Grit for pre-blue polish.

D

dahermit

New member
As a project, I am going to have an old handgun re-blued. I will do all the polishing and prep, the gunsmith is going to charge me $40.00 for the blue.

I have a metal working background, so I feel confident in my ability to produce the required flat, ripple free surface, sharp corners, no dished out holes, etc. However, I am not sure of how polished the gun will have to be. I have started with 400 grit wet/dry automotive paper. The question is, what grit should I use for the final polish? Is 1000 grit enough or should I go with as high as 1200 or finer?
 
How about asking the gunsmith what he recommends for the final finish before bluing and what he uses to obtain said finish
 
Why, when I have access to many good gunsmiths with experience here? He is just one guy, I want as broad of information as possible.

However, one good reason is that I am a High Functioning Asperger's Syndrome person who would rather deal with typed text than to have to deal with people Vis-a-Vis or on the telephone.
 
What gun and how shiny do you want it?

I have seen 400 and 600 grit advertised as "factory finish" and "mirror finish "with everything from 1000 to 2000 grit.

Since you are doing the polishing, you can stop when it gets where you like it. The blued finish will be exactly as smooth as the bare steel you have him "dip."
 
It's according to which brand of gun you have, as to the finish. Most manufacturers stop off at 400 grit, but some go on up to 555 or 600 grit, which is a mirror finish. 400 grit is close to mirror, and is what the model 12 Winchester used on the receiver at the factory.

If you have access to Brownell's Gunsmith Kinks books, this is covered in volume one. You will at least need to have a loose and stitched wheel, and polish running from 120, 240, 400, and maybe 555 or 600. Also, you can't mix polish on a wheel as you go up. I would use 120, and 240 on a stitched wheel, and finish with 400 on a loose. You may want to use grit cloth on the frame, by hand, using a hard and flat backer board, to keep the corners sharp, which is more time consuming, but in reality, a revolver frame is so small, it doesn't take long, unless its badly pitted. Also, I think some of the grit sizes are different between cloth and polish, in that the numbering system is different, and the sizes don't match. It is according to the manufacturer. You would want to check this out before doing it.
 
That which I have already done with 400 grit is nowhere near what I would call a mirror finish, so it is obvious to me that I want to get it a whole lot finer. I will not be using any cloth wheels but will be doing it all by hand (all flats done with flat backers). Inasmuch as the gun, (old Colt P.P. Special) has no collector value, I want to go with a more spectacular degree of finish. It is after all, a "keep busy, Winter project" of no great importance.

I know from previous industrial experience with plating, that the quality ("depth") of plating (and bluing), is directly attributable to the quality of the metal polish. So, I am going to go for it.

I have purchased some more 400 grit wet or dry, and some 1000. But I saw that they had some up to 2,000 grit, so it got me wondering.

For the ultimate in metal polish in the past, I have used a piece of rough-out leather and Jeweler's Rouge. So, I may end up with that, but wanted some input on the subject.

Thanks for the input.
 
I think the difference in the paper grit to polish grit is in ANSI designation as compared to screen size, and the numbering is different. What would be 400 grit polish, would be higher in paper and cloth sheets. I think that Caswell has/had a PDF on this, and it may be under plating or anodizing instead of polishing. It may be in volume 1 of Gunsmith Kinks, also, but I can't remember, without looking it up. I have read about similar when sharpening and honing knives and plane blades. 555 or 600 grit polish will leave the surface like a mirror, and that is generally the highest anyone takes a firearm. I don't do many of these, since most people don't want the reflective glare in the light, so I do either a hunters finish with 240 grit, or a finer 400 grit.

Grit sizes:

http://www.fine-tools.com/G10019.htm

.
 
It depends on whether you want a mirror-like finish or a factory finish.

Factory finishes are not very "good"; the name of the game is production, not shine, and in fact many hunting rifles are deliberately made with a dull finish. As Dixie Gunsmithing says, gunsmiths will often use up to 600 grit or even finer, while factories may go with 160-200 grit. (There are exceptions, Weatherby being one.)

The result is that a very high polish will look good (if that is your preference) but won't look "original". The importance of that is a matter of personal preference.

Jim
 
Well, you started with 400 grit, which is where you should finish. I started out polishing guns for bluing 34 years ago. What I was taught was:
* Start with 150 on a hard sanding block until all pits, scratches, and dings are gone or blended in. The metal will be a light grey color.
* Move to 220 grit on a hard block to remove all sanding marks. All sanding grain should be in the same direction. Surface of the metal is bright but non-reflective. If you buff this metal, it will look like most factory finishes, shines, but rough.
* Move up to 320 on a hard block to remove all sanding marks. By now, the metal should have a shine to it. All corners should be sharp, all flat surfaces should be flat, all round surfaces should be smoothly radiused. Lettering should be sharp and legible. When buffed, this metal has a shine to it. This is like older Winchester finishes.
* The final step is polishing with 400 grit, in most instances. Again, all grain runs in one direction, all corners are sharp, all round surfaces are round. At this point, if the polishing has been done properly, the metal has a glow. When buffed, it is shiny. This is like Browning or Weatherby finishes.
* If you want a truly superior finish, you can move into 600 or even 800 grit, and once polished you can wet sand the metal. At this point, if you buff the metal lightly, it will have a mirror finish.
 
