Blacking

This topic has 46 replies, 23 voices, and was last updated 6 January 2012 at 20:34 by Sub Mandrel.

Viewing 25 posts - 1 through 25 (of 47 total)

1 2 →

Author

Posts
1 January 2012 at 16:16 #5830
Wolfie
Participant
@wolfie
Advert

1 January 2012 at 16:16 #80983
Wolfie
Participant
@wolfie
I understand that I can make things black by a chemical process.

Can I do this in my workshop, and are the chemicals easy to find, I don’t even know what they are called?

Edited By Wolfie on 01/01/2012 16:17:16
1 January 2012 at 16:26 #80984
Springbok
Participant
@springbok
Wolfie,

Bought some of this stuff at I think the Ally Pally some years ago and think they are still in business think I still have there flyer in workshop filing cabinet will go hunting and hopefully post it to you.

Bob
1 January 2012 at 16:32 #80985
Martin Cottrell
Participant
@martincottrell21329
Hello Wolfie,

I believe there are several suppliers who regularly advertise in ME & MEW who can supply “Chemical Blackening” kits. These can be used in your home workshop as far as I know without any specialist equipment, I think you just need some plastic tubs to pour the solutions in and leave the parts in to soak for a period of time. Try the likes of GLR distributors or Chronos, I’m sure I’ve seen them advertising the stuff.

Regards, Martin.
1 January 2012 at 16:33 #80986
Mike
Participant
@mike89748
Most gun shops sell barrel blacking compounds which work well on most steels. From experience, good for small items, but can turn out a bit blotchy over large areas. Complete de-greasing is necessary before use, then follow the instructions on the packet for “killing” the compound when it has done its job, otherwise rust results. Hope this is helpful.
1 January 2012 at 16:34 #80987
JasonB
Moderator
@jasonb
GLR do several kits and I think Bruce Engineering also have some

J
1 January 2012 at 17:13 #80992
David Littlewood
Participant
@davidlittlewood51847
Wolfie,

I have used Birchwood Casey gun blue with success. Despite the name, it actually gives a black colour, which can be made to have a blue hue only if the metal is highly polished and oiled afterwards. There are solutions for most common metals, though each solution often works on other metals as well, you have to experiment a bit. Many suppliers, for example here

C&L Finescale also sell a variety of solutions which I have used with success, see here

David

Edited By David Littlewood on 01/01/2012 17:15:28
1 January 2012 at 17:22 #80993
Phil P
Participant
@philp
Wolfie

I have used this stuff with good results recently.

http://www.black-it.co.uk/

Phil
1 January 2012 at 17:24 #80994
Kevin Bennett
Participant
@kevinbennett25223
have a look at this one http://www.black-it.co.uk/

kevin
1 January 2012 at 17:30 #80995
Wolfie
Participant
@wolfie
OK chaps I get the drift. There was me thinking I’d have to search for polychloridethingummyacetylenechocolateorangeethyl acid or something

Cheers as usual
1 January 2012 at 17:44 #80999
Richard Parsons
Participant
@richardparsons61721
Wolfi What are you blacking? Here is a dead cheap recipe which works on steel BUT as you will see from the method it is a bit crude.
Get some Dirty motor oil –yes dirty!. Heat the thing to be blacked to a dull cherry red and plunge it into the dirty oil! When all the fuss has dies down and the thing is cool enough to wipe then wipe it. It is best to do the job outside and down wind .
It Works
Rdgs
Dick
1 January 2012 at 18:09 #81001
Jon
Participant
@jon
The burnt oil will work on steels as many other applications will do also.

It all depends upon the quality required and finish.

Hot blacking is the best but operate in region 150 to 160 degrees. Cold blacking as Birchwood Casey and other gunblue kits waste of time except for screws.

There are cold/warm blacking formulas that rust the metal after painting on and have to be wire wooled off between around 7 coats, as used on English shotties.

Theres phosphating also quite rough to the touch.

Other metals will require a separate different process namely aluminiums and titanium requiring anodising, stainless forget it too costly.
1 January 2012 at 20:51 #81011
Wolfie
Participant
@wolfie
As a biker I can always lay my hands on some dirty motor oil. Just follow my mate’s Triumph
1 January 2012 at 22:49 #81021
Richard Parsons
Participant
@richardparsons61721
Wolfie as it is free get a bit of scrap and see. I think it may well work on rusty stuff but i have never tried

Rdgs Dick
1 January 2012 at 23:06 #81025
chris stephens
Participant
@chrisstephens63393
Hi Wolfie,

Everybody has concentrated on blacking ferrous metals, but you can “black” other metals with the various Carr’s Metal Black products.

chriStephens
1 January 2012 at 23:32 #81027
Terryd
Participant
@terryd72465
Hi Wolfie,

Clean new motor oil will work just as well as the ‘old’ stuff without the nasty toxins. I have done some very good blacking by that method. The ‘old engine oil’ needed is just an old wives tale (or should that be an ‘old engineers’ tale) We used to use new whale oil in the 1960s, but that’s quite rightly frowned upon now.

