Fx crown Regulator creep???

[ImpactX]

Same thing happened on my impact x. Set reg shows 150. But if I shoot a few shots it drops to about 140 and stay there. And if I let it sit for few hours it goes back to 150. This is a fairly new gun. Had it for about 5 months. It has the amp reg. But the amp reg can is only good to increase or decrease reg without taking bottle off. It does not stop reg creep. I got tired of trying to fix the damn fx reg. I cleaned it,.lube it, flip bevels washes, double stack them. Nothing work. Was forced to buy a Huma reg. Cost $120 shipped. I'll report back when it arrives. Fx needs to use Huma in all their guns cause been years and they can't get it right. I expect reg creep on a $300 gun. But not on a freaking $2000 gun..smh fx. 

 

[Maddad]

I may be mistaken but I think this is the third attempt in the last three years by FX to create a regulator for the Impact and Crown that works as required without problems. It would have been so much simpler for them to just install Huma regulators at the factory level like Daystate and Brocock have done and the problem would be non-existent by now. And yet they stubbornly keep reworking a design that has not been problem free since the beginning. Maybe one day they will solve their regulator problems once and for all by just using Huma regulators...its funny that I have not heard even one complaint about the regulators in the Daystate of Brocock Air Rifles in the last year and a half since they started installing the Huma regs in their rifles.

I think you will need to compare sales numbers for a fair comparison in this one. I bet that the FX sales numbers far outnumber the Brocock rifles, if you take a percentage of 'faulty' regulators you will see a big difference in the actual amount of people and thus more people will apppear on the forums complaining.

The best remedy is to set the regulator and never touch it again if it seals! HuMa regulators work on the exact same principle as the FX regulators only they use a white soft material (I expect it to be POM or PTFE or something, not sure by the way) disk on top of the piston as a sealing surface for the regulator and the FX regulators use a soft material piston that will do the same job (don't know about the newest generation of FX regulators by the way). The inlet nozzles of the regulator will never be 100% concentrically identical straight out of the factory and thus if you change it's position it will have a different seating surface and this takes time to create. If it's seated but the surface is damaged it will leak. With the HuMa regulators you can turn the disk over or replace it and for the FX regulator you will need to change the piston. This problem will re-occur on every regulator that works this way, after a few adjustments and some arbitrary time the huma will start leaking too but you can extend this period by NOT touching it. I know this is perpendicular to the option of being able to adjust it but the regulator tip will wear during use and certainly while adjusting it too much. There are ways to work around or even solve this problem but that'll require some skills or maybe a redesign and a decent root cause analysis. I have some ideas for this but first have to test them myself too see if my suspicions are true.

Fx recommend that I change the piston the first time I experienced creep. There was nothing wrong with the original one. But after I cleaned and replaced it it was working fine at 140 bar. But now my problem is the reg dropping the set reg pressure. I think the set screw is loose and is turning when fired. I’m going to check this assumption. I’ll report any findings. 

 

[broekzwans]

Same thing happened on my impact x. Set reg shows 150. But if I shoot a few shots it drops to about 140 and stay there. And if I let it sit for few hours it goes back to 150. This is a fairly new gun. Had it for about 5 months. It has the amp reg. But the amp reg can is only good to increase or decrease reg without taking bottle off. It does not stop reg creep. I got tired of trying to fix the damn fx reg. I cleaned it,.lube it, flip bevels washes, double stack them. Nothing work. Was forced to buy a Huma reg. Cost $120 shipped. I'll report back when it arrives. Fx needs to use Huma in all their guns cause been years and they can't get it right. I expect reg creep on a $300 gun. But not on a freaking $2000 gun..smh fx.

Did you by chance tried to reshape the top of the piston? You can sand it down but there is a chance that the surface won't be flat anymore, a lathe or mill is better. That should have fixed the problem most probably

 

[broekzwans]

Fx recommend that I change the piston the first time I experienced creep. There was nothing wrong with the original one. But after I cleaned and replaced it it was working fine at 140 bar. But now my problem is the reg dropping the set reg pressure. I think the set screw is loose and is turning when fired. I’m going to check this assumption. I’ll report any findings.

Mark it with a small marker over the edge from the adjustment screw onto the body so you're sure you can see if it moved. Curious to see your findings

 

[Maddad]

Fx recommend that I change the piston the first time I experienced creep. There was nothing wrong with the original one. But after I cleaned and replaced it it was working fine at 140 bar. But now my problem is the reg dropping the set reg pressure. I think the set screw is loose and is turning when fired. I’m going to check this assumption. I’ll report any findings.

Mark it with a small marker over the edge from the adjustment screw onto the body so you're sure you can see if it moved. Curious to see your findings

Just put a little flag on the set screw and took a mag full of shots and that "isn't it" it didn't move but the pressure setting did, it went down to 145 bar again same exact thing that happened last time. 

 

[Maddad]

Very confusing the screw didn't move after a mag full of pellets but the pressure setting did, from 150 bar back down to 145 and used 250 bar to 220 bar from the tank. Tank pressure is normal. How can the reg be lowering the pressure it's self? I hate puzzles like this! Got to watch what i write and be more precise with my wording. 

 

[Bob_O]

Sounds like you need to check for leaks if the bottle pressure went down that much overnight.

Unless it just went down from a full mag of shots, then disregard.