* Move to 220 grit on a hard block to remove all sanding marks. All sanding grain should be in the same direction. Surface of the metal is bright but non-reflective. If you buff this metal, it will look like most factory finishes, shines, but rough.
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This is precisely what I have heard for "factory" finishes, and what I've seen of "220" finishes.

(I use quotation marks, because the gunsmith that I used most recently just uses a wire wheel for his "factory" grade finishes. Sounds like it could go very badly, but a Marlin that he 'wire wheeled' for me looks great.)
 
All great advice...
I am also removing rust and prepping for reblueing if required
Got a Contender 7x30 waters barrel 14" lg and was told to soak it in PB blaster
then use #0000 steel wool. How does this stack up to the grits listed above?
Also only have #000 on hand at the moment
 
Steel wool won't remove metal-only rust. To remove pitting you need to lower the surface of the steel. This requires abrasives like silicon carbide sandpaper and polishing wheels.
 
FWIW, factories use hard wheels, not the soft wheels used by many gunsmiths. That (and skill) is how they keep from rounding corners and dishing screw holes and markings. They also use shaped wheels. For example, S&W has wide hard wheels that are shaped like most of the bottom of a revolver frame, including the trigger guard and the space behind it. All they need to do is to hit the wheel, rotate the frame a couple of times, and the job is done.

Hard blocks (wood or hard rubber) can be used instead of a hard wheel, but care needs to be taken; for a flat surface, it is usually better to keep the block firmly on the bench and move the work rather than the reverse. For a really neat job, protruding parts (like the spring tunnel on a 1911) can be removed before polishing.

Jim
 
For a really neat job, protruding parts (like the spring tunnel on a 1911) can be removed before polishing.
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I am amazed at the number of allegedly deluxe pistols that do not have polished frame flats. It is a lot easier to shine up the slide flats but the frame is more trouble so you can pay a lot of money and still get a mismatched appearance.
 
It all depends on how shiny you want it. I prefer a semi matte finish on a hunting rifle. While a highly polished rifle looks great in your den, it will make a flash that can be seen for a mile if the sun hits it, announcing to every deer in sight that a connoisseur of fine rifles is coming.

One note: Everything depends on the quality of the polish job. Bluing hides nothing, it just changes the color of the metal.

Best of luck with your project.
 
A light touch with red jeweller's rouge and a cloth wheel.
"...not sure of how polished the gun will have to be..." The quality of the bluing(really blackening) job depends on the prep work. As mentioned, bluing hides nothing. Any 'disfigurement/flaw' will be seen. If you want the best bluing job, a mirror finish is required.
 
For what I was taught, and do here, as a hunters non-glare finish, is to remove the old bluing, and any pits, leaving all corners sharp, with 120 grit polish on a stitched wheel, then finish that by polishing at a 45 degree angle, with 240 grit on a loose wheel. You start at 45 degrees to the gun with the 120, and then by turning 45 again, for the 240, it leaves straight lines on the steel, and parallel to the gun itself. It leaves a nice brushed look that's actually better than some finishes you see on lower cost firearms. The glare from reflected light is minimal. It takes a lot of practice to keep sharp corners, where you have to have a light touch, and always polish toward the edge, as if sharpening a knife. There are many tricks in polishing, such as cutting and coloring passes.

To get a true non-glare finish, one can bead blast the entire gun. I don't do many of these, but do blast what was blasted at the factory, similar to Winchester model 12 magazine tubes, etc.
 
If I really wanted it to look high polished, I would start at 120-150 range until flat both directions....

220 to get it smooth both directions....

320 to ease the jump to 400...same work as 220....probably would finish wet and with med to old paper

400 both directions dry. Then new paper 400 wet both directions. Then wipe and oil and wipe again...how does this look? It should look like a polished flat on a modern gun with polished flats.

Then I would do the same at 500 and 600.....you will need a poop ton of paper to keep cutting at 500 and 600. Forget the dry sanding too.

You could maybe go 800 & 1000 to get a bit more since you say you won't use a wheel.

After this, sanding looses its value as you have a very flat and very polished surface....also, the paper fills up quick.

A firm wheel or cloth with some fine 1000 grit ish polish will extract the last bit of gloss.

1500 plus grit paper are for see through type finish like paint, glass, headlight lenses.

The really hard thing to do is completely clean up the previous grits sanding marks before moving on. This is the most important tip this thread gives!
 
"If you want the best bluing job, a mirror finish is required."

That depends on the definition of "best"; a brilliant shine that will blind every animal in the county might not be in a hunter's best interest.

Jim
 
If you want the best bluing job, a mirror finish is required.
Click to expand...

That depends on the definition of "best"; a brilliant shine that will blind every animal in the county might not be in a hunter's best interest.
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While I'm generally a matte/satin blue type of guy, I will admit that the only highly polished finishes that I've ever seen "flash" were those on octagon rifle barrels. As the flats moved around and caught the sun, they gave very distinctive and attention-grabbing flashes ...like an airport beacon.

The most notable instance was with a hunter over 1/2 mile away, hiking just below the crest of a ridge. As his rifle swayed back and forth on his shoulder with each step, that octagon barrel strobed like it was part of a laser light show. Not only could I see the hunter from my position, but I could see the antelope on the other side -- snapping their heads up to look at the flashes, because the top six inches of the thirty inch barrel was occasionally exposed to them.


Round barrels and even action flats have never caught my attention...
 
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