restoring a cam on an 1860 hammer

[M. De Land]

A bit more on the wedge construction may be of interest to you. The spring on the factory wedge is not only a keep from the stand point of loosing it while cleaning but the tension it self against the top of the wedge slot while in place tends to discourage it loosing and creeping outward.
This is the part I said in the previous post that I had found unnecessary as the ones I make have not, to this point any way, tended to loosen and creep out on there own.

This is also why I maintain that the wedge thickness is as important as its width and taper. One mans opinion .

 

[M. De Land]

Got back to work on the 60 this AM. Turned a new cam of O-1 in the lathe , filed new cam angle, fit to old, drilled out cam hole, hardened and re-set. The cam protrusion is about .070 and the cam angle taper is from top to bottom. The cam angle is clocked a couple of degree toward the axial hole from what I can see using my own 60 hammer for comparison. The work edge of the new cam was broke with a fine diamond file to remove any sharpness so as not to carve up the bolt finger. I left it full hard not drawing the temper on this particular part as it won't be doing any flexing or have sharp impact to endure.
Next job is barrel set up in lathe to trim lower lug about .023 and end fit arbor.
I'll post some pictures of this stuff as I go for those who may be interested .
I think I will probably need to make a new wedge as well but will see as the build progresses.

Here are a couple of shots to show the excessive cylinder and lower lug gaps when wedge is fully inserted. The lower lug should be making full and even contact with the wedge fully inserted and the cylinder barrel gap should be even around the clock at firing which means it will be a bit tighter at the top at rest. Click on photo to enlarge.

 

[M. De Land]

There is one small point I would like to make in a term cross use with percussion revolvers as opposed to modern. End shake is a term used in modern cartridge revolvers which effects barrel cylinder gap but is actually talking about the protrusion sticking out of the cylinder front at the base pin and its fit to the frame. This gap generally is set to no more than .001 for good clearance but not enough to let the cylinder move for and aft much. The barrel /cylinder gap is another tolerance , related to but completely separate from end shake.
The tolerance for end shake is much smaller than what is considered correct for barrel/cylinder gap.

 

[45D]

The protrusion in front of the cyl is typically called a bushing or gas ring. This bushing shields the base pin from fouling and keeps the cylinder rotating freely. It is also what keeps the face of the cyl from contacting the barrel and defines the barrel cylinder "gap" (at minimum, a "defined" opening). Endshake is the clearance between the bushing and frame (stopping surface) . . . meaning how much fore and aft movement a cylinder has. Cylinders with a removable bushing ( such as a Colt SAA / copy) can easily be shimed for a "0" or imperceptible Endshake. This is an important "wear" factor for revolvers as the more Endshake a revolver has, the greater the damage done shot to shot.

Since our "favorite" revolvers (open top percussion Colt style revolvers) don't have a bushing ( thus a defined opening) all they have IS Endshake. Since the cyl face contacts the barrel with each action cycle, you could say it's "self cleaning"!! Lol. Therefore, my reason for a "tight" clearance of .0025" - .003" for cap guns and .0015" - .002" for unmentionables is to protect the revolver from damage . . .
It protects the barrel, cylinder, wedge, the barrel and arbor wedge slots. The more movement the cylinder has, the more and faster damage will result.

Mike

 

[M. De Land]

The protrusion in front of the cyl is typically called a bushing or gas ring. This bushing shields the base pin from fouling and keeps the cylinder rotating freely. It is also what keeps the face of the cyl from contacting the barrel and defines the barrel cylinder "gap" (at minimum, a "defined" opening). Endshake is the clearance between the bushing and frame (stopping surface) . . . meaning how much fore and aft movement a cylinder has. Cylinders with a removable bushing ( such as a Colt SAA / copy) can easily be shimed for a "0" or imperceptible Endshake. This is an important "wear" factor for revolvers as the more Endshake a revolver has, the greater the damage done shot to shot.

