Saturday, September 5, 2009

Gamo PT-800 Pistol Reassembly (Daisy 1140)

And now to put the pistol back together.

The spring ends were rough so I smoothed them out.

Likewise with the top hat and spring guide.

Everything stuffed back in, then I screwed the end cap back on.

I temporarily screwed the pivot bolt back in and mounted it to the frame.

I think this is how the safety goes...

The trigger return spring goes over this piece.

Sear- trigger linkage parts mounted.

And spring in place. But the trigger doesn't look right.

Ahh, so the trigger goes above the safety, as shown. The bent part of the linkage goes into the trigger slot. Then I put the grip frame back on.

Yes, after a bit of searching on the bench I found the tiny circlip for the sight and put it together. The pistol functions and is a good can plinker.

Friday, September 4, 2009

Gamo PT-800 Pistol Disassembly (Daisy 1140)

I've been a bit busy lately but figured I'd drag out the Daisy 1140/Gamo PT-800 and take it apart.

Daisy branded, but made by Gamo.

I took it apart 10 years ago and the pivot bolt had a boss around it to keep it from rotating. It had worn off and I trimmed it flush to the body.

I remove the screws.

Then the pivot bolt.

I had to hold the other end with parallel jaw pliers.

Pivot bolt removed.

I tried to take the sight off and the little circlip on the end went "ping" and flew off. I'm sure I'll find it.

The housing opened.

The groove on the end of the sight for the circlip.

The trigger removed.

A pile of parts. This is one of those airguns where all the internal parts sort of explode out when you open it up.

The cocking slot.

The breech plug that retains the spring is white plastic with a square recess.

A 1/4" driver fits barely, it's probably a 6mm recess.

Very little preload. Notice the square coarse thread.

The piston assembly.

Spring with tophat and spring guide. These add to the weight of the pistol.

The piston is molded plastic with a molded insert for the cocking slot.

The piston seal is an o-ring of some sort.
I'll reassemble it in the next post...

Wednesday, September 2, 2009

Terrible Stock Repair of a Diana Model 45

Let me just say that, unlike Derrick, I am not the world's best woodworker. So this project will have you shaking your heads in pity. I did learn one useful thing though.

I bought this Diana Model 45 rifle at a gun show last winter. The price was low because there was a chip out of the stock.

I cleaned up the chip (which someone had started to clean?)

I slowly fitted a piece of maple into the recess.

Seems to fit well.

I then epoxied it in place. I think that this is where I made a mistake and the clamps somehow allowed it to twist up a tiny bit...

I covered the stock with masking tape so as to not accidentally scratch it. I then planed off most of the wood with a chisel. The rust on the chisel is due to a mouse problem. I hate mice.

I then finished by filing and sanding.

It looks ok at this point.

But close up you can see a dark epoxy line around the entire patch. Steel wool and sanding just brought it out further.

The one success I did have with this project is the color.

I found that my local hardware store had a variety of 29 cent samples of various stains. So I picked up four that seemed close to the stock color. This is the one I ended up using after testing on a piece of scrap wood. Definitely better than spending $5.00 for a can of stain that may or may not be right. The quantity is more than enough for small repairs like this and I was able to seal it by folding it over and clamping it shut with a paper clip.

I may revisit this repair later, seems like it would be a good idea to make a router template for both the patch and the stock to more precisely fit them together. Or paint the entire stock with truck bed liner.

Monday, August 31, 2009

Crosman 600 Grips Part 2 Final

Sidebar/Abstract: Anyone else notice (besides me) that I only seem to make asymmetrical grips? I was thinking about that the other day, and I think it's because I only shoot pistols offhand. With all those years shooting National Match courses, single-handed was the only way we were allowed to shoot. From a grip making standpoint, it's easier (in a way) to make asymmetrical grips. It's really difficult to cut 2 separate pieces of wood, inlet, then make each the same dimensionally on the exterior. Far easier to cut each piece slightly (or largely) different to account for the nuances of your shooting hand. The hard part when making asymmetrical grips is getting the halves to look like they belong together. This suddenly comes crashing down to aesthetics--something I mention often because it's important. And it's where I struggle whenever I make a grip or turn a piece of metal. We (I?) want our guns to look as good as they shoot. Well, I'm off topic and all over the place as usual. This stuff is all sort of interrelated anyway, right? OK, focus. My hand isn't symmetric, so why should me grip be? Anyway, that's what I was thinking about. Much of this thought stems from making that match grip a couple weeks ago. I spent some time looking at various orthopedic grips from companies like Nill-Griffe, Cesare Morini, and Rink. Pretty much what I learned was that their combined knowledge of the human hand is absolutely staggering.

Anyway, on with the show:

Sanded the formerly angular thumb rest into a continuous curve that terminates at the heel.

Re-profiled the top of the right grip to better match the left side.

The left side's top was pared down to almost no thickness--and no bulge--to clear my thumb. The right side needed to follow suite in order to match.

Left grip ready for finish sanding.

Took a while to remove all the sanding drum marks. I started with 100 grit garnet paper and worked my way up to 320. Did the same to the right side grip. Kept the grips flat on a piece of granite so as to not sand angles at the base.

Final fitting and ready for a finish. They're a bit longer at the top than the stock Crosman 600 grips. The threaded bushing and pin holes from Part 1 made for a no-wiggle fit.

Went with 3 coats of Minwax cherry followed by 3 coats of Minwax polyurathane. Synthetic steel-wooled between coats of poly. Essentially, I used the poly as a grain filler.

A couple (like three) coats of Minwax paste wax and I called it good. The right grip is pretty plane jane--just like the original.

A view from the rear shows how the curves match from left to right. This is what I was blabbering on about up in the first paragraph. I was having trouble bringing the grips together into a set. Each grip looked fine individually, they just didn't look like brothers. The key was reworking the swell at the heel on each side and playing with the curves a bit more. I tried to keep the thickness consistent from top to bottom on each side.



The guys at the hardware store said they never sell paste wax anymore. The old price on the can bears that out. It was about $3 less than current cost. I like the idea that I was using a finish my grandfather would be familiar with.

Excuse the barrel length. I had Ron Sauls at B&A cut down one of his extended gas tubes by about three and a half inches. I've not yet made a barrel to fit. I'm considering a few options to extend the muzzle.

Can't get the camera to convey all the curves.



The front of the left grip is concave then it blends into a convex curve near the midpoint.
These were supposed to be quick and easy. The big time hurdle was the thickness difference between the left and right sides. I started with a 1/2" board. The thumb rest easily adds 9/64" in thickness to the left side. If I make another set, I'll plane down the right grip by that amount and save a boatload of sanding time.