Rust Bluing?

[Sneakfoot]

I'm about to attempt my first try at rust bluing. I have been reading up on it as much as I can find. Most instructions say, bring to a 320 finish. This seems like it may be a little rough. I was thinking that maybe this is necessary to start a good foundation? Would it be wrong to bring it down to a smoother finish?

[Walkingwolf]

I have rust blued over original finish without roughing the surface. It will take more cycles to get dark though. I would not personally go 320, 420 would be a good base to go from.

[andremajic]

You need a little "tooth" for the rust to take on. Anything higher than 350 grit is a waste of effort IMO.

You can go higher on the polish but the rust will bring it back down to about 350 finish.

Your polishing work and attention to detail will definitely show through in your final blue, so don't just rough it up and say "that's good enough".

Read my FAQs on my rust blue and follow the instructions on my thread, "Andy's rust blue WIP" to get a good picture tutorial. It's linked to my sig.

Andy

[LAGS]

On all my Rust Bluing Jobs, I either Bead blast the metal, or actually Sand Blast the metal for a more Mat Finish.
Highly polished metal does not work well with Rust Bluing.
The smooth Polished Steel, when you try to apply the acid is like trying to wipe clear water on Glass.
It does not go on evenly and streaks really bad.
Rust blue will never give you that High Polished Deep Blue like some other bluing.
But it protects better than any other form of bluing.
Parkerizing is not Bluing, it is actually acid Etching, and far more rust resistant.
I have Yet to have any of my rifles that I Rust Blued , rust in any way.
That goes for the handguns too.

[oldred]

Most instructions say, bring to a 320 finish. This seems like it may be a little rough.


On my first couple of jobs I thought the same thing and just couldn't make myself accept the fact, and it did turn out to be a fact, that going finer is not better! What really convinced me was when I did a barrel on an old Stevens shotgun and in an attempt to hide some minor pitting I stopped at 180 grit (wet sanded, 3M premium auto body paper) thinking to get a matt finish, was I ever surprised at the results! What I found was that there was almost no (if any!) difference in gloss to the 400 grit surface I had used before but it took fewer applications and the finish came out even darker, that darn thing looked great! I have since learned a lot more about the process and now it makes more sense, the rusting process not only erodes away peaks of the sanding marks but the oxidation layer fills in the tiny microscopic valleys leaving a smooth surface despite the coarser grit. What I would suggest is to test an application or two on a piece of scrap steel with both a fine and a coarse grit surface, I think you may be surprised and may even find yourself using a coarser grit than than the 320 instead of finer. On most of what I do now I stop at 240 (wet sanded) since it seems to be a good balance and produces an excellent surface sheen and color.

[Blackwater]

For a really good rust blue, I've been told by a very experienced 'smtih (one of PO Ackley's boys) that you CAN do a good high polish, but if you do, it takes longer to get the bluing to start to take, but once it does, it really makes for the ultimate in beautiful finishes. Since rust blue is a slow process to start with, few want to take the extra effort to get a mirror finish AND that wonderful and tough reust blue finish. Wish I could give a testimonial, but I'm one of those who likes the conventional results, so I just thought I'd pass on what I was taught.

[Kevinakaq]

320 finish for most rifles is just fine and gives very impressive results. Going up to 400 plus increases the blueing time/applications and increases the "presentation" quality of the firearm. I Personally use 320 95 percent of the time and I am a picky person. If i was bluing a custom rifle with a Parker And Hale barrel (project is on my bench, lol) I would go through the additional work of applying a finer finish.

[johnson1942]

lags is right, bead blasting or even sand blasting will give you a more longer lasting durable finish. the rustblue really gets down into the pores if you can call it that. after it is done and the blueing is done rub in a good quaility paste wax. make sure you boil good in water with a little bakeing soda in it when done as you want to stop the rusting action.

[BrentD]

Everybody has their druthers. I polish to at least 600 grit and usually 800 or better. Properly done, you don't need "tooth". And, if you like you can have a much nicer finer finish. Not a gloss, but a lot closer to semigloss.

If you rust blue and can see the direction of polishing then you are to coarse for me.

Like I said, everyone has their preferences, but you will never ruin anything by polishing more.

[Walkingwolf]

Everybody has their druthers. I polish to at least 600 grit and usually 800 or better. Properly done, you don't need "tooth". And, if you like you can have a much nicer finer finish. Not a gloss, but a lot closer to semigloss.