 

[Maddad]

Good luck to anyone who can figure this out, I'm baffled and will be putting a Huma reg next week. I was wondering why I saw so many Daystate rifles in competition now I might be understanding why! FX has left a sour taste in my mouth for getting another one of their guns. To bad! 

 

[broekzwans]

Just put a little flag on the set screw and took a mag full of shots and that "isn't it" it didn't move but the pressure setting did, it went down to 145 bar again same exact thing that happened last time.

Have you measured the muzzle velocity by chance? I would advise you to monitor this when you see a pressure change, could be that's it's just the pressure gauge itself that inaccurate some times. If the muzzle velocity is the same I wouldn't worry about it, if not than please report here and we'll find a way to fix it

 

[Guest]

Jimmy King replaced the gauges on his Crown with Wika gauges awhile back by making the holes in the stock slightly larger...you may want to think about doing the same thing. But if you PM Jimmy and ask him if he is happy with his new gauges I am sure he will be happy to discuss it with you. I know the diameter of the Wika gauges is 28mm so you could measure the gauge holes in your stock to see how much you would have to open them up. And if you decide to do so, here is a place in the U.S. that stocks the Wika gauges...

https://palmbeachairguns.com/

 

[Maddad]

After testing the reg set screw and finding it hadn't moved and after looking the piston was fine just like new. I think it might be the spring washers are compressing more after shooting which means they're to week a spring for the job. That's my thoughts. 

 

[Maddad]

Just put a little flag on the set screw and took a mag full of shots and that "isn't it" it didn't move but the pressure setting did, it went down to 145 bar again same exact thing that happened last time.

Have you measured the muzzle velocity by chance? I would advise you to monitor this when you see a pressure change, could be that's it's just the pressure gauge itself that inaccurate some times. If the muzzle velocity is the same I wouldn't worry about it, if not than please report here and we'll find a way to fix it

Yes I was shooting over the crono and the the velocities were all over the place. Standard deviation of 9 was the best, worst was 18. I think it's week spring washers they compress and don't return, that's my thought on what's happening. 

 

[Maddad]

Jimmy King replaced the gauges on his Crown with Wika gauges awhile back by making the holes in the stock slightly larger...you may want to think about doing the same thing. But if you PM Jimmy and ask him if he is happy with his new gauges I am sure he will be happy to discuss it with you. I know the diameter of the Wika gauges is 28mm so you could measure the gauge holes in your stock to see how much you would have to open them up. And if you decide to do so, here is a place in the U.S. that stocks the Wika gauges...

https://palmbeachairguns.com/

Thanks for the info Chuck! 

 

[nervoustrig]

If the setpoint is adjusted too high, the Belleville springs may be squeezing flat and that could cause the pressure to become unpredictable, or it could cause the regulator to go into bypass mode...but they don't "compress more after shooting".

 

[Maddad]

If the setpoint is adjusted too high, the Belleville springs may be squeezing flat and that could cause the pressure to become unpredictable, or it could cause the regulator to go into bypass mode...but they don't "compress more after shooting".

The FX reg is suppose to handle 150 bar and the AMP is supposed to handle even higher 160 or more. Yea I really meant that the springs are probably staying compressed after shooting, maybe to week of a spring washer. I'm putting in a Huma reg tomorrow so this is going to be a moot point. 

 

[nervoustrig]

If indeed the problem is caused by the springs going flat, that could be corrected for about $10 for a package of thicker Bellevilles.

 

[Maddad]

If indeed the problem is caused by the springs going flat, that could be corrected for about $10 for a package of thicker Bellevilles.

You would think if that's it, FX would admit it and should replace them for nothing. But have heard nothing but just reset the reg, from them. 

 

[nervoustrig]

Exactly. The widespread creeping issue is not because of the springs going flat. It's the valve seat just as it is with virtually every other regulator that creeps.

 

[Maddad]

Exactly. The widespread creeping issue is not because of the springs going flat. It's the valve seat just as it is with virtually every other regulator that creeps.

I don't know if I would call this creep exactly, creep to me, would be that the reg increase the pressure while sitting, and that would be easy to fix, clean it and maybe a oRing or two. That's not what's happening with my reg. I set the pressure and after shooting the Set pressure has dropped, it's a constant drop too 150 bar to 145 bar for one full mag and with two mags it drops to 140 bar. I can reset it up to 150 bar and the next mag full it's back down to 145 bar. And it doesn't move back after sitting. Anyway FX needs to do some work on this thing or just get HUMA to do it for them. 

 

[nervoustrig]

Oh okay, yes that sounds like something different. You are describing an inconsistent setpoint or a drifting setpoint. That could be a result of being near the limits of the Belleville stack as previously stated, or it could be something that is causing the spring rate to vary each time the regulator cycles open and closed. At least one design iteration of the FX regulator had a lot of slop between the piston's OD and the ID of the Bellevilles. That would allow the washers to slide laterally relative to their neighbors, thus the spring rate may vary from time to time. It's hard to say without some trial and error experimentation.

With that said, for a variation of only 10 bar, it should be possible to tune the gun to be agnostic of it. An unregulated PCP that is properly adjusted can hold a 1 - 2% ES over a range of 20 - 30 bar, sometimes more. A regulated gun that varies by 10 bar is technically no different from an unregulated gun that is operating over a pressure range of, say, 150 -> 140 bar.

By the way you stated again that if the problem were creeping that it would be easy to fix by cleaning and some O-rings. That's almost never the case and I fear that it may mislead others who are reading along.