. Monetary funds seem to be in short supply at the moment, and will continue to be so in the near future.

cheers.
Arkade31%

[scooter]

Gday Arkade, thread here (http://www.woodworkforums.ubeaut.com.au/showthread.php?t=47558)but doesn't meet your criteria.

Black spray paint mebbe? :D


Cheers................Sean

[Wood Butcher]

Have you looked at using Gun Blue? It won't make the steel black but will make it a nice blueish/black. Do a quiok Google search on gun blue and you will find some good info on the process.

[neksmerj]

I have restored a number of old tools, and even with new ones I've made, I like to give them a couple of coats of gun blue. I use Birchwood Casey Perma Blue. You buy it in a kit, or just the Perma Blue on it's own. The full kit is a waste of money at $30, just buy the blue at $20 for 90ml.

The full kit contains things like sand paper, steel wool, and metal prep etc, stuff you will already have under the kitchen sink.

If the part is rusty, place it in a plastic container and cover with it with white vinegar.

Next morning, walla, the results are surprising. If a few parts are still rusty, give them a going over with a wire brush, then chuck it back into the vinegar.

The part needs to be clean, and I find normal dish washing liquid and a scrubbing brush, do the trick.

Pour some of the bluing liquid into the lid, and apply with a small brush. It goes on streaky, until a full cover is applied. Rinse with detergent to stop the process.

Perma Blue is not permanent, and will rub off in time. Finish the part with some sewing machine oil, and Bob's your uncle.

To obtain a long lasting blue/black finish, the only real way is to take it to a plating shop that specialises in black oxide plating. The oxide coating is permanent, and will not change the dimensions of the part, well 10 microns maybe.

My two bob's worth,

Ken

[BobL]

Phosporic acid and a little detergent to help it stick will make it go blue-black. It works better if you actually let the steel rust just a little first.

[son_of_bluegras]

Do you want black or the darkened blue/grey (or blue/black) of old carbon steel? And how permanate?

The dardened surface can be gotten through any number of kitchen supplies. Vinager, lemon juice, mustard, tomato juice (or anything containing tomato juice), potato juice, many fruit juices: all of these will force the patina that forms over time but initally it will be rather thin and may wear off with just a little abrading.

ron

[Grahame Collins]

To obtain a long lasting blue/black finish, the only real way is to take it to a plating shop that specialises in black oxide plating. The oxide coating is permanent, and will not change the dimensions of the part, well 10 microns maybe.


Au contaire
my friend neksmerj.
There is a possibly better alternative (if boiling water is not too much heat to bear.-I know the question did say "did not involve use of heat".-The cook may never know if you get in quick while she"s at the hairdressers-but use your own S/steel boiler-it goes black inside.

There is a finish which is called Parkerising which has been discussed here on the forum ,can be performed at home .

If careful preparation is undertaken it not hard to do at home.

If one is familiar with the army 303's the black oxide coating on the receiver and breaches is a parkerising coating.

I have Parkerised engineers block squares at school.This was performed by boiling in a stainless steel boiler.

Pure demineralised water, phosphoric acid (rust killer preparations have these) powdered (out of a flat D cell battery maganese dioxide, a handful of plain unsoaped steel wool, wet and dry paper is all you need.

Clean up up the tool (the smoother and shinier the finish,the better) clean it up with degreaser and metho,

Boil up half the boiler of water, and a cup of phosphoric acid add the handful of steel wool and half a cup of Maganese dioxide. Hang the tool on a wire( aluminium coat hanger) and leave it in for twenty mins.

Remove rinse in hot water,let dry and while hot coated in a thick oil or wax( U beaut wax will work well)
For mulitple tools just keep the boil going.
Once cooled down it looses its usefulness.
Dispose of waste carefully.

People like me with rusty salty fingers leave no impression on parkerising. On a rifle blue finish I can rust that overnight.

I hope this helps to add to our knowledge pool.

Grahame

[neksmerj]

Au contaire, my friend Grahame. (What does au contaire mean?, sounds good)

I must give your receipe a go.

Before I do, will the parkerised finish rub off, and does it also offer some degree of rust protection. I'm assuming a factory applied finish will last, is this also the case with a home applied finish?

Always enjoy reading your informative responses, including mispalled wurds.

When's the next BBQ?

Ken

[DJ’s Timber]

Au contaire, my friend Grahame. (What does au contaire mean?, sounds good)



Is French for "On the Contrary"

It's also spelt Au contraire, not being picky on your spelling just giving you the correct pronunciation

[Grahame Collins]

Main Entry: au con·traire
Pronunciation: O-kOn-trer
Function: foreign term
Etymology: French
: on the contrary


R Ken,
Sorry I forgot an R .Yes! I am the typo king, I can spell some times but my fingers ( both of them)have yet to learn.

Our block squares came as shiny oiled bits of metal and were rusty in weeks.

Oxiding the squares as per the recipe has had them rust free for 12 months or so.A heavier stickier oil works far better than the WD 40's or RP7's

The manganese dioxide power powder comes from a crushed up dry cell or if you have access to a pottery place it is sold there in bulk.A dust mask is a good idea as manganese is said to be carcinogenic.

The formula came from a military rifle restoration web sites.

Phosphoric acid is found in the form of the anti rust solutions often found in the auto accessory shops and paint shops.
A 20 minute simmer(rather than a boil) is a better description of what is required.

A bit of prep is required,but ultimately is payed back in the longevity of the coating.

regards
Grahame

[glock40sw]

Grahame.

I'm looking for a hard wearing finish for Aluminium.
I've been think of Anodising.
Are there any other finishes that could be used?
Will parkerising work on Ali?

[echnidna]

black paving paint over a light etch primer

[soundman]

wattyl super etch black followed by black thinners based paint of choice like GMG flat, black QD enamel or black acrillic.

let dry then bake at 120C for 2 hours starting from a cold oven.

cheers

[Grahame Collins]

Will parkerising work on Ali?

Sorry Mate !
I have not heard about anyone using it on aluminium.

Cheers
Grahame

[soundman]

I don't believe parkerising will work with aluminium because I understand it is a chemical reaction with the steel.

there are some kitchen chemistry things you can do with aluminium.... but most of them involve boiling caustic soda or something similar.

I'll have a look in the old books I have.

cheers

[Woodlee]

Grahame.

I'm looking for a hard wearing finish for Aluminium.
I've been think of Anodising.
Are there any other finishes that could be used?
Will parkerising work on Ali?


Heres a link to a site where the guy has a home set up . since I bookmarked this page a few years ago he has started selling kits and gone a bit commercial ,but all the info is there to set up your own anodising plant on a small scale.

http://www.focuser.com/atm/anodize/anodize99.html

Cheers
Kev

[Master Splinter]

RIT or Dylon dyes will give you a satisfactory finish for anodised aluminium; if you are after a really solid black you may have to leave it in the dye for 2-3 times as long as expected.

If you are anodising some of the weirder alloys you may find it is impossible to get the colour you want.

Here's (http://astro.neutral.org/anodise.shtml) another good site about it.