Here’s one I did earlier (before tempering):

You just don’t get much blacker! It only works on steel though

T

Edited By Terryd on 01/01/2012 23:38:53
2 January 2012 at 07:27 #81033
Richard Parsons
Participant
@richardparsons61721
Terryd Yes I know this but new clean oil costs money. Somewhere in my ancestors was one who came ‘frae Aberdeen’ since her name was Cohen one must draw your own conclusions. But they do not become more ‘careful’ than that. So as Wolfie says you just need to follow a 2 wheeled oil slick and you can get dirty oil for free. Seriously I think that there are various ‘chemicals’ in the dirty stuff that improve the blackening. That is why I always do it out of doors and to leeward of the house. These ‘chemicals are why I think the old ‘uns used whale oil. When using this technique the finer the finish on the item the finer the final coat will be.
BTW Woolfie has your friend never heard of a Kellogs Cornflakes (usual disclaimer). The packets (which are the best part of the whole thing) make almost bullet proof joint washers.

Rdgs

Dick
2 January 2012 at 08:24 #81034
Jim Greethead
Participant
@jimgreethead
This is the stuff I use: http://www.blackfast.com/

A friend in Queensland is still using some that he purchased so long ago that the distributor has moved twice since he bought it.

It comes complete. The concentrate, the small pails with lids to keep the diluted chemicals and labels on each of the pails. Full instructions included.

I keep mine in a plastic tub and just drag it out and use it when needed and then toss it back in the tub and put it on the shelf.

Jim
2 January 2012 at 09:19 #81041
Douglas Johnston
Participant
@douglasjohnston98463
I have used rapeseed oil from the supermarket instead of motor oil for a number of years and get very satisfactory results. As mentioned just heat to dull red and plonk into a container of the oil and the steel comes out a deep black colour.

Doug.
2 January 2012 at 09:24 #81042
Mike
Participant
@mike89748
Interesting that people have had success with new motor oil, because it has never worked very well for me. However, Terryd’s picture proves that I must have been doing it wrong. I have had great success blacking small items like screw and bolt heads by dunking them in melted margarine – the cheapest supermarket own-brand stuff. Makes the workshop smell like a chip shop on fire!
2 January 2012 at 10:14 #81047
Gordon W
Participant
@gordonw
Old diesel oil is best for blacking, older the better, and better still out of a proper old engine, eg landy or fergy. I assume it’s all the carbon black.
2 January 2012 at 12:26 #81055
Terryd
Participant
@terryd72465
Posted by Douglas Johnston on 02/01/2012 09:19:18:

I have used rapeseed oil from the supermarket instead of motor oil for a number of years and get very satisfactory results. As mentioned just heat to dull red and plonk into a container of the oil and the steel comes out a deep black colour.

Doug.

Hi Doug,

I haven’t tried veggie oil myself but I have heard that it gives good results. The advantage of oil blacking is that one gets a nice lustrous finish and some protection against rust. One of the problems though is the relatively high temperature needed to achieve a good finish. I think that is the most important thing. When hardening tools etc it’s not so bad but for vulnerable parts which may warp it could be a problem.

Hi Gordon,

I’ve tried all sorts of oil over the years and was always told to use dirty motor oil, which I did until I had none available and needed to quench some tools I was making. I was very surprised to find that I obtained better results with new oil. Also don’t forget that mineral oils are all hydrocarbons so already contain large amounts of carbon in the chemical structure which would be released at high temperature I would think. Perhaps that could be confirmed or otherwise by those members of the forum with a better knowledge of the chemistry involved.

Best wishes for a happy New Year,

Terry
2 January 2012 at 12:42 #81056
David Colwill
Participant
@davidcolwill19261
If you’re near Nottingham I have all the cold black chemicals for steel, which does not involve heating.

Dave.
2 January 2012 at 19:59 #81086
Sub Mandrel
Participant
@submandrel
I have used jenolite koldblack for small components, it even blacks brass-just. I used it to disguise the brass chain on my crane.

You get a more even result by quenching in oil, and you don’t even need to use motor oil – I use a golden syrup tin half full of rapeseed oil for medium sized components and it gives a good, durable finish.

The clamp in this picture (taken yesterday) was blacked in rapeseed oil years ago.

The pale colour is an artefact caused by me photographing a black object on a black granite block.

Neil
2 January 2012 at 21:30 #81105
Jim Greethead
Participant
@jimgreethead
I prefer to avoid heating the object but if anybody wants some suitably dirty oil from a Fergie, I am prepared to swap a sump full for some clean stuff.

Jim
Author

Posts