Neat weird piston in classic valve… silver?

[pneumagger]

Rebuilding two Minimag valves and one of them has an interesting 2-piece reg piston.

its got a silver (nickel coated) body with a brass center insert (?). Never seen one like this. And much of the other orings in this valve were cracking and nearly rotten, too. So it’s probably pretty old. The other valve has a normal looking brass piston with the ring (high pressure?). The brass piston has and OAL of .735” and the silver one has an OAL of .760

Since I’m rebuilding both valves with Level 10, I shortened the silver piston set screw to increase the spring pressure, too.

[tunaman5]

The silver ones were the newest variation. Been around for years. By adjusting the set screw on the silver one you just ruined the safety mechanism. They are properly set when they leave the factory. Leave them alone.

[LukeAO]

TK told me the reg piston "blow off" was NEVER a safety feature (I always thought it was) he said it was just to alert you the regulator had failed. Truth is the new RTP pistons dont vent in the range they did when TK ran the operation, now they go WAY over in pressure/fps, like 400 fps over the chrono before they start to vent...

[tunaman5]

TK told me the reg piston "blow off" was NEVER a safety feature (I always thought it was) he said it was just to alert you the regulator had failed. Truth is the new RTP pistons dont vent in the range they did when TK ran the operation, now they go WAY over in pressure/fps, like 400 fps over the chrono before they start to vent...

The blow off range is now way higher because the Level 10 requires it

[Trbo323]

The blow off range is now way higher because the Level 10 requires it

And paint got smaller. Put today's paint through a classic mag with a twist lock and it won't make velocity so you crank up until you do and sometimes it starts venting

Op- don't worry about it, I took mine apart when I got my mag because I'm curious Jorge and it's been fine ever since.

Sent from my motorola edge 2024 using Tapatalk

[pneumagger]

And paint got smaller. Put today's paint through a classic mag with a twist lock and it won't make velocity so you crank up until you do and sometimes it starts venting

Op- don't worry about it, I took mine apart when I got my mag because I'm curious Jorge and it's been fine ever since.

Sent from my motorola edge 2024 using Tapatalk

And that’s why I adjusted it a little bit… I’m using level 10 in them.

And if venting ever does get to be a problem or the urethane in the pistons rots out… I’ll just make a new solid pistons out of 7075-T6 barstock.