Building the Stevens Favorite

[Tom Griffin]

Re: Building the Stevens Favorite Rifle

Hi Ron,

The mild steel parts like the receiver and lever will be case hardened, everything else will be hardened through. That's the last step though, all of the parts will be checked for fit and function before anything is hardened.

Tom

 

[ScrapMetal]

Re: Building the Stevens Favorite Rifle

That's pretty much the answer I expected. I am not real knowledgeable on the finer points of tempering steel, when to, in which way, why, etc. so I appreciate learning more.

Thanks again,

-Ron

P.S. Nice, nice job so far. :thumbzup:

 

[Tom Griffin]

Re: Building the Stevens Favorite Rifle

that`s a slick little jig for bending the lever! this is good stuff! learning a lot here.

Thanks,

The type of work I do demands a lot of jigs like that, mostly made on the fly. Making a simple jig or fixture can shave hours off the time it takes to make a part and make it easier to machine at the same time.

Tom

 

[Tom Griffin]

Re: Building the Stevens Favorite Rifle

RE: Building The Steven's Favorite Tonight's task was the one thing I dreaded about making the lever. On the lever of the original Steven's, there was an internal pocket centered on the pivot to clear the end of the extractor which shared the same pivot point as the lever. It was a simple feature to include because the lever was cast and the pocket was just another part of the pattern. Since I am machining this lever, I had to either engineer the pocket out, which I couldn't figure a way to do, or machine it, which would be tough since it would be a blind cut inside the lever and the only access would be through a 9/32" pivot hole. The technique I decided to use was to make a single tooth cutter that I could insert through the 9/32" hole and use it as an end mill by rotating the lever on the rotary table. The catch was that since the shank diameter of the cutter would be 1/8" and the diameter of the pivot hole 7/32", I would only be able to move the cutter over about .04", not enough to machine the full diameter of the pocket in one setup. In other words it was going to take three different sized cutters to machine the pocket. The dastardly pocket can be seen in the section view of the drawing shown in the photo above.

The cutters were made of O1. I turned the 1/8" shank on the lathe, ground the form on the belt sander and grinder, hardened and then sharpened it. I almost completed the first cut, but the cutter shank broke at a stress point. I made another with larger radii and tempered the shank, leaving the cutting edge nearly full hard and the shank a bit springy. This one worked much better and I was able to finish what was left from the first pass plus a bit more. One more cutter will take the pocket to the full .406" diameter.

These simple paddle cutters are easy to make and should be considered when making a project. You can make them exactly the size needed and not have to settle for something close or spend a lot of cash to buy one. This one would work just as well as a boring bar instead of an end mill with some slightly different angles,. The cost was a 3" long piece of 3/8" drill rod and about 10 minutes worth of time.



The first cutter. This one was small enough that it fit straight through the 9/32" hole.



The second cutter, slightly larger diameter with the shank tempered blue for flexibility. This one had to be rocked through the hole which was a pain to set up, but it worked great.



The cutter in place, with the lever mounted on the rotary table, after taking three passes to cut the internal pocket.

Now that it is all finished I've found there is a better way to do the counter-bore. Jim Wisner pointed out that on the samples he uses to make reproduction parts, the counter-bore is cut through one side of the lever and then the outside part of the counter-bore filled with a bushing. Sounds like a good addition to REV B.



The next task will be to make the link and pins that connect the lever to the breech block. Then operating the lever will actually open and close the breech block.





The lever is finished, save some contour filing and polishing. I went ahead and made the link and the pins to attach it to the breech block and put it all together. Unfortunately I got ahead of myself and didn't take any pics. It's pretty encouraging to see everything operate as it's supposed to when the lever is cocked.

---

"Aviation is going to make such progress as cannot be imagined."

 

[Tom Griffin]

The lever is finished, save some contour filing and polishing. I went ahead and made the link and the pins to attach it to the breech block and put it all together. It's pretty encouraging to see everything operate as it's supposed to when the lever is cocked.

 

[Tom Griffin]

RE: Building The Steven's Favorite Not much time for the project tonight. Between a couple of chores and tip-off time time, I was only able to make the screw that attaches the end of the mainspring plunger to the receiver. Just a simple 8-32 thread, a .04" wide parted groove and a screwdriver slot in the head. This is the perfect application for a collet block.





