Anyone know where to buy a brass AMP piston?

MACTEN

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Nov 18, 2020
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I keep seeing pics of brass amp pistons. I know Huma has one installed on their AMP replacement but was wondering if someone was making these on a lathe out here. This is on the dreamline with the newest version AMP and I don't like the creep. I'm associating it with the OD of the piston as I changed out the inner reg body o-ring and still get creep. The piston body was smoothed out with no OD diameter loss as I used microfiber cloth at 18,000 grit..Just got it a little smoother.
 
The brass piston is available directly from FX, or seek out AGN member Seeker who has produced some.
I'm associating it with the OD of the piston as I changed out the inner reg body o-ring and still get creep.

Neither the piston OD nor the O-rings have any meaningful influence on creep. Creep is the result of how the end of the piston meets the valve seat. To halt the flow of air neatly and definitively, both surfaces should be smooth and flat...free of any machining marks, scratches, or indentation.
 
The brass piston is available directly from FX, or seek out AGN member Seeker who has produced some.


Neither the piston OD nor the O-rings have any meaningful influence on creep. Creep is the result of how the end of the piston meets the valve seat. To halt the flow of air neatly and definitively, both surfaces should be smooth and flat...free of any machining marks, scratches, or indentation.
I'll try to locate seeker. The mating surfaces are free of defects.. Are you speaking of the valve seat located inside the receiver in front of the plenum that allows air to escape from the plenum into the transfer port? I know the end of the piston and the end of the adjustment screw are both smooth where they meet as well as the surface of the actual piston.
 
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I know the end of the piston and the end of the adjustment screw are both smooth where they meet
In that case you've likely done all you can do to maximize the performance of that particular regulator. The only other question I would pose is how much opportunity has it had to iron in since you did the work to it? Meaning in terms of times fired (i.e. reg cycled open and close) and days left idle at elevated fill pressure? Those are the two primary things that influence the break-in period.
 
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In that case you've likely done all you can do to maximize the performance of that particular regulator. The only other question I would pose is how much opportunity has it had to iron in since you did the work to it? Meaning in terms of times fired (i.e. reg cycled open and close) and days left idle at elevated fill pressure? Those are the two primary things that influence the break-in period.
It may not be broken in yet. It' only been fired about 5-600 times and only left at topped up fill pressure for a week or so.
 
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Here is your request.

FX-USA
#19696-M
Regulator Piston Brass
$10.26 ea


Patrick

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