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Bent Ramrod
03-15-2013, 02:08 AM
I have a Filli Pietta 1851 Navy which developed a slight wobble of the cylinder arbor after a couple shooting sessions. The arbor seems to be staked into the frame with a pin, which is ground off flush with the back of the arbor and the curve of the frame. I would imagine removing this arrangement would be complicated. Has anybody else experienced this looseness? Are there any easy means of tightening this arbor up? With the wedge firmly in place, the barrel wobbles slightly,which I'm sure does nothing good for accuracy.

Thanks in advance for any advice.

Nobade
03-15-2013, 08:06 AM
If you are certain it is the arbor and not the wedge needing adjustment, I have had reasonable luck removing the arbor from the frame and applying epoxy to the threads. I had to grab the arbor in a collet holder to unscrew it so as to not damage it, if you put something through the slot it's possible to twist it. Another option is to get a new arbor from VTI gunparts and fit it. I had to do that too, and it gave me a chance to get the shoulder in the right place so it torqued up properly. Too bad the replacement arbors are too short just like the originals, it would have been nice if they were long enough to "file to fit" and not have to put shims in the bottom of the hole in the barrel.

-Nobade

KCSO
03-15-2013, 09:57 AM
Rather than putting a shim in the barrel drill and tap the arbor in front and put in an extension and then file to fit. By the same token is the wedge is lose the same scre can go all the way through the arbor to be fitted to the wedge. If the arbor is loose in the frame I also use J B weld and it seems to hold.

Bent Ramrod
03-15-2013, 05:27 PM
Thanks for the replies. The looseness is the arbor in the frame; the other end seems to fit the hole under the barrel very well when the wedge is tapped in.

Looking at the slot in the rear of the frame where the hammer falls, there appears to be a smaller circle on the edge of the circle made by the arbor, both of which are ground off flush with the frame. I figured this little key or stake is in the frame to keep the arbor from unscrewing. Do you have to drill this out before unscrewing the arbor? Or is it threaded in as well? If so, could I drill a hole in it and unscrew it with an Ezy Out, and then unscrew the arbor?

Nobade
03-15-2013, 08:36 PM
Sometimes you can unscrew it without drilling out the staking, sometimes you need to drill first. Try it and see. I also have been known to replace the staking with a little set screw to hold everything in place but be removable.

KCSO - you're right, that is a good way to do it and easier to fit.

-Nobade

Hellgate
03-16-2013, 01:07 AM
I sure hope you have a steel frame gun. If it is a brass frame the drill will tend to walk off the stake pin into the brass. You might need a drill press to hold things steadt and replace the stake pin with a set screw. Then you can use the JB Weld or strong epoxy to hold the arbor in the frame.

John Taylor
03-17-2013, 11:40 AM
The last one I did was years ago. Made a new arbor out of some pre hardened spring steel and cut the threads a bit on the large side so it would screw in tight, no chance of wobble. A drop or two of loctite so it would not come loose and then cut the wedge slot to fit as well as the length so the barrel would not drag on the cylinder. used carbide tooling to cut spring steel. My feelings about brass frames is they never should have made them in large calibers.

Bent Ramrod
03-17-2013, 10:40 PM
Thanks to all for the advice. This is a steel frame revolver. I think I'll try the JB weld method. Would tinning the arbor threads and heating the arbor and frame for a solder bond be practical?

I had a Navy Arms Uberti pistol many years ago that I abused with hard lead roundballs and oversize bullets and only succeeded in wearing out the wedge on the thing and having to get a new one after 1600 shots or so. The arbor remained solid in the frame. This Pietta must have softer metal in the frame in order for the arbor to start wobbling, as I've only used pure lead roundballs in it and it's only been fired maybe 70 times. It probably couldn't get too much softer if soldering heat was applied, would it?