If you rust blue and can see the direction of polishing then you are to coarse for me.

Like I said, everyone has their preferences, but you will never ruin anything by polishing more.

My experience has been a finer polish rust blue takes well over 10 cycles, usually for me around 15. Metal exposed to the right conditions naturally oxidizes, it does not need tooth.

[gnoahhh]

I polish barrels (rifle and SxS shotgun) to 400x, and get fine results with all of the different solutions I have tried. On a whim, I polished a Savage 99 receiver to 800x and got a shinier result, but like Walkingwolf said, it took a whole lot more applications. In fact I almost gave up and started over, but I pressed on regardless and was rewarded for my perseverance.

[BrentD]

It takes as long as it takes. The point is to produce a desired finish, not to get it done fast. If you want fast, bead blast and hot dip.

I use a diluted rusting agent when I want the finest finish, I also time my boiling sessions in accordance with humidity and temperature. A fine finish cannot be forced fast, or you will get the pitting that produces the normal matte-like finish that is not generally desirable. More cycles, faster cycles and weaker solution are the three main steps in producing a fine finish.

[andremajic]

It takes as long as it takes. The point is to produce a desired finish, not to get it done fast. If you want fast, bead blast and hot dip.

I use a diluted rusting agent when I want the finest finish, I also time my boiling sessions in accordance with humidity and temperature. A fine finish cannot be forced fast, or you will get the pitting that produces the normal matte-like finish that is not generally desirable. More cycles, faster cycles and weaker solution are the three main steps in producing a fine finish.

I've gotten good results with very weak solution that I've diluted by half. I can tell you're saying this from experience.
A little goes a long ways...

[Sneakfoot]

Guys I just gotta tell ya! I been rubbing on this rifle now, daily for over a week. The thing is full of pits and some of the castings aren't flat. The barrel has some dents, which I mostly removed by filing. I started with 80 grit and worked my way to 400 , a couple of times. Just can't get all the tool marks out. Gonna have to settle.

[andremajic]

If this is your first attempt at rust bluing, try doing it on a cheap tool first to get a feel for the process before starting on the rifle. Sometimes it's good to step back from a project and go slow.

This would give you a little breathing room and confidence.

Andy

[Lead Fred]

We talking what predated bluing? That would be browning, polished rust.

Or you talkin some new fangled suds?

[Sneakfoot]

We talking what predated bluing? That would be browning, polished rust.

Or you talkin some new fangled suds?

This is a Stevens Favorite. Now that I 've said that, please purist, don't flood me with your, you should have saved the rifle speech. Believe me I did the rifle a favor. Pun intended. This thing was a rust bucket, rifling's shot. HA! I have already relined the barrel, and it shoots very well. Will make a nice squirrel gun. Thinking I'll bring the finish back to 320 and wipe away.

[oldred]

I know others have voiced differing opinions and if it works for them that's great but I have tried everything from a mirror polish to the 180 grit and I have to agree with your choice of the 320 or maybe even a bit coarser than that. In all honesty I can not see any trace of sanding marks with 240 grit and anything finer than 320 only seems to take longer and require more applications for the same results except for maybe a lighter shade. YMMV

[Geezer in NH]

Rust blue is labor intensive, no shortcuts it takes patients.

[sparky45]

I finally got around to using the Rust Blue solution and while the results are good, I should have continued the process. I took down my LCT to rebuild it with all new parts (a used press I acquired the first of the year) and decided to re-blue the steel columns and the steel handle. I didn't get any before pics, but there was some rust on most of the steel parts.
First pic is of the re-blued parts:
http://i1201.photobucket.com/albums/bb351/glynnm1945/LCTd_zpsxw2gi1ps.jpg (http://s1201.photobucket.com/user/glynnm1945/media/LCTd_zpsxw2gi1ps.jpg.html)

Second pic is of the LCT and the un-assembled parts :
http://i1201.photobucket.com/albums/bb351/glynnm1945/LCTc_zps5zpscs8v.jpg (http://s1201.photobucket.com/user/glynnm1945/media/LCTc_zps5zpscs8v.jpg.html)

Third pic shows start or re-assembly:
http://i1201.photobucket.com/albums/bb351/glynnm1945/LCTb_zpspftwfrmm.jpg (http://s1201.photobucket.com/user/glynnm1945/media/LCTb_zpspftwfrmm.jpg.html)

Fourth pic shows assembled steel parts:
http://i1201.photobucket.com/albums/bb351/glynnm1945/LCT_zps8tgr21qi.jpg (http://s1201.photobucket.com/user/glynnm1945/media/LCT_zps8tgr21qi.jpg.html)

It's been a "longer than I anticipated" process but the results are good.

