Saturday, August 15, 2009

Match Grips for a Crosman 22XX Part 4 Final

With the shelf attachment complete, I began shaping the exterior of said palm shelf.

I wanted to make the shelf look like it belonged to the rest of the grip. While it would have been easy to leave it blocky and functional. I wanted an integrated and aesthetic look, too.

I thinned the underside of the front with a curve.

Decided to put a sloped curve on the rear of the shelf and continue that curve through the left-side grip. It's about 85% finished here.

Continuing that curve up the left grip. Note that the grips are bolted to a spare grip frame and being worked as one piece.

Still finding pressure points on the grip as well. A pencil scribble on the top of the right grip marks the area for some sanding attention. It's never too late to fine tune the grip to hand fit.

Remember that 1/4" thick spacer?

It's glued to the inside of the right grip panel. I mentioned previously that I'd deepened the slots for the palm shelf adjustment bolts. The relief grooves now go just high enough above the spacer that I can drop the 6-32 square nuts in from the top. This allows for a damaged square nut fastener to be replaced effortlessly.

Spacer positioned with both grip panels bolted in place then clamped.

While the glue dried, I got out a surface plate and finish sanded the shelf.

Here's a good shot of the curved front.

Done.

Spacer stands proud of the grip, ready for fitting.

The spacer was sanded down in just a couple minutes. You now have to look hard to find the transition line. Only the slight grain direction difference gives it away.

Finish sanded both grips. I was prepared to stipple the gripping areas, but was talked out of it--at least for now. Areas to be stippled really don't need to be sanded past about 120 grit. In this case, the entire grip was sanded to 300 something grit.

A coat of filler...

After they've dried.

Then the grip is rubbed down with 0000 steel wool and some of this stuff until there's no gloss left from the filler.

Just a bit of boiled linseed oil and some polishing with a rag.

Some "glamour shots":









Overall, I'm quite pleased with the way the grips turned out. Most importantly, they fit my hand far better than I could have hoped. While a Crosman 22XX isn't a 10-meter target pistol by any stretch, with a simple trigger job and some practice, it's a fantastic shooter for such a minimal cash outlay.

Thursday, August 13, 2009

Match Grips for a Crosman 22XX Part 3

And the shaping continues.

A small sanding drum from a Dremel tool grinds a notch for the safety.

Test fit looks good.

Bolted the grips to the frame and sanded the bottoms flat as one piece.

Then set the grip frame on top of the same walnut board the grips came from... Traced around the base of the right-side grip and sketched out a palm shelf. Uh, there's a knot hole there.

Intentionally cut the palm shelf slightly oversize to allow for shaping.

A piece of scrap walnut was planed down to 1/4" thickness...

...to make a spacer for the gap at the bottom of the grip frame.

Traced.

Cut just oversize.



Sanded to fit against the bottom of the frame. Only the front, bottom and back edges will be visible upon completion. Those sides will get sanded flush a bit later.

Had to do some minor fitting of the palm shelf so it would slide up and down the grip. The clearance against the bottom of the grip frame was giving me some headaches.

I thought the knot hole added some nice grain swirls and added visual appeal (that's why I used that section of the board).

More of the endless test fitting. Still need to attach the palm shelf to the right-side grip panel.

Drilled two holes in the shelf. A single, center bolt would work, but I've found that two-bolt shelves are more secure and don't cant and shift under hand pressure.

Drilled the second hole then set the depth stop and counterbored with a forstner bit for the allen heads. Use 6-32 fasteners just to be consistent. (Crosman 22XX grips use 6-32's)

Set the palm shelf on the grip, inserted a transfer punch through one bolt hole. Slid the shelf up and down the grip leaving a scribed line. Repeated in the other hole. These mark the centers of the adjustment slots needed.

Mounted the grip in the Taig vertical slide. Essentially, this attachment turns the lathe into a horizontal mill. A 1/8" center cutting end mill was mounted into the headstock and the grooves were cut like butter.

Reversed the set-up and used a larger end mill to cut shallow relief grooves for the nuts.

Nothing fancy. A couple 6-32 square nuts in the recesses will allow the palm rest to slide up and down for adjustment. Not shown: I ended up re-cutting the grooves and recesses to allow for a bit more additional upward adjustment.

A bolt-on test fit. Progress!

Still more to come.

Tuesday, August 11, 2009

Disassembling an IZH Baikal 513M, Part 3

On I go...

Rear bushing and washer...

Spring guide and washers.

One steel washer and one polymer washer, presumably to tame the vibration. It's looking like the only lube IZH uses is oil, so I feel good about deciding to lube the rifle properly.

I found the piston rod spring, "piston sear" and balls just sitting inside the main spring.

The sear (not to be confused with the trigger sear) parts.

The spring, oily and covered with dirty corrosion?

I tried as best I could to get that pin out but I couldn't. I didn't want to break anything so it's going to stay there. The pin retains both the piston head and piston rod.

Another steel and then polymer washer.

The piston seal is fine, you can see where it hits the transfer port. Like most IZH/Baikal airguns this one came with a spare seal, spring and a bonus of two more sear balls.

So the piston sear fits under spring tension into the piston rod.

And the balls go in the hole.

But how do I get the whole thing back together? This Russian Airgun Forum post had a hint... the piston rod bushing has a slit and can be expanded over the larger diameter end of the piston rod.

The bushing covers the ball holes, retaining everything.

That can now be slid into the spring guide.

Which pushes the bushing off of the end, and onto the middle of the rod, where I first found it.


And everything stays together. We'll see if it works as smoothly when I'm putting it all back together. I'm still a a little fuzzy on the ball sear mechanism. But the rifle is apart and that's 1/3 of the job done! (1/3 boring: deburring, cleaning and lubing, 1/3 reassembly)...