Diana Mod 34 Piston Seal

It's a pretty simple print. I used TPU 95A with 100% infill at a .12mm layer height on my Ender 3 V3 SE and it printed in 21 minutes and only used 3 grams of filament. 

It's not easy getting the new seal on the piston. I got it started on one side, worked it around as far as I could and then carefully used a small flat head screwdriver to get the last bit in. 

The outside diameter is 28.5mm tapered down to 27.5mm

I have a Ruger Air Hawk that has worked flawlessly for years. It has been sitting in my  gun safe for awhile and I decided to get it out. I was sighting it in with my son and all of the sudden we weren't able to hit the paper anymore. After a few more shots I noticed that the pellets were hitting the ground about halfway to the target that was only 25 yards out. 

I disassembled the gun apart, pulled the piston out and the seal stayed in the cylinder. Once I got the seal out, that was not the easiest thing, I saw that the inside of the seal was worn out and not staying on the top of the piston. 

After some searching on the internet, I was able to find a few seals. They ranged in price and would have cost over $20 to be shipped. I thought that was a little steep, so I turned to the 3D printing community and found a few piston seals, for different models, and it seemed like they have had success. Since I wasn't able to find one for my model, I decided to design one, print it and share it. 

I've only put about 50ish pellets through it so far, but it is working as it should. I don't have a chronograph, but it feels like it has more power back like when it was new.