Since our "favorite" revolvers (open top percussion Colt style revolvers) don't have a bushing ( thus a defined opening) all they have IS Endshake. Since the cyl face contacts the barrel with each action cycle, you could say it's "self cleaning"!! Lol. Therefore, my reason for a "tight" clearance of .0025" - .003" for cap guns and .0015" - .002" for unmentionables is to protect the revolver from damage . . .
It protects the barrel, cylinder, wedge, the barrel and arbor wedge slots. The more movement the cylinder has, the more and faster damage will result.

Mike

Yes, agreed, I thought about pointing that out but felt is was obvious, The term is specific to cartridge revolvers.

 

[45D]

Yes, agreed, I thought about pointing that out but felt is was obvious, The term is specific to cartridge revolvers.

Well, I used to call it "barrel/ cylinder clearance" but folks would confuse it with "gap". Endshake is "specifically" the fore and aft movement of the cylinder so it's a more appropriate term "modern" or not. Main thing is that we all understand these revolvers don't have a gap, they have a "clearance " or "endshake ".

Mike

 

[M. De Land]

Here are a couple of shots to show the excessive cylinder and lower lug gaps when wedge is fully inserted. The lower lug should be making full and even contact with the wedge fully inserted and the cylinder barrel gap should be even around the clock at firing which means it will be a bit tighter at the top at rest. Click on photo to enlarge.

I took a new hand file tonight and diamond filed three safe sides to make a hand broach to lengthen the wedge slot forward .020 the barrel is being set back. It is a very close slip fit to the factory wedge slot.
Once that was accomplished I turned two brass bushing centers and fit them to the bore of the barrel for and aft so I could turn the lug height in the lathe between centers.
The cuts were made using no more than .005 depth so as not to distort the lug alignment. The cross feed was by hand slow and methodical.
Took out .010 , removed and try fit to the frame. Good close lug fit with cylinder in place but need a bit more so back into the lathe and took another .004. Now it looks like the arbor is bottomed out and will need fitting. Good job for tomorrow, it's getting late !
I will need to make a new wedge as I expected.
I checked the bore and true to form there is about a .0015 to .002 constriction 6 1/8 inches in from the muzzle. The bore at the breech to the constriction measures .437+ and the muzzle down to the constriction is .436+. A .434 plug gauge will pass the constriction. So it looks like a lapp job is on the horizon as well unless it happens to be a gain twist then lead lapping is out.
A good sharp bit in the tool post and slow feed makes a real clean and level cut !

 

[M. De Land]

I took a new hand file tonight and diamond filed three safe sides to make a hand broach to lengthen the wedge slot forward .020 the barrel is being set back. It is a very close slip fit to the factory wedge slot.
Once that was accomplished I turned two brass bushing centers and fit them to the bore of the barrel for and aft so I could turn the lug height in the lathe between centers.
The cuts were made using no more than .005 depth so as not to distort the lug alignment. The cross feed was by hand slow and methodical.
Took out .010 , removed and try fit to the frame. Good close lug fit with cylinder in place but need a bit more so back into the lathe and took another .004. Now it looks like the arbor is bottomed out and will need fitting. Good job for tomorrow, it's getting late !
I will need to make a new wedge as I expected.
I checked the bore and true to form there is about a .0015 to .002 constriction 6 1/8 inches in from the muzzle. The bore at the breech to the constriction measures .437+ and the muzzle down to the constriction is .436+. A .434 plug gauge will pass the constriction. So it looks like a lapp job is on the horizon as well unless it happens to be a gain twist then lead lapping is out.
A good sharp bit in the tool post and slow feed makes a real clean and level cut !

It looks like the factory cut forcing cone needs a touch up as well, looking at the broach picture this AM. I already did the crown but for some reason got side tracked and didn't see this. That bugger will hook/shave lead the way that it is now, I believe.
I also need to check bore/chamber alignment and chamber mouth diameters and round which are probably out as well. Might as well give her the full treatment while at it. It is a good friends gun and an interesting project for me . Maybe we can turn a sows ear into a silk purse after all !

