Uberti short arbor question

[SDSmlf]

Come on guys!!! You need a protractor, a divider, slide rule, machinest's ruler, a micrometer and a feeler gage with .0015", .002", .0025" and .003" leaves.

Throw all of them in a drawer except for the feeler gage.
- Cut the head of a #14 stainless steel Pan Head sheet metal screw. There, that's all the "spacer" you need.
- Drop it round side down into the arbor hole. The "round" part of the head will self level in the drill point of the hole. Install the arbor and check for contact at the barrel lug/ frame. There will be space there so sand the flat side of the spacer to reduce thickness and check again.

-When contact is made, start driving the wedge in ( as soon as you can) while you check the endshake. Keep reducing the spacer until you get to the endshake you want. That's all there is to it and all the "measuring" you need to do. Very simple.

Tips-
To speed things up, I use a bench belt sander and a drill motor with a Philips head bit. I stop thinning the spacer when endshake gets to about. 004" and start reducing the end of the arbor for a more controlled "zeroing in" on my .0025" - .003" tolerance.
Doing it this way increases the total wedge slot slightly but I regain it with my set screw (adjustable wedge bearing) in the arbor for the wedge. Been doing it this way for 10 years!

Mike

Might have missed it, but what keeps the head of a #14 stainless steel Pan Head sheet metal screw in place next time one disassembles the gun? I hate it when shims fall out of blind holes and I don’t realize it.

 

[45D]

I use 2 part JB Weld (5 minute )
Make sure to degrease well.

My method:
I add 2 anchoring holes just as an insurance. These are drilled right where the shoulder of the arbor hole ends and the drill tip ( cone shaped end) begins. You can access through the wedge slot , one on each side. All you need is to start a hole, not very deep at all.
If you put some grease on the end of the arbor, you can stick the spacer on (remember, flat side to the grease!!!) and then add a small "blob" of JB ( you don't need a LOT!). Now you can install the spacer by installing the arbor (cylinder in place!!) and driving in the wedge. Let it set for 10 minutes and remove the arbor ( might need to use the rammer if you were sloppy!!) and clean up grease and any JB flakes. Next time you take the revolver down, you should see a contact ring (witness ring/mark) on the spacer.

Now you have a solid bottom for the arbor to butt up against for a solid connection along with a transmission line for vibration/harmonics to flow.

Mike

 

[Jim in Wisconsin]

That's the same way ol Sam Colt did it!

 

[SPQR70AD]

Come on guys!!! You need a protractor, a divider, slide rule, machinest's ruler, a micrometer and a feeler gage with .0015", .002", .0025" and .003" leaves.

Throw all of them in a drawer except for the feeler gage.
- Cut the head of a #14 stainless steel Pan Head sheet metal screw. There, that's all the "spacer" you need.
- Drop it round side down into the arbor hole. The "round" part of the head will self level in the drill point of the hole. Install the arbor and check for contact at the barrel lug/ frame. There will be space there so sand the flat side of the spacer to reduce thickness and check again.

-When contact is made, start driving the wedge in ( as soon as you can) while you check the endshake. Keep reducing the spacer until you get to the endshake you want. That's all there is to it and all the "measuring" you need to do. Very simple.

Tips-
To speed things up, I use a bench belt sander and a drill motor with a Philips head bit. I stop thinning the spacer when endshake gets to about. 004" and start reducing the end of the arbor for a more controlled "zeroing in" on my .0025" - .003" tolerance.
Doing it this way increases the total wedge slot slightly but I regain it with my set screw (adjustable wedge bearing) in the arbor for the wedge. Been doing it this way for 10 years!

Oh, for belt pistols ( Army's/ Navy's) use a #12 pan head screw.

Mike

Edit- Dang !!! Didn't think about that Hawkeye!!!

lol good post some guys just like making simple fixes like doing brain surgery

 

[M. De Land]

That's the same way ol Sam Colt did it!

With a #14 pan head screw ? If he did it at all it would be end fit one piece, trial an error, using a measuring gauge of one kind or another to begin with . Probably the proud arbor itself file trimmed to fit.

