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Flophound
08-23-2020, 07:20 AM
Hi all,
I've recently gotten into doing some light gunsmithing being stuck at home for these past few months. I'm mostly using hand tools and a drill for my work. Very much in the crawl phase of the crawl-walk-run model.
I'm any event, I have a .45acp conversion cylinder made for a Pietta 1858 New Model Army. It's just a hair too long to fit and function in my Uberti 1858 New Model Army Carbine. I have a whole whack of files that were my great grandad's, but I've noticed a bias, so to speak in filling when filing with my dominant and, and non dominant hand.
Is there any way to ensure an even draw of a file, or perhaps, is there a different method for reducing a few fractions of an inch from the front of the cylinder?
Thanks for your input,
Flop

William Yanda
08-23-2020, 08:08 AM
If there is no protrusion on the front of the cylinder, could you not rub it on abrasive paper mounted on glass? I don't envy you the task of removing even a few thousandths by hand, however you do it.

Bent Ramrod
08-23-2020, 12:40 PM
With files, you need skill, which comes from practice. Lots and lots of practice. If you can get a chunk of metal and some spotting compound, practice filing on that until it just slides through your cylinder window and the filed surfaces are flat.

The spotting, testing, filing, respotting and retesting will likely go on a while, and will take at least as long on your cylinder, which you only get one chance on.

This is really a job for a lathe and a carriage stop. I fitted a .44 Spl cylinder to a .44-40 Single Action this way. The cutting took maybe 60 seconds tops, but the setup, checking and rechecking consumed several hours.

Flophound
08-23-2020, 03:31 PM
If there is no protrusion on the front of the cylinder, could you not rub it on abrasive paper mounted on glass? I don't envy you the task of removing even a few thousandths by hand, however you do it.

I'll give that a shot. Thanks for the suggestion!

Flophound
08-23-2020, 03:34 PM
With files, you need skill, which comes from practice. Lots and lots of practice. If you can get a chunk of metal and some spotting compound, practice filing on that until it just slides through your cylinder window and the filed surfaces are flat.

The spotting, testing, filing, respotting and retesting will likely go on a while, and will take at least as long on your cylinder, which you only get one chance on.

This is really a job for a lathe and a carriage stop. I fitted a .44 Spl cylinder to a .44-40 Single Action this way. The cutting took maybe 60 seconds tops, but the setup, checking and rechecking consumed several hours.

Getting a metal lathe (and learning how to use it) is definitely on my list. Drill press, too for that matter.
Trick is gonna be convincing my better half that they're worth the investment.��

45 Dragoon
08-25-2020, 01:32 PM
Dupp.

45 Dragoon
08-25-2020, 01:33 PM
Dupp.

45 Dragoon
08-25-2020, 01:37 PM
Some 220 grit sandpaper on a glass surface works well. You can graduate to 320 grit and finish with 800 - 1200 grit for "pretty" (you won't even have to polish it!!)!!!
Work the cylinder in a figure 8 pattern and rotate 1/3rd every 10 cycles or so . . . When done, you can use the high grit 1200 stuff to pretty it up by just screwing it back and forth and still using a 1/3 rotation spin. . . you can do it.

Mike

Ozark mike
08-25-2020, 01:38 PM
Id find someone with a lathe before I'd tempt that one. This is coming from someone who will take a grinder and gas weld just about anything.

45 Dragoon
08-25-2020, 01:46 PM
[QUOTE This is coming from someone who will take a grinder and gas weld just about anything.[/QUOTE]


Must be talking about you I'm assuming ?

Mike

KCSO
08-25-2020, 01:48 PM
Bent ramrod has it right, when I was learning I was given a chunk of steel and told to file it into a square and given a machinists square to check it. It took me days but in the end I had a small square and a lot of practice. After the surface is clean coat it with dykem and check your progress as you go. inish with oiled wet or dry on a sheet of glass or a surface block and work it in a circular motion.

45 Dragoon
08-25-2020, 01:54 PM
Figure 8 is better than circular.
What I mean is a fig. 8 pattern is more consistent maintaining a flat surface than a circular pattern. That comes from an aircraft machinist . . .
Mike

Ozark mike
08-25-2020, 01:54 PM
[QUOTE This is coming from someone who will take a grinder and gas weld just about anything.


Must be talking about you I'm assuming ?

Mike[/QUOTE]

Yes i was talking about myself. Had somebody stop by with a old goldwing carburetor awhile back that had the float post broke off so i welded it up for him with the torch.

45 Dragoon
08-25-2020, 02:01 PM
Must be talking about you I'm assuming ?

Mike

Yes i was talking about myself. Had somebody stop by with a old goldwing carburetor awhile back that had the float post broke off so i welded it up for him with the torch.[/QUOTE]

Lol!!!! I think I know you !!!!! Lol (I know what you're talking about!!)

Mike

Backwoodsdave
08-28-2020, 05:45 PM
I recently fitted an extra pietta cylinder to my uberti 58 nma, it was jus a few thousandths long, I did mine on the lathe but it could easily be done by using the sanding/lapping method mentioned above, I would advise using a cloth backed emery sheet on a flat surface, and use it wet, kerosene, diesel fuel etc, I’ve lapped many parts like this in the past and it gives a nice finish, most auto parts stores or home improvement stores sell it by the sheet in various grits.

bedbugbilly
08-28-2020, 10:01 PM
Just curious on how many thousandths need to be removed? Just thinking out loud as I know the OP is limited on tools but if it weren't for the locating pin on the breech end of a Howell for the cap, seems like the job could easily be accomplished on a surface grinder with a goo magnetic chuck plate. Anyone know just what the difference isn in the length a Uberti versus a Pietta for the 1858s?