Question: Best Metal Finishing Files? Cold Blue?

[Doc Mark]

I'm about to start my first firearm and I need to do some surface smoothing first. I've heard about "Swiss Cut Files" and "American Cut", but I've never seen an explanation of the differences or which is better for what purpose. How can you tell a Swiss Cut from an American Cut file? I've got a large box with quite an assortment of wood and metal cutting files that belonged to my father. I have several labeled "Mill Basta*d". I would like to know what files you use to prepare your firearms after stripping off the bluing. I do have a good assortment of flat stones to use after the files remove the bulk of the casting pits.

That brings up my next query. Since I'm doing my first gun work on a cheap 9mm that I already owed, I don't want to spend a fortune on rebluing. Please tell me that there is a brand of Cold Blue Solution that will give a reasonable finish. I know a proper hot blue job is the best, but is there any way an amateur can get good results at home?

Thanks for your imput,

Mark

 

[thefox]

blueing

Hi Mark!

Brownells have a variety of cold blue on the market. It's been quite a while since I have used them, but I got good results. I believe the name was perma-blue. They also sell a very good rust blue that works great and is not all that hard to do if you just go by the directions to the letter. I have used the rust blue on doubles, and got very good results.

Bryan Clary

 

[dclevinger]

Doc,

Swiss pattern files will generally give a smoother finish than an American pattern in the same cut. I use a draw file on the flats. It is a thick file with no handle and doesn't flex like a standard one does. Be sure to use file chalk and clean the teeth every stroke or two. Otherwise you'll end up dragging a cutting across the piece which will make a very nice gouge.

I haven't seen a cold blue that will give a good durable finish. It doesn't really blue the metal, it's more of a staining process and gives very little protection against rust. Many 'smiths will give a discounted price for dipping parts if they are already prepped. Few will offer any guarantee if they don't do the prepwork, however. You might check with some shops in your area and see what they say.

If you are going to put all effort into cleaning up the metal and engraving it, you may as well put a good finish on it and really have something to be proud of.

Just my 2 cents.

David

 

[Tim Wells]

For draw filing the flats on the barrel of my 73' Winchester and the reciever I used a new mill ******* and some sidewalk chalk I stole from my kid.

I wouldn't fool with the Birchwood Casey "Perma blue" found in the wallyworld; I'd get a bottle of Oxpho Blue from Brownells. Birchwood/Casey used to have a version called "Super blue" that sat right next to the Perma blue that made a blacker blue but I haven't seen any of that in years.

If there is a Cabela's or a good gun store local to you they may have some Oxpho on the shelf so you can save any hazmat fee that UPS slaps on to shipping from Brownells.

Make sure before you blue it that it is absolutely, spotlessly clean. It wouldn't hurt to heat the gun up a bit before you spread it on, it'll work better that way and coat more evenly. Holler if you need help.

 

[fegarex]

What Tim and David said are good tips. Many people that blue will offer a decent price if the metal is finished right and all is needed it the dipping steps. The Brownells cold blue and the "super blue" are the better versions but both of them are much like trying to paint a car with spray bomb paint cans. Another option would be a French gray finish. Do a search and you find a few options on how to do this.
On draw filing...
A few years ago I tried something that breaks all the rules on this but seems to work for me.. Use a lube like WD-40. Like Tim, the traditional method was to chalk the file and keep out the chips. For some reason the WD-40 really works for me. Your mileage may vary, all disclaimers attached.....

 

[Tim Wells]

Rex,
Do you spray the file or keep a puddle of it on the steel? Yet another use for that Water Displacement formula #40.

 

[fegarex]

Tim,
I spray it on the steel. You'll need to wipe down the file and metal from time to time but it seems to "float" the chips and keep them from scratching. Other oils seem to work as well but WD-40 was handy and cheap. I've used Tri-flow just because it smelled better.
Again, old school metal finishers will have a cow with this method but for me it seems to work.

 

[Kevin P.]

Mark I have no experience with guns, but some with metals.
It sounds to me if one gets large chips, the file is too coarse. It's better to start with a finer cut and go to something coarser if the finer doesn't do it.
As has already been mentioned Swiss files will give a smoother cut than American and come in a #6 cut which is very fine.
The best tip I can give is Gesswein: Catalog #48 (www.gesswein.com). #48 is their 'Mold and Diemakers' catalog. It has tools I've not seen elsewhere outside catalogs that weigh 10#. The printed version is better than online because it gives info such as the difference between American cut and Swiss cut.
They have lots of abrasives and they're nice people to deal with.
Kevin

 

[M. J. Atkinson]

Mark, you won't need to draw file unless the surface is pitted. You polish with buffing wheels or hand polish with various grades of abrasive paper or cloth. Brownell's has very good info available on polishing. Oxpho-Blue can give you an excellent, long wearing finish, maybe notthe equal of hot caustic blacking or a rust blue but quite acceptable. Try this method: After polishing, degrease thoroughly. I use brake cleaner (outside) as it doesn't leave a residue. Put a small amount of Oxpho in a dish, bearing in mind that any left over will be contaminated and must be thrown out. Warm the metal till uncomfortable to touch. Using a piece of 4/0 steel wool, apply the Oxpho to the surface, rubbing it on evenly. Wipe off the excess with a clean rag till dry, then buff with 4/0 wool or a baby soft wire brush. If not dark enough, reapply. If the color is not even, the surface was not clean. Cleanliness is the secret to blueing, as it is to soldering. Here endeth the lesson.

 

[pilkguns]

Whatever file you use, before you start to drawfile with it, you need to run it a few times across a nice flat stone, or diamond wheel, to make absolutely certain that all the teeth edges are at exactly the same height

 

[Dave London]

Also I would practice on some junk first, draw filing is harder than it sounds

 

[monk]

get a piece of junk metal and test your files. files are like girls; each one has a way all its own . different feel, slightly different cut,. 2 can appear exacty the same but will behave a bit differently in the metal, esp used ones. there's no such thing as an old file. they can always be re-tempered and made into other useful things, scrapers, burnishers, punches, wood lathe chisels, gravers, etc, etc. some books claim an old file cant be converted into a wood lathe chisel. hogwash. if it's properly re-tempered, they make great chisels. it's all in knowing how.