 

[M. De Land]

I took a new hand file tonight and diamond filed three safe sides to make a hand broach to lengthen the wedge slot forward .020 the barrel is being set back. It is a very close slip fit to the factory wedge slot.
Once that was accomplished I turned two brass bushing centers and fit them to the bore of the barrel for and aft so I could turn the lug height in the lathe between centers.
The cuts were made using no more than .005 depth so as not to distort the lug alignment. The cross feed was by hand slow and methodical.
Took out .010 , removed and try fit to the frame. Good close lug fit with cylinder in place but need a bit more so back into the lathe and took another .004. Now it looks like the arbor is bottomed out and will need fitting. Good job for tomorrow, it's getting late !
I will need to make a new wedge as I expected.
I checked the bore and true to form there is about a .0015 to .002 constriction 6 1/8 inches in from the muzzle. The bore at the breech to the constriction measures .437+ and the muzzle down to the constriction is .436+. A .434 plug gauge will pass the constriction. So it looks like a lapp job is on the horizon as well unless it happens to be a gain twist then lead lapping is out.
A good sharp bit in the tool post and slow feed makes a real clean and level cut !

I milled out the wedge tonight to rough dimension and will hopefully finish mill, part, hand fit then harden this week as work allows.I took a few more shots of the process for folks to look at if they like .
1. Ball milling the keep slot.
2. End milling the body thickness. I need to finish up some where close to .143 and am at .148. in the last picture. I need to leave it about .002 thicker so as to draw file out the cutter scratches to finish dimension.
3. The protractor says the wedge angle is 5 degrees so I will part it from the stock length on the mill with the mill vice protractor set at 5 degrees.
I wound up using the vertical mill as it was and easier set up .
I did not work out the tangent of angle width increase but did increase the width by about .020 along the angled side figuring that would give me enough margin to file fit before hardening. The fit has to come from the front side so as not to change the center of the keep groove with the keep screw in the barrel.
I'll take some shim stock and shim up the old wedge in the barrel slots to get the arbor fit correctly than transfer that over to the new wedge width.

 

[M. De Land]

I milled out the wedge tonight to rough dimension and will hopefully finish mill, part, hand fit then harden this week as work allows.I took a few more shots of the process for folks to look at if they like .
1. Ball milling the keep slot.
2. End milling the body thickness. I need to finish up some where close to .143 and am at .148. in the last picture. I need to leave it about .002 thicker so as to draw file out the cutter scratches to finish dimension.
3. The protractor says the wedge angle is 5 degrees so I will part it from the stock length on the mill with the mill vice protractor set at 5 degrees.
I wound up using the vertical mill as it was and easier set up .
I did not work out the tangent of angle width increase but did increase the width by about .020 along the angled side figuring that would give me enough margin to file fit before hardening. The fit has to come from the front side so as not to change the center of the keep groove with the keep screw in the barrel.
I'll take some shim stock and shim up the old wedge in the barrel slots to get the arbor fit correctly than transfer that over to the new wedge width.
View attachment 160485

Well the barrel is set back about .022 and with the wedge shims and old wedge in place and the lug fit up tight she measures .0035 with the feeler gauge in the barrel gap. I still had to make a .017 shim to make contact on the end of the arbor which I sure didn't think would happen with all the set back.
You can see the shim stock sticking out the side behind the old wedge.
Other side view.
A .004 feeler gauge is to tight and .003 is just touching both sides with a bit to much slack so I call it .0035.

 

[M. De Land]

The wedge is parted off the bar stock and am into final fitting before hardening. Been awhile since I made a wedge and I had forgotten how much time it takes to make, fit and harden a new one. It's still got a good 3/16s of an inch or so deeper to go before it will be adjusted the way I want. I'll put a mild radius on both ends before hardening but that will be the last thing to file.
Note the tight fit of the wedge thickness to the slot height with all corners deeply radius-ed. I believe this is what keeps them in tight and from creeping out as one fires .
Does anyone recognize the markings on the side of the barrel as to the maker ? All I could find was Made in Belgium .

 

[Bad Karma]

Centaure?

 

[Bad Karma]

Just notice that roll markin on the barrel, definitely Centaure.

 

[45D]

Well, at least we know why the "quality" and clearances are what they are!! I think the Centaures are about as rampant with "quality" as ASM was !!

