How do you rust blue small, multi-part subassemblies such as a 3 position safety? Do they have to be taken apart?

MKane160

Yes. If you don't, it will never card right. Also hard to keep it from rusting later if you don't get all the nooks and crannies oiled right.

I watched the rust bluing video, from AGI, where the guy did a sight as a single piece... I wouldn't have...

not to mention looks, if you don't stop ALL the rusting (remember, you are exposing them to a acid) the pins will rust in place to the body and the springs will weaken over time.. and the smooth camming of the safety now feels like sandpaper

jeffe

Thanks.....

MKane160

Here is a recipie and instructions I got from Tony Small from Australia:


Thanks for your reply, the recipe is as follows.
Hydrochloric Acid...........1.5oz
Nitric Acid.................2oz
Distilled Water.............1pt
Iron nails..................4oz
Mix acids then add to the water ( in a pyrex bowl, the reaction with the
nails gets hot ) then dissolve the nails till the reaction stops. You may
be able to get your Druggist to mix the acids for you, I had to buy more
than I needed and the Nitric acid lost it's potency after a year.
Even though the ingredients add up to more than a pint you loose quite a
bit with the reaction.
Be very careful with the acids before and during the reaction, wear rubber
gloves and face protection. After the reaction the mixture is pretty
harmless. I store mine in a dark bottle supplied by my Chemist.
Preperation.
Remove rust and dirt and polish the parts as best you can. I sometimes
give mine a light sandblast.
Put on rubber gloves and eye protection.
Clean the parts with cold caustic solution 10%. Rince with clean running
water ( from the hose).
Dry with a clean towel then lay the parts on the towel or clean cloth or
paper.
Using a Q tip apply the well shaken solution to the parts getting a thin
coat on, you will see the steel change colour as the blueing stuff dries.
The solution will settle out so you must shake it before use. I tried
using the clear stuff but the blue was very pale.
Hang the parts up using steel hooks, I put a long wire down the barrels
and hang them on that, you can leave the wire in till finished.
If you haven't cleaned the parts properly you will know it as the stuff
will not wet the surface.
Next day there should be a light coat of rust on the parts, this is good.
You will need something to boil the parts in. I use an old electric jug
for the small bits and a trough I bent up out of flat sheet metal over a
gas burner, for the barrels.
Boil the parts for about 5min and the rust should turn black, this also
neutralises the previous coat.
Put on cotton gloves and when the parts have cooled down a bit use a fine
rotary wire brush to take off the black coat.( the gloves are so you dont
put oil from your hands onto the parts).
The wire brush also polishes the surface, but dont use too much force,
just enough to remove the black coat.
Apply the next coat directly onto the parts, the colour should change
dramatically this time.
Hang parts and repeat the process the next day. After the third coat you
should have a very dark black blue shiny finish.
Apply a coat of WD40 and the job's done.

Cheers
Tony.
Location: Australia | Registered: 25 June 2005