The next task will be to make and install the pin for the clevis and to wind the mainspring if I have the right size music wire on hand.

Tonight I got started on the mainspring plunger. The Steven's uses a compression coil spring for a mainspring and it sits on a rod with a clevis on one end with a pin in it that pushes against the hammer. The other end rides in a bushing that hooks on the grooved screw that I made last night.



The first step was to square up a piece of O1, rough out the turned end and center drill each end so it could be turned between centers.



I rarely turn between centers so I didn't have the proper size dog on hand. The alternative was to drill an oversized center in the yoke end and use that to drive it. Thye driving center is just a piece of aluminum turned to a 60º point. It should work fine because the shaft is only 5/32" diameter and won't require much torque to drive.





The radii were cut with a corner rounding end mill. Next, the center of the clevis gets milled out. Not tonight though, it's been a long day. I'll be working at home in the morning and will need the mill so I guess I'll just have to finish it then.



Toolmaker's clamps aren't used often, but they worked well here to stabilize the .075" thick fingers on the clevis. Even so, with the long thin fingers and the long end mill, the potential for a spectacular wreck was high.







It's a nice day outside but I still managed to sneak into the shop for a bit and wind the mainspring. The method I use to make springs is to set the lathe up for the number of coils per inch, put a slotted wooden insert in the tool block to pinch the wire and provide tension and wrap it around a mandrel under power. The spring always ends up larger than the mandrel so figuring out the right size mandrel requires some experimentation. Once wound, it was clipped to length and the ends ground square on the belt sander.



This is the wooden tensioning block sawed out of a leftover piece of walnut from the stock. The amount of tension required depends on the diameter of the wire and sometimes takes some trial and error to get right.



Safety glasses are a must when working with any kind of wire, especially when winding springs. The mandrel I ended up using was a long aircraft drill about .015" under the finish diameter of the spring. Forcing springy wire to conform to the shape you want is a dicey proposition, so it's best to run the lathe at slow speed and stay well clear of the wire. The end of the mandrel is supported with a drill chuck snugged up and well oiled. The start of the spring has a 90º leg bent on it and pinched in the lathe chuck along with the mandrel.



The finished spring mounted on the mainspring plunger.



The spring force on the hammers feels a tad light, but it is only a .22. If it misfires I'll just re-wind the spring with .055" or .063" wire instead of the .047" I grabbed at the hobby shop. The hammer doesn't fall all the way yet because I still need to cut the notches and the extra stock is hitting something inside the receiver.

---

"Aviation is going to make such progress as cannot be imagined."

 

[Tom Griffin]

Tonight I got started on the mainspring plunger. The Steven's uses a compression coil spring for a mainspring and it sits on a rod with a clevis on one end with a pin in it that pushes against the hammer. The other end rides in a bushing that hooks on the grooved screw that I made last night.



The first step was to square up a piece of O1, rough out the turned end and center drill each end so it could be turned between centers.



I rarely turn between centers so I didn't have the proper size dog on hand. The alternative was to put an oversized center on the yoke end and use that to drive it. It should work fine because the shaft is only 5/32" diameter.






The radii were cut with a corner rounding end mill. Next, the center of the clevis gets milled out. Not tonight though, it's been a long day. I'll be working at home in the morning and will need the mill so I guess I'll just have to finish it then. :whistle:

The next task will be to make and install the pin for the clevis and to wind the mainspring if I have the right size music wire on hand.

 

[Tom Griffin]

Toolmaker's clamps aren't used often, but they worked well here to stabilize the .075" thick fingers on the clevis. Even so, with the long thin fingers and the long end mill, the potential for a spectacular wreck was high.







A spring and a pin will complete the mainspring assembly.

 

[Tom Griffin]

Today was hammer time. In between spring cleanup, I managed to get most of it completed. I chose to mount it on a sub plate as with the breech block and the receiver only the hammer only had one hole in it so I had tho add another in an area that would be cut out. I also decided to forego the screws and just use pins, relying on the clamps to hold everything down. I made a design change on the fly and added some extra material on the top for some cocking serrations and also some additional material on the half cock notch to make it more "safe" since the half cock position is the actual safety..









The rough shape is finished. The half cock and full cock notches still need to be cut and the top of the hammer serrated.

 

[mranum]

That is some awesome work!

Love this play by play too! Hope to see it till she's done.