Mike

 

[Bad Karma]

Some were pretty good. Some others, not so much.

 

[M. De Land]

+

Some were pretty good. Some others, not so much.

THANKS for the help guys. I'm not familiar with this make and it appears I have a "not so much "example although the barrel and arbor steel feel right when file or lapping them. The cam was soft and it makes me wonder about the trigger. The old wedge appears to be plenty hard and not deformed upon closer examination so I'll keep it as a spare part.
If the trigger needs remade or re- hardened I'll probably make a new spring for it as well with the Luftkin tape, flat/ coil spring I like to use for them . It provides ideal spring tension and are practically indestructible.
One caution with the use of this thin spring stock for trigger/bolt springs is to shorten the keep screw or use a washer as it may protrude to far through the bottom of the frame and scrub the cylinder. I found this out the hard way !
Oh, one more thing I noticed last night when fitting the wedge is the cylinder face will need truing as it had tight spots against the feeler gauge in one or two places. I'm guessing where it is stamped and pucker-ed up.

 

[M. De Land]

Well, at least we know why the "quality" and clearances are what they are!! I think the Centaures are about as rampant with "quality" as ASM was !!

Mike

I had occasion to work on several ASM's cartridge, open frame conversion guns and totally agree with the poor fit quality! The price my friend paid for them was also way out of balance for the quality but I didn't have the heart to tell him so .

 

[M. De Land]

I had occasion to work on several ASM's cartridge, open frame conversion guns and totally agree with the poor fit quality! The price my friend paid for them was also way out of balance for the quality but I didn't have the heart to tell him so .

And the trials just keep coming with this gun!
A couple of strokes on the diamond file plate reveals how out of true the face of this cylinder is. I shudder to think what I'm going to find when I check diameter and roundness of each chamber,. I guess I need to encircle the OD of the cylinder with shim stock so as not to mar it in the three jaw lathe chuck and then with the tail stock rotary diamond file the face square and even. That means I'll need to set it back more and take a couple more thousands off the lug and reduce the arbor shim. Glad I still have a lot of wedge depth angle left to fit. Two steps ahead and one back it seems at times.
Notice the "Gorilla" #1 stamped into the edge of the chamber mouth ! Must have been third shift Friday night or something !
The wedge is turning out well so far but one can always screw up a job with a brain fart at the right time! Been there done that............... more than once !
Remember to click on the frames to enlarge so one can see the details .

 

[M. De Land]

And the trials just keep coming with this gun!
A couple of strokes on the diamond file plate reveals how out of true the face of this cylinder is. I shudder to think what I'm going to find when I check diameter and roundness of each chamber,. I guess I need to encircle the OD of the cylinder with shim stock so as not to mar it in the three jaw lathe chuck and then with the tail stock rotary diamond file the face square and even. That means I'll need to set it back more and take a couple more thousands off the lug and reduce the arbor shim. Glad I still have a lot of wedge depth angle left to fit. Two steps ahead and one back it seems at times.
Notice the "Gorilla" #1 stamped into the edge of the chamber mouth ! Must have been third shift Friday night or something !
The wedge is turning out well so far but one can always screw up a job with a brain fart at the right time! Been there done that............... more than once !
Remember to click on the frames to enlarge so one can see the details .

I went ahead and trued up the cylinder face this evening in the lathe and took some shots of how I do this. The OD of the cylinder would have been established at the factory with a mandrel through the arbor hole which pretty much guarantees concentric with OD . This allows a set up in a three or four jaw chuck and a tail stock dead center in the arbor hole as can be seen in the set up shot. Once the cylinder is secure the dead center is removed from the tail stock and the square front of the tool barrel is used as the square back for the diamond plate file. The tail stock is fed in by hand pressure instead of using the turret screw, the lathe ways keeping every thing lined up and square. When the file stops wobbling against the cylinder face the job of squaring and truing is finished'. I didn't want to take any more material out than what it would take to get the face flat and square so left a few factory tool marks. I think I removed about .003 and will find out tormorrow when I put it all back together and check with a feeler gauge.

 

[hrt4me]

your work on this Centaur would pique interest on the FROCs website