Building the Stevens Favorite

[Tony Wells]

Tom, what's the slowest feed you have on that lathe? I would imagine you know it will require a slow feed, and there are recommendation tables available. I'm curious as to how this turns out. I need to build a dedicated drilling machine for a repeat job I do. It's not as long, and larger diameter, but I'll shamelessly use what you show to add to what I know about deep hole drilling.

 

[Tom Griffin]

Bill: Yeah, that revelation ruined a perfectly good nap. Choking up on it makes everything simpler.

Tony: The Hardinge has a variable electric feed so getting it slow enough won't be a problem. Go ahead and use anything you see here, someone else has likely thought of it before me anyway.

Tom

 

[Tom Griffin]

I caught the plague last week so productivity took a bit of a dive. Feeling better this weekend, I managed to put a few hours in on the drilling rig for the Steven's. This is the guide plate used to start the gun drill on center in the end of the barrel. It consists of a plate attached to the ways of the lathe with a drill guide bushing mounted in a hub with a bit of adjustment built in to allow the bushing to be precisely centered on the spindle.

The next step is to make a chip box that attaches to the plate to catch the chip laden cutting oil as it sprays out the end of the barrel during the drilling procedure. It'll just be a simple sheet metal box with some sort of rubber seal on the holes where the drill passes through, and a drain out the bottom.

Tom

 

[Siskiyous]

These are the best detailed photos and descriptions of setting up to do a deep bore that I have ever ran across. Thank you for taking the time to document it all so well.

 

[Tom Griffin]

Thanks.

There are lots of other projects going on at the moment but I'll be getting back to this one shortly. Next in line will be a high pressure pump for the cutting oil and a bracket so I can drive it with my mill. Also the chip box to enclose the guide bushing and catch the oil so I don't end up painting my shop with it.

Tom

 

[Tom Griffin]

I had planned to work on the gun drilling set-up over the Christmas break, but the hydraulic pump that I ordered didn't show up on time (it arrived today). Instead, I made a few engineering changes to the tang sight design and finished it up, made the detail drawings and started building it.

The sight is my own design, based on the best features of various sights I found on the internet. It is a flip up design with detents in the up and down position, has a windage adjustment via a thumbwheel, a sliding center to set the elevation and a turn of the peep sight locks everything in position.



The first part in the cue was the locknut/windage adjustment. It is a simple block with a notch for the windage thumbwheel and a 1/4-36 tapped hole for the peep sight to screw into. I needed to make it first so I could use it as a thread gauge for the matching 1/4-36 thread on the peep sight.

Next in line was the peep sight itself. The the back side of the hood and the threaded shaft was turned first, then it was parted off and held in a collet to turn the cup shaped bore typical to these sights and knurl the outside.





Next comes the sliding mechanism, windage thumbwheel and the frame to hold it all.

Tom

 

[Tom Griffin]

A couple more parts for the sight, the center section that holds the peep sight and slides up and down in the frame. The two parts were just simple rectangular blocks with a couple of slots and a pocket in one. The only thing difficult about making them was the small size as shown in the pic.



Cutting the 1/32" radii with a form tool in a fly cutter.




The frame to hold these first parts is well underway and will be posted tomorrow. It's a bit more complex and will include some rotary table work, so I'll include more pics of the build.

Tom

 

[Tom Griffin]

The frame for the sight turned out to be fairly involved so I took a few more pics of the process:



It's in there.




Squared up and sized for width, with extra stock on the ends and the thickness for the rotary table work.




The 1" radius belt sanded on one end.




Roughing out the blade thickness.




Blade finished to size.




the 1/8" pivot hole reamed to size and ready to be set up on the rotary table.




This is the method I use to center the rotary table on the spindle. I made a snug fitting plug for the center of the table with a snug fitting hole in the center for a 3/8" dowel. With the dowel chucked in a collet, it is inserted in the plug to center the table, the DRO is zeroed out and the table bolted down.




The same process is used to center the part. With the rotary table centered on the spindle, a 1/8" pin is held in a collet and the part placed on it, then the angle plate is clamped to the part and then bolted to the table. The part is then indicated parallel to the X axis and the rotary table zeroed out.




The part was then counterbored with the end mill and the profile milled. Then the part was flipped and the other side was counterbored.




The holes for the detents, a spring and two balls, being drilled.




Assembled and partially polished.




All that is left is the thumb nut for setting the windage, the #1-72 threaded rod that it rides on and the base.

 

[Tom Griffin]

I finished machining the base tonight. There is a fair amount of shape to it, such as radiused corners and surfaces typical to firearms, and that will be done by hand, but all the machining is complete.



This is the radius on the underside of the base that matches the radius on the tang of the receiver (tang sight, get it?). It was accomplished by mounting a fly cutter in the boring head to achieve the 1.500" radius.




Here the basic shape is roughed out and the mounting holes added. The top surface will ultimately have a convex curve to it that will be machined with a 3/4" ball end mill on the rotary table.




Here, the base is mounted to a fixture on the rotary table to generate the convex top surface using the 3/4" ball end mill. The fixture is just a piece of 3 1/4" aluminum round with a slot the width of the base and a couple of tapped holes. I figured the slot was good insurance to take some of the load off the 4-40 mounting screws since some of the head on them would be milled off.




The base was then mounted to an angle plate on the rotary table to machine the .200" radius on the center section. Both the table and the part were located using gauge pins in the spindle just as with the frame.




Here it is as machined. To finish it up, all surfaces will be polished and many of the corners rounded. Since everything is O1, it should polish up nicely. Unfortunately, on a part like this, that will all need to be done by hand. It's the extra work that goes into shaping parts like this that gives a firearm it's character.




Almost done. I still need to make the windage thumbnut and assemble the detent mechanism. I see the parts showed up today, some 3/32" compression springs and balls, and the 1-72 threaded rod for the windage adjustment. That will be tomorrow evenings project.

 

[jumps4]

i'm not a gun making fan but i always look forward to your next pics
your skills at manual machining are impressive and i learn a new tip or trick from every setup
thanks for sharing
steve