Well, thanks to another fine member, here on AGN, a pristine, but ailing, RWS Diana 6G arrived at my doorstep Thursday and coincidentally, so did the seals from John Maccari. Those were ordered as a preemptive strike as the guns are known for the piston deteriorating.
This morning I decided to delve into a Giss system. Having never opened up a springer of any kind, I figured it would be a great learning opportunity.
It turns out it isn't rocket science, one pinion cap had to be helped loose with some Vice Grips and aluminum shim to avoid marring the surface. Same with the end cap, but I held that in the lathe jaws.
I found the replacement rear seal acts as a a perfect spacer to preload the spring enough to remove the sprockets without any tension. I measured the position of the end cap to go back to that position on reassembly, so I keep the gear timing from being lost.
When I opened it up, I will admit I fumbled the spring and that gave me a chuckle, but nothing took flight. The front seal was not on the piston, it was a chunky mass at the front of the compression chamber, most of it came out with a sharp rap and the rest got knocked out with a copper rod.
I cleaned everything and pressed the front seal in place and checked for fit. It was tighter than I felt was necessary, so I spun it on the lathe and shaved it down with a vixen file slightly to get the fit better.
It went back together without any fuss and all was well, except... I forgot to order a new breech o-ring
. I figured it would be a common size and I was wrong.
It sounded like a squeegee when I cocked it, but it fired just fine and started to quiet down after a dozen shots, but that's when I noticed that there was a little puff of air at the breech, so the real test will have to wait until I get a new breech seal and check velocity.
All back together and looking nice.
I hope that people will not be intimidated with tackling one of these guns if it needs seals. I spent about an hour and a half from start to finish and other than taking advantage of the three jaw chuck to hold the end cap, I used basic tools and a vise with the jaws lined with aluminum can strips to prevent damage to the finish. Sizing the seal didn't require the use of the lathe, it just kept it simple.
I'm looking forward to finding out how it will perform, I just like these older guns, the quality is always a treat.
Mark
This morning I decided to delve into a Giss system. Having never opened up a springer of any kind, I figured it would be a great learning opportunity.
It turns out it isn't rocket science, one pinion cap had to be helped loose with some Vice Grips and aluminum shim to avoid marring the surface. Same with the end cap, but I held that in the lathe jaws.
I found the replacement rear seal acts as a a perfect spacer to preload the spring enough to remove the sprockets without any tension. I measured the position of the end cap to go back to that position on reassembly, so I keep the gear timing from being lost.
When I opened it up, I will admit I fumbled the spring and that gave me a chuckle, but nothing took flight. The front seal was not on the piston, it was a chunky mass at the front of the compression chamber, most of it came out with a sharp rap and the rest got knocked out with a copper rod.
I cleaned everything and pressed the front seal in place and checked for fit. It was tighter than I felt was necessary, so I spun it on the lathe and shaved it down with a vixen file slightly to get the fit better.
It went back together without any fuss and all was well, except... I forgot to order a new breech o-ring
. I figured it would be a common size and I was wrong.It sounded like a squeegee when I cocked it, but it fired just fine and started to quiet down after a dozen shots, but that's when I noticed that there was a little puff of air at the breech, so the real test will have to wait until I get a new breech seal and check velocity.
All back together and looking nice.
I hope that people will not be intimidated with tackling one of these guns if it needs seals. I spent about an hour and a half from start to finish and other than taking advantage of the three jaw chuck to hold the end cap, I used basic tools and a vise with the jaws lined with aluminum can strips to prevent damage to the finish. Sizing the seal didn't require the use of the lathe, it just kept it simple.
I'm looking forward to finding out how it will perform, I just like these older guns, the quality is always a treat.
Mark
