Getting a free Uberti ...needs work - Page 2

Delmar · March 14, 2010, 02:33 PM

Quote:

The arbor will not come out with this pin in place.

I took the gun to a fiend of mine who is a machinist and he got the pin out for me and threaded the hole for a set screw. I couldn't believe how much it tightened up the arbor. The wiggle is gone entirely!

Doc Hoy · March 14, 2010, 04:26 PM

What part of the frame did he drill for the set screw?

madcratebuilder · March 15, 2010, 10:30 AM

Doc, the pin is normally drilled half in the arbor, half in the frame. If you drill that pin out and then thread it you can use a setscrew when it goes back together. That well tighten up a loose arbor sometimes. Use a tap that has a good taper to it and don't use a bottom tap. You want the setscrew to be a interference fit as it bottoms out.

Doc Hoy · March 15, 2010, 10:47 AM

So you are saying that the set screw is installed in the same orientation as the original pin? Hole enlarged from the back of the pistol and then threaded which makes a lot of sense although it seems like a ticklish operation given the dissimilarities between steel (arbor) and brass (frame).

I pictured the set screw hole drilled perpendicular to the axis of the arbor.

If you drill down through the frame at a position which is underneath the hammer, the operation would remove a lot of metal from the frame and potentially weaken the frame at a point where there is not much metal in the first place. An alternate would be to drill in from the right side of the frame and catch the arbor that way. The problem here is that the set screw would be visible from the right side of the pistol. That would be unacceptible to some shooters. (I suppose it would be better than a loose arbor.) Drilling up from the underside of the frame would present much the same problem as drilling down. Not much metal under there. You can't drill from the left side of the pistol because of the interference created by the hand.

Delmar · March 15, 2010, 03:29 PM

The set screw simply replaces the pin, though it is a little larger diameter. The main advantage to a set screw, over a new pin, is that you don't need a machinist to take it out again.

Doc Hoy · March 15, 2010, 04:29 PM

Del,

I agree with you about three hundred percent. In fact I have always thought that the pin design is a little on the "Rube Goldberg" side. I don't know if originals came with the pin. But had I been a manufacturer concerned with keeping the arbor tight and axially alligned I think I would have drilled all the way through from top to bottom and through the arbor. I would have driven the pin into the frame. With the hole drilled all the way through the frame, the pin could be driven out easily if necessary. I do acknowledge that drilling the frame as I have described might weaken the frame.

I doubt that the manufacturers were much worried about arbors coming loose. I think their attitude was probably more like, once the pistol is out the door, the government will assme full responsibility for dealing with the failures.

Here is a question for you historians:

Isn't it true that most of the brass frame revolvers that were copied from the Colt open top design, were made in the South and were made during the war, not before the war? Did Colt manufacture any brass frame pistols in the 1851 or 1860 pattern?

Hawg · March 15, 2010, 04:42 PM

Quote:

Isn't it true that most of the brass frame revolvers that were copied from the Colt open top design, were made in the South and were made during the war, not before the war? Did Colt manufacture any brass frame pistols in the 1851 or 1860 pattern?

Yes it's true altho they weren't exactly brass but gunmetal which is a form of bronze with a high copper content. There is a Colt model 60 prototype in brass with a Mershon & Hollingsworth cocking system but it was never put into production.

Goatwhiskers · March 15, 2010, 07:49 PM

IF the cylinder arbor is threaded in place but loose, there is a thread restorer product available from Brownells. I only used it once on a screw and it seemed to work quite well--might be worth a try. A little easier than soldering. Goatwhiskers the Elder

March 14, 2010, 04:26 PM	#27
Doc Hoy Senior Member Join Date: October 24, 2008 Location: Naples, Fl Posts: 5,440	Del, What part of the frame did he drill for the set screw? __________________ Seek truth. Relax. Take a breath.

March 15, 2010, 10:47 AM	#29
Doc Hoy Senior Member Join Date: October 24, 2008 Location: Naples, Fl Posts: 5,440	MCB So you are saying that the set screw is installed in the same orientation as the original pin? Hole enlarged from the back of the pistol and then threaded which makes a lot of sense although it seems like a ticklish operation given the dissimilarities between steel (arbor) and brass (frame). I pictured the set screw hole drilled perpendicular to the axis of the arbor. If you drill down through the frame at a position which is underneath the hammer, the operation would remove a lot of metal from the frame and potentially weaken the frame at a point where there is not much metal in the first place. An alternate would be to drill in from the right side of the frame and catch the arbor that way. The problem here is that the set screw would be visible from the right side of the pistol. That would be unacceptible to some shooters. (I suppose it would be better than a loose arbor.) Drilling up from the underside of the frame would present much the same problem as drilling down. Not much metal under there. You can't drill from the left side of the pistol because of the interference created by the hand. __________________ Seek truth. Relax. Take a breath.

March 15, 2010, 04:29 PM	#31
Doc Hoy Senior Member Join Date: October 24, 2008 Location: Naples, Fl Posts: 5,440	Exactly right Del, I agree with you about three hundred percent. In fact I have always thought that the pin design is a little on the "Rube Goldberg" side. I don't know if originals came with the pin. But had I been a manufacturer concerned with keeping the arbor tight and axially alligned I think I would have drilled all the way through from top to bottom and through the arbor. I would have driven the pin into the frame. With the hole drilled all the way through the frame, the pin could be driven out easily if necessary. I do acknowledge that drilling the frame as I have described might weaken the frame. I doubt that the manufacturers were much worried about arbors coming loose. I think their attitude was probably more like, once the pistol is out the door, the government will assme full responsibility for dealing with the failures. Here is a question for you historians: Isn't it true that most of the brass frame revolvers that were copied from the Colt open top design, were made in the South and were made during the war, not before the war? Did Colt manufacture any brass frame pistols in the 1851 or 1860 pattern? __________________ Seek truth. Relax. Take a breath.

March 15, 2010, 10:30 AM	#28
madcratebuilder Senior Member Join Date: November 2, 2007 Location: Northern Orygun Posts: 4,923	Doc, the pin is normally drilled half in the arbor, half in the frame. If you drill that pin out and then thread it you can use a setscrew when it goes back together. That well tighten up a loose arbor sometimes. Use a tap that has a good taper to it and don't use a bottom tap. You want the setscrew to be a interference fit as it bottoms out.

March 15, 2010, 03:29 PM	#30
Delmar Senior Member Join Date: March 20, 2009 Location: Norhthern Indiana Posts: 307	The set screw simply replaces the pin, though it is a little larger diameter. The main advantage to a set screw, over a new pin, is that you don't need a machinist to take it out again.

March 15, 2010, 07:49 PM	#33
Goatwhiskers Senior Member Join Date: April 8, 2009 Location: Batchelor, La. Posts: 579	IF the cylinder arbor is threaded in place but loose, there is a thread restorer product available from Brownells. I only used it once on a screw and it seemed to work quite well--might be worth a try. A little easier than soldering. Goatwhiskers the Elder