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Easy fix for short arbor

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m-g willy

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Seeing as a lot of cap and ball revolvers suffer from short arbors..I did some research on how to fix them..I seen where a set screw could be threaded into the arbor chamber? :hmm: ..housing :hmm: /HOLE UNDER THE BARREL :grin: !
Also seen where a metal spacer was fixed to the end of the arbor.
Well I think I got an easy quick fix that takes 0 skill and ends in a perfect fit.
Here it is.
This is what you need
Drill
5/32" drill bit
RELEASE AGENT
JB WELD or Brownells Bedding compound
PAPER TOWELS
Q-TIPS
.006 feeler gauge shim

CLEAN AND DEGREASE ARBOR HOUSING


#1.Remove rammer assembly
#2.Drill 5/32 hole completely through center of arbor housing.
#3.Put release agent on arbor ,and everywhere on outside of barrel that could possibly get over flow compound on it.
#4.Plug 5/32 hole from outside with Q-tip(Use just enough pressure to barely keep Q-tip from falling out)
#5.Mix JBweld,or brownnels bedding compound
#6.Use straw and suck JB WELD OR Bedding compound up straw(Don't be an idiot,,just get enough to fill 1/2" -1" of the bottom of the straw.What ever it takes to fill the gap :doh: )
#7.Hold straw end against something and squeeze out air pockets..
#8.Wipe outside of straw clean of any compound.
#9.Carefully put straw into arbor housing.
#10.Squeeze or blow compound into arbor housing.(KEEP BARREL POINTED DOWN :doh: )
#11.Take handgun frame with cylinder installed and insert arbor into place ,,(put .006 shim between barrel and cylinder.)Point pistol up!
#12.Push arbor completely into housing ,install wedge.,,,THE EXTRA COMPOUND WILL PUSH THE Q-TIP plug out and all extra compound will be forced out 5/32 hole.(Don't let it run all over gun)
Keep gun pointed up after cleaning off all compound forced out of hole.
I just did two revolvers (one Pietta and one Uberti,,One with JB weld and one with brownells bedding compound.Both guns came out perfect.
 

curator

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M-G willy:

Brilliant Fix for a common problem! I have struggled with making "buttons" to shim short arbors and your solution really makes perfect sense! Thanks for the insight!
 

MSW

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very clever ... thanks for the post! :hatsoff:
 

M. De Land

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I don't care to drill a weep hole in the end of the barrel arbor well.
All one has to do is accurately measure the depth and turn or file a slightly under size steel or brass filler plug that can be removed and trial fitted. Use a drop of loc-tite to keep it in place after final fitting.
 

Ray-Vigo

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M.D.: agree entirely.

I add thin washers until I get a match, then JB weld the washers together to make a single shim. Then loctite the shim in place in the arbor hole. I think each of my Ubertis has 2 washers as shims.

The addition of the shims cut down on fouling quite a bit and increased accuracy on both my Uberti Navy Colts.
 

m-g willy

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just wondering,,Has anyone used my method of fixing the short arbor problem with bedding compound,,And if you did,,do you still have the gun?..Because I bought a gun off an auction site that has had an action job and when I checked the arbor fit,,It was perfect..Then I seen it had the bedding compound fix I described...BTW-It is an 1860 army with fluted cylinder.
 

Siringo

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just wondering,,Has anyone used my method of fixing the short arbor problem with bedding compound,,And if you did,,do you still have the gun?..Because I bought a gun off an auction site that has had an action job and when I checked the arbor fit,,It was perfect..Then I seen it had the bedding compound fix I described...BTW-It is an 1860 army with fluted cylinder.
I used a nylon washer from the hardware store as a shim. Dropped it into the arbor bore. If necessary I sanded the thickness down a bit to get the proper fit.
 
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Zonie

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A easy way to find out if a Colt open top pistol has a "short arbor" is to place the gun at half cock, remove the barrel wedge and then rotate the cylinder until one of the areas that seperate the cylinders is under the loading ram. Use the ram to jack the barrel off of the arbor and then remove the cylinder from the arbor.

Replace the barrel onto the arbor with the lower lug turned out to the side so it doesn't try to engage the two frame pins and push it down onto the arbor until it stops.
Keeping pressure against the muzzle, rotate the barrel so the lower lug on the barrel moves over the front of the frame.

If it does move over the end of the frame without a visible gap, it is perfect.
If it moves over the end of the frame with a larger gap, the arbor is too long.
If it clunks into the side of the end of the frame, the arbor is too short and some sort of spacer needs to be added into the bottom of the arbor hole in the barrel.
The thickness of this spacer should be adjusted until the lower lug of the barrel just passes freely over the end of the frame without a large gap. I would say anything over .010 gap is too large. A .000 to .005 gap is just about perfect.
 

Stantheman86

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Excellent info , never even would have thought of this. Now I'll test my Dragoon and 51 Navy .
 

wb78963

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kind of killing a fly with a 105 howitzer. A #10 split washer (lock washer) dropped down the arbor hole will do the same thing a lot easier.
Or a brass washer JB'd to the end of the arbor and carefully filed to fit.
Sorry Pard but with your system system any thing goes wrong and you have turned the gun into a paper weight.
Very few things are forever but JB weld is one of them.
WB
 

hawkeye2

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Nothing lasts forever, a drill bit will remove the JB Weld.

I wouldn't drill a weep hole though. I would cut a small groove lengthwise on the arbor to let the excess epoxy out.
 
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Stantheman86

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Can you not just size the washer (shim) and just keep it loose in the arbor hole , being careful to replace it after cleaning?

I've used "endshake" shims in "unmentionable " revolvers, same concept, they just go into where they need to go and stay there, no glue , JB Weld, etc. They can be fished out with a dental pick.
 

hawkeye2

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Sure could Stan, just make 2 in case. It isn't hard to cure the problem but some methods are more sophisticated than others.
 

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