 

[45D]

With a #14 pan head screw ? If he did it at all it would be end fit one piece, trial an error, using a measuring gauge of one kind or another to begin with . Probably the proud arbor itself file trimmed to fit.

Lol!! No, Sam didn't do it that way. I believe Jim was referring to the solid contact as the originals have.

Mike

 

[Nobade]

OK, this is all very funny and I realize how you do something depends on what tools you have available. I worked in a custom rifle shop, and all the measuring tools are second nature. It's trivial to measure two points and whip out the exactly right spacer on the lathe compared to sticking a screw head in a hole and repeatedly grinding on it to get what I want. But obviously if I didn't have those tools I wouldn't do it that way. There are many ways to get to the same point.

 

[M. De Land]

OK, this is all very funny and I realize how you do something depends on what tools you have available. I worked in a custom rifle shop, and all the measuring tools are second nature. It's trivial to measure two points and whip out the exactly right spacer on the lathe compared to sticking a screw head in a hole and repeatedly grinding on it to get what I want. But obviously if I didn't have those tools I wouldn't do it that way. There are many ways to get to the same point.

Amen!

 

[45D]

OK, this is all very funny and I realize how you do something depends on what tools you have available. I worked in a custom rifle shop, and all the measuring tools are second nature. It's trivial to measure two points and whip out the exactly right spacer on the lathe compared to sticking a screw head in a hole and repeatedly grinding on it to get what I want. But obviously if I didn't have those tools I wouldn't do it that way. There are many ways to get to the same point.

That's all true. The problem with measuring an "exact amount" will become apparent when the wedge is driven in and tension is applied to the whole ( total). Your initial compression of materials, target endshake . . . will all change. That's why "thumb pressure " isn't enough to truly set the wedge. You can press all you want but when you drive it in ,the numbers will change. You have to hand fit ( just like all the other action parts) to get "it" right. Otherwise, you'll have to just accept "within tolerance".

Mike

BTW, "sticking" the finished spacer on the end of the arbor is for final installation ( just for ease of install) (you've got to read every word of the "redneck method" or you may miss something!)

 

[45D]

The method used above allows my Uberti 1860 to fire 21,000 + PSI ammo without any damage to the revolver. The endshake is .002" .

Mike

 

[M. De Land]

The method used above allows my Uberti 1860 to fire 21,000 + PSI ammo without any damage to the revolver. The endshake is .002" .

Mike

What kind of groups are you able to get at 25 yards with your set up Mike? Have you reamed the chamber mouths and checked/lapped the barrel for tight spots which may or may not improve things ?
I worked over a trigger on a Ruger SBH many years ago for a friend that was horribly out of chamber/bore alignment and I expected it to both spit lead and be inaccurate , Test group firing over sand bags proved me wrong on both accounts! Go figure, it should not have been accurate at any range but it was at the 25 yards tested anyway !

 

[45D]

What kind of groups are you able to get at 25 yards with your set up Mike? Have you reamed the chamber mouths and checked/lapped the barrel for tight spots which may or may not improve things ?
I worked over a trigger on a Ruger SBH many years ago for a friend that was horribly out of chamber/bore alignment and I expected it to both spit lead and be inaccurate , Test group firing over sand bags proved me wrong on both accounts! Go figure, it should not have been accurate at any range but it was at the 25 yards tested anyway !

Haven't done any shooting at 25 yds. This is a brand new cyl. (1 of 5 at the time ever in the caliber) in a brand new '60, so the range shooting was more for function than anything else.
I will say the second range trip with it I took some "platform testing" rounds with me ( to confirm the ability of the o.t. design) and there were no signs of any stretching, battering, frame failure, wedge upsetting, wedge slot (arbor or barrel). Those rounds, I noticed, were quite accurate ( all function shots fired freehand at 10 yds).
So, I will update as range times happen. This "hot rod" '60 has become a favorite of mine not only because it was first in this round, but this setup allows a true "testbed" to see what the platform is capable of.

Mike