Sciencemadness Discussion Board

HgCl2

knight guitars - 14-5-2011 at 07:16

Hi more stuff about bluing, got given a very old book which includes a lot of formulars for slow rust bluing od steel but a lot of them include HgCl2. I cant buy this stuff in the uk and was wondering if there is anything I can substitue it for?

A typical formular is :-

Hgcl2 15g
HNO3 150ml
FeCl3 90ml
CuSO4 7g
Distilled water 960ml

Jor - 14-5-2011 at 08:21

You can make the HgCl2 yourself though, from elemental mercury. However this is dangerous.
I do not know an alternative but I highly recommend you to not play around with Hg salts in such quantities as they are highly poisonous.

knight guitars - 14-5-2011 at 08:37

Thats why I'm looking for an alternative if possable I have about 30 forumlars and neigh on all of them have it in them, I'm trying to figure out what purpose the substance plays in the solution. I have a full hazmat suit and fully extracted workshop so the exposure risk is lessened but I dont want to have to start dealing with highly toxic substances if I dont need to.

mr.crow - 14-5-2011 at 08:43

15g? Yikes!!!

Since you already use nitric acid you can just add some Hg metal to make HgNO3 in situ. The chloride ions will be oxidized away by the nitric anyways.

knight guitars - 14-5-2011 at 09:50

Thanks Crow just need to get some elemental mercury now then, or go about stealing people's thermometers

The WiZard is In - 14-5-2011 at 10:40

Quote: Originally posted by knight guitars  
Hi more stuff about bluing, got given a very old book

A very old book is not very helpful.

-----------
RH Angier
Firearm Blueing & Browning
The Stackpole Company 1936

p. 49
Mercuric chloride
...is a well known, anhydrous, strongly rust-producing
body, of frequent occurrence in browning solutions.

Mercuric sulphate
... exceptionally used, less soluble and oxidizing than
chloride, appears of doubtful value for solutions.

I would posit — if you replace the Hg chloride you will have
to create a completely different formula. Just use a published
formula that doesn't use Hg chloride. [File under either KISS or
Occam's depilatory device. ] Potassium nitrate at 315o C would
seem the easiest way to blue.

Fruit Acid Black perhaps?



djh
----
I am interested in getting a copy
of the current edition of Ullmann's
Encyclopedia of Industrial Chemistry,
however, I cannot afford its US $12 000
price. Being long on spare time and short
on exchequer, I have decided to go to
the library and hand copy its 28-volumes.

To make the economics work - I am planning
on copying it on the back of old cereal box's,
and making my own ballpoint pen ink. To
make the ink I need a 55-gallon drum of
thiodiglycol (solvent). Can anyone supply it
it Europe? [My agents will transship it to my
summer home in Yemen.]

Thanks in advance.


woelen - 14-5-2011 at 10:56

If you replace HgCl2 by Hg, then replace the CuSO4 by CuCl2. The chloride is essential in this formulation.

knight guitars - 14-5-2011 at 12:49

Take it your talking about hot nitre bluing there Wizard its good for decorative parts but its not hardwearing enough for whole barrels, shame as the color is superb. Never heard of fruit acid black.

And thanks Woelen.

The WiZard is In - 14-5-2011 at 13:52

Quote: Originally posted by knight guitars  
Take it your talking about hot nitre bluing there Wizard its good for decorative parts but its not hardwearing enough for whole barrels, shame as the color is superb. Never heard of fruit acid black.

And thanks Woelen.

Well - da cited book sez. (p. 123) — Springfield Armoury used it,
albeit with 8-10% manganese peroxide. The following paragraph
sez — According to Martmann, a temp of 315o C, that is, about
the melting point of saltpetere, is necessary for producing a deep
blue colour: the same author (and many others) state that the
addition of manganese peroxide is of no special advantage, save a
slight quickening of the process.

F Hatman, Färben der Metalle. Wein, 1912.

Have you tried the Newsgroup rec.guns?

NB - If'n you bring Angier's book up @ Google.com/books you can
search and read. Try Fruit acid black for practice.

