Saturday, June 28, 2008

Covering Up The Front Sight Grooves

The Original (Diana) 45 has stamped grooves for the front sight, both on top and below (why?) at the front of the barrel.

I didn't want to remove them on the off chance I ever get a set of the original, Original, sights. But left as is they are ugly and not entirely comfortable to grasp while cocking.

So I drill.

And then drill deeper.

And bore to clear the grooves.

Boring picture of a bored tube.

Deburring the hole with a large countersink.

Turning down the OD.

And parted off the rod.

Flipped around it gets a rather large countersunk bore.

I thought I'd go for a minimalist tube look, but I didn't like it.

So I set the compound to about 3 degrees.

And turned a taper on it.

I took passes until the thinnest part of the tube was about .03"

Flipped and tapered in the front to about 60 degrees.

Making shims for the barrel.

Reaming to the diameter of the barrel.

Parting off two bushings.

Slitting the bushings.

Drilling for two #4-40 tapped holes. Using a ruler in between the bit and a round workpiece will show whether the drill bit is centered.

The shims on the barrel. These center the brake and protect the barrel from the setscrews.

The finished brake (really a barrel protector and cocking handle). It's a bit big, but sort of has to be due to the front sight grooves. So while I don't like it on aesthetic grounds, I have to admit it is comfortable to use when cocking the rifle.

If I was really cool I'd send it out for anodizing, but instead I'm hitting it with some semi-gloss black paint. It seems durable on the Diana 6 pistol frame, and will be more easily touched up.

Thursday, June 26, 2008

A Small Puzzle

So the stock screws in the forearm of the Original (Diana) 45 bear on the wood of the stock. I want to make some nice screw cups that will spread the load, as well as looking pretty.

The first problem is that the holes seem off center. I can of course make off center screw cups, but I have a feeling it would look odd. It's possible that the screws can be tweaked a bit to center, or I can enlarge and center the counter bored hole.

The other side. Now in order to figure out what would be the best option I have to remove the action from the stock. Will I have enough wood to remove a bit more? Is the action fully bedded, etc?

The problem is that there is a pin that goes through the action in the rear, through two washers in counterbored holes. Now it's entirely possible I can just drift the pin out and remove the action but it's also possible that drifting the pin out will cause springs, tiny parts and other items to fly out as soon as the action is removed from the I have to do a bit of research.

Tuesday, June 24, 2008

A Scope Stop for the Original (Diana) 45

So the scope mounts taken care of, I turned my attention to making a scope stop. With powerful spring piston guns a scope stop of some form is needed to prevent the scope mounts from moving under the recoil. It is worth noting that scope stops can be purchased for very little money, but having less than that in my budget I set to work...

Finding the edge of a .625" x .625" x .375" block of aluminum.

Milling the minor width of the dovetail slot.

Milling the dovetail with a 60 degree dovetail cutter.

Drilling the hole for the stop pin.

Reaming the hole for the stop pin. The reamer is held in a collet because of the lack of z-axis height on the Taig mill.

The work is flipped 90 degrees and the edges picked up again with an edge finder. Note the offset of the tip, this is what it looks like when it "kicks" out at the edge.

Drilling for the screw holes.

Sawing off one side of the dovetail. When I make another one I'll saw off both edges for better centering of the pin on the dovetail, but that's another story...

The two pieces.

Drilling the clamp part for #6 screw clearance.

Almost finished...but not.

I found that adding several washers maintained uniform clamping.

I then drilled a shallow hole in the scope rail, using the scope stop as a jig. I followed the drill up with an end mill to generate a flat bottom to the hole.

As you can see the hole is a little off center, as I said, it would have been better to make the stop adjustable for center.

Drilling the hole unfortunately wallowed out the carefully reamed hole in the stop, so I couldn't use a dowel pin as I planned.

So I made a pin out of some steel.

The completed stop. To prevent any movement, I used a small amount of loctite bearing retaining compound to lock the pin in.

The scope mounted again...I made small witness marks so I could keep track of whether the stop moves at all. As with all my mistakes, er, experiments, I'll report any movement after I fire a few hundred pellets through. Today's post on the Pyramyd Air blog shows what can happen if movement does occur in a stop like this, but I think the addition of the loctite will prevent that.