Polishing

[Zonie]

We have all been there. You know, got a kit of some kind and found that the finish on it doesn't even come close to what we want.
So, out comes the files, the wet/dry sandpaper and hours later we have something that looks not much better.
Some of us managed to work our way down to the 600 or finer grit paper but it still has a satin finish. From here on we tried everything we could lay our hands on and finely managed to get a nice polished finish.

To finish a rough casting a series of steps needs to be taken. These consist of rough filing/grinding, finish filing, sanding and polishing. Nothing can be skipped as each process depends on the completion of the previous one if it is to give the results you desire.


The sanding should be done in steps starting with the course paper and working down to the fine grit paper.
I recommend working down to 600 grit although power polishing requires only going to the 400 grit.

Once the surface is sanded to the 600 grit level and no traces of the rougher grit is left, you can start polishing.
I suggest a course cloth material such as denum although heavy cloth like you use for patching will work well,
For a polishing media, start with something made for cleaning Copper bottomed pans. This is rather course, so if it seems to roughen your sanded surface, go directly to some of the Brass Cleaner your wife has under the sink. Better yet, buy your own.
This Brass Cleaner is just right to finish your guns furniture.
Keep the rag damp with polish or water. When the surface seems to be as good as it gets you may want to use Silver Polish as the last step. The Silver Polish will make the surface bright as a new mirror.
When changing polishes, change rags too. You don't want any of the courser material on the polishing rag.

There has to be an easier way!

For the lucky people with a bench grinder there is an easier way, at least for the last steps of the process. That way is to use a disk polishing wheel and an abrasive.
My local hardware stores carry these items made by a company called Dico.

The disks have an adapter included which is made for a 1/2 inch shaft and they are safe to use up to 4500 RPM for a 6 inch disk. If your grinder has a 3/8 dia shaft or runs faster than 4500 RPM, I would not recommend trying to use a 6 inch diameter disk. They also make a smaller disk which can be run faster but in general, the 6 inch will work on almost all bench grinders.
Dico also makes an adapter for a electric drill and it's worth a thought but because the drill will be running much slower, it won't work quite as well as the bench grinder.

Although using one of these disks and abrasives does remove material, don't count on it removing file marks or deep scratches. It usually just makes them more noticable or worse, the disk will create a rippled surface if used to try to remove them.

WHEEL/DISK:
I suggest getting a 6 inch disk and I prefer the spiral stiched one. The single stich will work, but it seems to wear out faster. The cost for one of these is between $6 and $10, so it won't break the bank.

ABRASIVES:
Dico offers 7 different abrasives and I have tried them all.
That said, to cut to the chase I only use 2, and of these only one seems to do everything well. (These abrasives cost between $3.50 and $4.50 and will last a long time.)

The two I use are STAINLESS (SCR)and CHROME ROUGE (CR1). Of these the STAINLESS (SCR) does everything I need on both Brass, German Silver and Steel. Buy it and you will need nothing else.
Stainless will reduce the polishing time from several hours to a few minutes.
If you aren't satisfied with the Stainless, switch to the Chrome Rouge. NOTE: Do not apply different abrasives to the same wheel. If your going to use the Chrome, you need to buy another disk, just for that material.

POWER POLISHING
WEAR GLASSES AT ALL TIMES WHEN POLISHING!!
After mounting the disk, start the machine and apply some of the abrasive to the spinning wheel.
The first application needs to be moderatly heavy.

Holding the part against the disk with a light to moderate amount of pressure, Move the part back and forth and Rotate it so the disk isn't polishing the surface in one direction only. The very best polish will be the result of the disk working in many different directions on the surface.

ALWAYS polish from the surface towards the edge of the part.
If you polish from the edge to the surface it will round off the edge and after it has done that IT WILL THROW THE PART AT YOU WITH GREAT FORCE!!!! After 9 years, you would think I would learn this lesson but it seems I always try to press the limits and POW! the part that was in my fingers is gone!
Not only is this dangerous but sometimes it is damn hard to find out where it went. It can also bend or damage the part so remember my warning.

As you polish the action will seem to slow down. When it does, apply a LIGHT coat of abrasive and continue polishing.
If you use the "more is better" method and apply too much polish the disk will not polish as well. It will in fact just coat the surface with the abrasive and stop cutting. If this happens, the only method I have found is to polish something which is just laying around until the extra material is worn out and wiped off of the disk.