I removed this en bloc from Google.com/books

The information in our possession at present as to Colonel Bufflngton's process, from the Army and Nary Journal, is derived from a correspondent who has been for many years a manufacturer of machine plant and special tools for gun-making and an expert in the selection and treatment of metals. We learn that the experiments, which have proceeded by slow degrees from the plane of investigation to that of practical application, have been of long continuance, and that the testing has been of a character exceptionally severe and thorough. In pursuing his experiments Colonel Bufllngton has always kept in view the practical rather than the theoretical, and the result of his work is the formulated system of an industrial expert rather than the more ambitious but less avuilablc scheme of a consulting engineer. Every one skilled in the art of ash or baked bluing processes and the time and care required for the acid process of barrel browning," says the correspondfnt, "will be pleased to learn that by immersing and keeping the parts in such a condition for six minutes, in a bath of saltpeter, 10 parts, and of black oxide of manganese. 1 part, heated to about 600 degrees Far., a beautiful blue black color will be secured which will wear equal to, if not better than, the best acid process." The operation requires no skilled labor, a cast-iron pot deep enough to cover the parts to be treated, arranged in such manner that a uniform heat can he maintained, being the only apparatus needed. At the National Armory, they are using this process for all the gunparts formerly blued—such as butt-plates, triggerguards, bands, tips, etc. They are also treating the bayonets, and are about to try the process with the barrels. Especially notable is the fact that this process will not prejudicially affect the spring temper, and will draw case-hardened parts, requiring toughness, to the proper spring temper. The economical advantage is thus differentiated between the old process and the new—the old barrel browning by acid requires at least four and better six days time, while the new process consumes six minutes—the former demanding an expert and the latter a laborer. The Barfflng process, as is well known, takes from ten to fourteen hours, with the constant liability of doing a positive or permanent damage to pieces thuB treated.

It will be seen from the foregoing that, though Colonel Buffington's process is applicable both for browning and anti-corrosive purposes, it has not yet been applied to the parts of the action, other than the springs. The very economical results of the new process are thus far most pronounced, the saving of time and labor being considerable. We now look for a trial of the anti-rust virtues or the process upon the bolt-action and limb-work of the several repeating rifles. Should Colonel Buffington have merely succeeded in substituting a new formula for the old uncertain bluing and browning processes, he will have scored a success; if he has at last hit upon a real anti-rust treatment he has gained a victory.

I suspect that if you get involved in searching Google.com/books
for blueing/browning — we will never hear from you again! I would
suggest using their Advanced search - starting with Full view
only.

knight guitars - 14-5-2011 at 14:22

Wizard by name Wizard by nature I stand corrected. Thats fantastic as the salt bluing does give of a lot of fumes which make me less than popular with the neighbours. Just thinking how to heat a steel tank to 600f been using propane for the tanks of .0225m3 and getting them to 290f, might be worth going over to electrical elements

The WiZard is In - 14-5-2011 at 17:03

Quote: Originally posted by knight guitars  
Wizard by name Wizard by nature I stand corrected. Thats fantastic as the salt bluing does give of a lot of fumes which make me less than popular with the neighbours. Just thinking how to heat a steel tank to 600f been using propane for the tanks of .0225m3 and getting them to 290f, might be worth going over to electrical elements


I would worry 'bout... taking the temper out of the barrel!

A lot of the original Springfield's had poorly tempered
receivers ..... resulting in a bunch of injuries. For details
bring up one of my favorite books at Google.com/books
Hatchers Notebook and search internally for Springfield
receivers.

I would note in passing a book I shelve...

Hughes and Rowe
The Colouring, Bronzing and Patination of Metals
Watson-Guptill Publications 1991

It do be for the artisan, however, you may find it interesting.
The cover price on my copy in US $80



knight guitars - 15-5-2011 at 01:31

I wouldent use nitre bluing for firearms sounds just the job for air rifles though, they only work at relatively low pressures when compared with firarms. Also heating to 315c your not into the annealing range on most carbon steels so should still be safe for those types of parts. Will have a go with some small parts like trigger guards and scale it up.