Well, I was doing so good. Started playing again in October with Mags...only Mags. I figured them out and really enjoy them. Didn't have any reason for anything else. Why would I want something else? How many PB guns do I really need?
Then I started reading posts from you sumnabatches. Such bad influences one and all. I started reading about Pro-Carbines in particular. I used to have a bunch of Carbines. Never got a Pro-Carbine because the 98 was out and seemed to be the new standard for beaters. The more I thought about it, the more it gnawed at me, that I really want to try a Pro-Carbine. Now, a couple weeks later, I have 2 clapped out Pro-Carbines broken down and an Sa-200 arriving today. New seals for all are on the way, and I have been 3D printing the squishy bits. I figure I would make my own thread again for this insanity so my questions and stupidity don't clog up other people's.
The Cleanening
First thing was airing them up just to see if they still worked in such a completely fooked state. Sure enough, one held air cycled and shot (with a new detent) just fine. The other cycled just fine, but had a slow valve leak. I later found that the power tube was sheared off from it's base and was awol. The velocity screw was also broken off, with the tip stuck in the power tube base. When disassembled, the valve and hammer seals on both crumbled. Absolutely amazing that they still functioned as they did.
I am quickly finding out that these Tippmanns mean two things, rust and 15 year old paint. After soaking the shells of the foregrips for 2 days in dishsoapy water, I still had to use a steel wire brush to get to the bottom of that paint inside. I didn't know paint could do that. I soaked all the plastic screws in Evapo-Rust, which sorted them out. Got a bunch of stainless replacements for the rest. All the other bits were ultrasonically cleaned for an hour in simple green concentrate and then polished. I now have 2 good forends, 2 good grip sections, and one body that I would consider functional. The Sa-200 should give me a second. I am interested in checking out the valve differences.
Squishy bits
I downloaded some detent models, which I found to be ill fitting and didn't look like they would function well, so I made my own. About 4 versions later I had a model that fit the detent cutout on the carbine perfectly, and had a springy action. One addition for the 4th version was a tiny amount of structure under the finger in the area where it creases. The helps the tip be even springier and should help them last a bit longer. Not that it matters, because I promptly printed a few plates of 82 detents. I plan on putting a new one in every time I use one cause I can. My local field owner dug out some Carbine parts for me, including the power tube I needed. One part was a bumper that wasn't healthy enough to use, but still had its original shape for measurement. I made a model of it and printed it in TPU with single walls and top/bottom layers and open wavy infill. It would work fine, but I decided on another setup with diamond shape springs in a center piston and an outer rim as a final stop. Has the same outer dimensions as the original and a very nice action that should work and last well.
Power Tube Porting???
I'm not trying to make an LP gun out of a Pro-Carbine. I am trying to make sure they can all shoot over 300FPS with my 800psi output tank so I have some headroom to ensure they chrono to the field velocity. I plan on making RVAs for them, and have multiple long fresh springs to cut down if needed. I will drill out the gas fittings into the valve a bit. What kind of porting, if any, should I do in the back of the power tube? Should those four holes be joined into one by cutting out the center section or drilling one large central port? Or should I just bevel the four inlets to make a it flow better through them? Any tips about successful methods would be welcome.
That's as far as I have descended into the abyss at this point. All indications are that it will get worse.
Then I started reading posts from you sumnabatches. Such bad influences one and all. I started reading about Pro-Carbines in particular. I used to have a bunch of Carbines. Never got a Pro-Carbine because the 98 was out and seemed to be the new standard for beaters. The more I thought about it, the more it gnawed at me, that I really want to try a Pro-Carbine. Now, a couple weeks later, I have 2 clapped out Pro-Carbines broken down and an Sa-200 arriving today. New seals for all are on the way, and I have been 3D printing the squishy bits. I figure I would make my own thread again for this insanity so my questions and stupidity don't clog up other people's.
The Cleanening
First thing was airing them up just to see if they still worked in such a completely fooked state. Sure enough, one held air cycled and shot (with a new detent) just fine. The other cycled just fine, but had a slow valve leak. I later found that the power tube was sheared off from it's base and was awol. The velocity screw was also broken off, with the tip stuck in the power tube base. When disassembled, the valve and hammer seals on both crumbled. Absolutely amazing that they still functioned as they did.
I am quickly finding out that these Tippmanns mean two things, rust and 15 year old paint. After soaking the shells of the foregrips for 2 days in dishsoapy water, I still had to use a steel wire brush to get to the bottom of that paint inside. I didn't know paint could do that. I soaked all the plastic screws in Evapo-Rust, which sorted them out. Got a bunch of stainless replacements for the rest. All the other bits were ultrasonically cleaned for an hour in simple green concentrate and then polished. I now have 2 good forends, 2 good grip sections, and one body that I would consider functional. The Sa-200 should give me a second. I am interested in checking out the valve differences.
Squishy bits
I downloaded some detent models, which I found to be ill fitting and didn't look like they would function well, so I made my own. About 4 versions later I had a model that fit the detent cutout on the carbine perfectly, and had a springy action. One addition for the 4th version was a tiny amount of structure under the finger in the area where it creases. The helps the tip be even springier and should help them last a bit longer. Not that it matters, because I promptly printed a few plates of 82 detents. I plan on putting a new one in every time I use one cause I can. My local field owner dug out some Carbine parts for me, including the power tube I needed. One part was a bumper that wasn't healthy enough to use, but still had its original shape for measurement. I made a model of it and printed it in TPU with single walls and top/bottom layers and open wavy infill. It would work fine, but I decided on another setup with diamond shape springs in a center piston and an outer rim as a final stop. Has the same outer dimensions as the original and a very nice action that should work and last well.
Power Tube Porting???
I'm not trying to make an LP gun out of a Pro-Carbine. I am trying to make sure they can all shoot over 300FPS with my 800psi output tank so I have some headroom to ensure they chrono to the field velocity. I plan on making RVAs for them, and have multiple long fresh springs to cut down if needed. I will drill out the gas fittings into the valve a bit. What kind of porting, if any, should I do in the back of the power tube? Should those four holes be joined into one by cutting out the center section or drilling one large central port? Or should I just bevel the four inlets to make a it flow better through them? Any tips about successful methods would be welcome.
That's as far as I have descended into the abyss at this point. All indications are that it will get worse.
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