Short Cylinder Arbor Fix

[tpelle]

I'm still working on my Pietta 1860 Army. Reading everything I can find (there's so much more information that one can refer to, thanks to the 'net - almost too much information!). I ran across the two .pdf's on here about tuning Pietta revolvers. I did the cylinder arbor length test, and mine came up short!

Further googling turned up a couple of fixes: One fix is drilling and tapping the end of the arbor for a depth-setting screw. Another is building up the end of the arbor with weld or with solder, then filing to fit.

I'm wondering about building up the end of the arbor with J. B. Weld (I know. Not very authentic.), then filing the J. B. to the length needed?

Any other ways to fix this issue?

Or should I just not worry about it, and go shootin' instead?

 

[Smokin_Gun]

Yeah... if your arbor ain't bottomed and you are in need of eliminating barrel wobble , shim it make a beer can shim to place atop the arbor as you slide the barrel over it.
Has worked on my old pietta 1860 for a couple years now.

 

[madcratebuilder]

You could drill a small hole in the end of the arbor and use JB to build up the end, then file to fit. The best way is the drill out the arbor retaining pin, remove the arbor, and then weld the arbor end and re-machine it on a lathe.

I machine a spacer then I loc-tite in the barrel lug. I thread the spacer 6-32 and use a rod to insert and remove it until I get the correct fit.

 

[tpelle]

It looks like the cylinder arbor is about 2-cents short. What I mean is, if I remove the cylinder and place the barrel on the arbor about 90-degrees off, the bottom of the barrel overlaps the frame about the thickness of two pennies - maybe slightly less. I'm thinking I may experiment with making two shims out of a couple of "Honest Abes", stoning them to the proper width, and seeing how that works.

I can't find any pin that looks like it's holding in the arbor on this Pietta 1860 Army.

 

[Jim Watson]

There was an article in the Cowboy Chronicle about using a Dillon locator button as an arbor spacer. Drill a little hole in the end of the arbor to take the stem of the button, file it to the right thickness, and loctite.

 

[tpelle]

Just as an experiment, I'm gonna try a J. B. Weld fix. I degreased the end of the arbor, wrapped it with masking tape so as to make a kind of form on the end, and filled it with J. B.

In a few hours I'll strip the tape off, and go to work with files to form the built-up area on the end. I think I'll file it with a little taper so that the J. B. is slightly smaller than the hole in the barrel. That way, if the J. B. cracks off, it won't remain wedged in the arbor hole (But as I write this, I wonder why I care. If the J. B. weld shim breaks off, it will just stay in there and will still work as a shim.)

If the J. B. Weld eventually comes off, no harm done. Then I'll try something else.

When the whole shim thing is done, I'll stone the wedge (if needed), then I'll adjust the screw on the left side to set the depth that the wedge gets inserted.

 

[madcratebuilder]

I can't find any pin that looks like it's holding in the arbor on this Pietta 1860 Army.

Look under the hammer at the back of the recoil shield. You should see the end of the arbor, just above the arbor there should be a hole that is drilled half in the arbor, half in the frame. Just about all steel frame guns well have this. Many brass frames well not have the pinned arbor. It's purpose is the keep the arbor from turning.

If you ever drill one out for arbor repair, when you go back together, tap it and use a set screw instead of a pin.

When the whole shim thing is done, I'll stone the wedge (if needed), then I'll adjust the screw on the left side to set the depth that the wedge gets inserted.

I would recommend not stoning the wedge if you can, if you can get the nose of the wedge flush with the side of the barrel lug, that's GTG. I leave the wedge screw fully screwed in.

 

[tpelle]

OK, here's what I did. First, before I got too far along, I abandoned the J. B. Weld idea. But I found something better! Out in the shop, I had a pack of 1/8" aluminum Pop-Rivet washers. When I saw 'em, my calibrated engineer eye told me that they were just about the right size. Turns out, they are just a smidgen smaller in diameter than the arbor diameter, and two of them stacked together were just slightly more than I needed. A few minutes - seriously, maybe 10 minutes - with a file and an Arkansas stone had them exactly the size I needed.

If I drop the two washers in the arbor hole in the barrel, then slide the barrel on to the arbor 90-degrees out of rotation, when I rotate the bottom of the barrel down to the frame, the barrel just drags against the front of the frame. IMHO, this is just about as perfect as it gets!

Re-assemble the pistol with the cylinder in place, and the barrel gap at half-cock is just the thickness of a folded-over piece of printer paper.

Tomorrow I think I'm goin' shootin'!

 

[mykeal]

Good solution. However, the aluminum washers may peen and lose a bit of thickness. Don't throw away the spare stock.

 

[grey8833]

Spacer

mudcratebuilder
BINGO.... did exactly the same on my Walker. Good heavens, parallel engineering solutions.

I do agree with the comments that advise using steel. You can hold them in place with JB weld, but make durn sure you clean out the excess before it hardens.

Mike F

 

[Smokin_Gun]

I used a small washer stack in my Pietta 1860 Army two years ago or so ... still bottomed and I use the beer can shim atop the arbor also.