By the way, remembering that you must polish from the surface towards the edge try using this disk and Stainless on your chisels. It will hone them to a mirror bright razor blade sharpness in seconds! I am talking about so sharp that you rest the blade parallel with the surface of your fingernail and move the chisel forward and it starts cutting into the nail sharp!

Another thing Stainless does well is to polish the nose of the lock sear and the tumbler notch the sear rests against when the lock is cocked. This will make the hammer release so smooth you won't believe it BUT, remember your just lightly polishing the surfaces, do not try to remove ANY materal or you may make your gun unsafe to use.

Happy Building!!

 

Brass is Easy!! Personally I never liked shiney brass,, it reminds me of richy,richy,fancy shmancy that never gets used,, If all them guns used Brass trimin's I'd be in heavin! I lay a "patina" on brass with my first cleaning patch, I like the look of a "working mans gun". But that's just me,,,I mean, with all respect,and it's a darn good post,,but,,,,,,,,,,

tell me,,How dow ya take sand cast iron parts,,too at least a good "browning" finish?? How do ya take that "seam" off them parts?? Leave'm raw?? Hammers,,Cock,,Jaw,,Frizzen,,,Trigger Gaurds,,Butt plates,
Iron don't Polish so easy, any tips fer iron besides power tools? aka; bench grinder pads an rouge??,,,,,

 

[Darkhorse]

Another good way to polish brass is to use a dremel tool with the polishing attachment and rubbing compound. While not as efficient as the bench grinder it will allow you to get into the tighter areas.
When the gun is finished, I want everything as finely polished and finished as possible. If it is a hunting gun, that is the last time the brass will be polished. After shooting it for awhile and handling it with black powdery hands, the brass soon takes on a dull patina.

The seams in cast steel (flash) can be filed off, then sanded. The same polishing wheels and compound, such as a jewelers rouge stick can be used on steel as used on brass. You may not want it quite as slick and polished if you are going to brown it. Stopping with about 320 grit should give you a smooth finish that also browns evenly.

 

[Zonie]

Gotta agree with Darkhorse.
On steel parts the only real difference is it is a LOT slower.
I always remove the casting parting line. IMO failure to do this chore rates up there with failure to sand the stock before finishing it. Yes it is a PITA.
To remove these cast ridges, I usually use needle files in the tight areas (like where the underjaw of a flint cock meets the shank. Where there is room, I use a Dremal grinder with a sanding drum mounted on a 1/2 inch diameter expanding plug. This is one of the best high speed grinding tools I've found because you can buy the little sanding drums in 3 different grits at a fairly low price. Brands like ACE have their own drum replacements and they work very well, even on steel.

If your going to brown the steel, I would stop at 320 or 400 grit paper. The 320 will give a better looking matt surface when browned.

As for high polished brass, german silver or sterling silver, I like it on the guns I build (as you may have noticed in the Photo Forum area).
Different strokes for different folks, as they say.

 

[Ohio Joe]

I see we all have pretty much the same idea when it comes to polishing, we just approach it in different ways. I like the hand tools, files, sandpaper, emorycloth, and steel wool on a dowel. I use my dremel with sanding drums, and for pre buffing/polishing with the compound. I like to get the person I am building a rifle for involved in the polishing process, and a few other areas. This gives them the personal feeling of helping to build their rifle and a feeling of accomplishment once it's done. Other areas I have them help out are; First sanding of the stock once I've shaped it. First coat of waterbased stain when ready. Bluing or browning the rear sight. The little things you can fix or go over if needed. Building muzzleloaders are fun and corrupting someone else into learning how to build muzzleloaders is keeping the tradition alive.

 

[crockett]

I noticed you went down to 600 grit. You can get finer grit at auto parts stores. I get 1000 grit, 1500 grit, and 2000 grit. This stuff is so fine that the edge of the paper may stratch the brass so I fold the paper so that no scissor cut edge contacts the brass. I also use a polishing compound called green chrome. I believe I got it from Brownell's. I use it for knives but it works well on brass. I'll take either cloth or leather and put a little oil on it. The oil helps pick up the polish. I'll then rub the block of polish with the oiled cloth or leather and then hand rub the metal, in this case brass. You can go one finer step using the same approach with red, jeweller's rouge. I back the cloth or leather with a stick to keep surfaces flat. You should get a perfect, mirror polish. Good luck.