[Whiterabbit]

I'm about to attempt my first try at rust bluing. I have been reading up on it as much as I can find. Most instructions say, bring to a 320 finish. This seems like it may be a little rough. I was thinking that maybe this is necessary to start a good foundation? Would it be wrong to bring it down to a smoother finish?

IMO 320 might be too much. I started with 400, thinking much the same as you. got a nice 400 grit polish then went for it. The color does not take as well, and as the gun blues, you are carding which will by design further polish. What you end up with is a gun that is not as deep or dark as it could be.

Remember, carding is part of the polishing!

So, IMO, if you can get a 280-300, so much the better. I din;t know about 240, that might be a little too rough. But if 320 is all you can find, make it so your barrel is PERFECT with that grit. All scratches concentric, all 320 grit depth. Then go for it.

I guarantee you'll bee far, far smoother than 320 by the time you card off all the flash rust on the surface, leaving nothing but your deep blue. And you won't get it (as) deep if you start with 400.

[BrentD]

White rabbit, I'll disagree with that 100%

I don't know how you measure depth objectively, but I'll put a 1000 grit polish and rust blue up against any 320 grit blue for being just as "deep".

[Whiterabbit]

Perhaps I mis-wrote, perhaps better to say that the bluing seems thinner. gets thin, almost (but not quite) as though you can see through the bluing to base betal, like a blue tinted glass coating.

If you still disagree with me, I have nothing left to stand on.

[BrentD]

What you are describing is a poorly done bluing job, not an overly pre-polished bluing (there is no such thing as over polishing).

[oldred]

I have to agree with WR on the color as my results were similar, I too have tried 1000 and even 1200 grit and even a buffed shine with exactly the depth of color results he was describing. I have tried this with both "Express" blue (Mark Lee) and slow blue (Pilkington) and honestly the end result was no smoother but there was notable difference in depth of color, maybe some would prefer the shade that resulted from the finer finish but I didn't care for it. Also it's notable that most directions for most formula recommend against a really fine grit, I think Laural Forge is an exception to this but even they suggest using a courser grit while mentioning that finer grits can be used if preferred.

[BrentD]

You guys need to rethink how you are doing your bluing if you want a good deep black. Something is wrong - most likely not enough coats. Final color has nothing to do with polish. Here are three barrels I just photographed here in the basement to prove my point. Event though an indoor shot with a cell phone camera, you can see a decent sheen and deep color to each one. Each was polished to 800 or 1000 grit. They are match rifles - which means they get used and abused a whole bunch. The top two, in particular, have traveled thousands of miles to countless matches all over the country and been through rain, dust storms and a ton of rough handling and yet, their barrels are black as coal, just as they were when they were brand new.

Properly done, you can have a pretty nice shine AND a very well protected, dark bluing. What brand you use for a solution is the least important part of the whole process. After all, rust is rust.

http://www.public.iastate.edu/~jessie/PPB/Borchardt/3%20rust%20blued%20rifle%20barrels.jpg

[BrentD]

Here is another picture. Admittedly, the pictures are poor quality but the differences are still evident.

I added another rifle for comparison. The new rifle, at the top of the pile, is a poorly polished (600 grit) barrel that has much less sheen than the others. Like the others, the bluing is still black as can be. This is a hunting rifle so it lives a much easier life than the match rifles. Nonetheless, it has been carried for weeks in the back country of Wyoming and Montana and its blue is holding up perfectly. It just doesn't look very good.

http://www.public.iastate.edu/~jessie/PPB/Borchardt/4%20rust%20blued%20rifle%20barrels.jpg

[oldred]

I tried various ways of getting color and gloss and while I did indeed get a good gloss with the high polish it was no better, little different actually, than the coarser grades. There was that notable difference in color (on mine anyway) but as far as gloss it seems to be about the same. The color I ended up may have been appealing to some and maybe even what they were looking for but it didn't suit tastes.

Basically I use rust blue for the unique dark appearance of rust blue and for a deeper "blue" high gloss polish I buff and hot blue.