Impact m3 brass

The one above is for the plastic stem
Brass stem is
()()()()()()(
Hi airhead1956. For the brass piston (without shortening the piston), what thickness are the washers in your ()()()()()()( configuration? I'm not looking for specific caliper measurements, but rather just thin, medium, thick. I'm assuming there would be some thin ones on the left followed by medium ones in the middle and thick ones on the right -- but how many of each?

grungy
 
Hi airhead1956. For the brass piston (without shortening the piston), what thickness are the washers in your ()()()()()()( configuration? I'm not looking for specific caliper measurements, but rather just thin, medium, thick. I'm assuming there would be some thin ones on the left followed by medium ones in the middle and thick ones on the right -- but how many of each?

grungy
Same as the FX bellvilles
 
Hi airhead1956. For the brass piston (without shortening the piston), what thickness are the washers in your ()()()()()()( configuration? I'm not looking for specific caliper measurements, but rather just thin, medium, thick. I'm assuming there would be some thin ones on the left followed by medium ones in the middle and thick ones on the right -- but how many of each?

grungy
Each ( is one. They are the same as the FX factory
 
Howdy qball. I just received 2 stacks of washers from fx. Both stacks have 11 washers and are oriented as you show. Do the washers on the right go onto the piston first (up against the piston head)?

grungy


Pretty sure it doesn't matter as both sides have the same contact interface with the piston.
 
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Pretty sure it doesn't matter as both sides have the same contact interface with the piston.
Yep, same contact surface with the piston head and the piston shaft and the bottom of the regulator body either way. The reason I asked is because the fx stacks I received have thin washers on one end, thick washers on the other end, and medium thickness washers in the middle. This is similar to the progressive-wound springs found in the front forks of off-road motorcycles. The heavy/thick part of the spring should be up by the handle bars and the lightweight/thinner part of the spring should be down by the axle. The reason for this is that when the bike hits a bump, less spring mass has to move in order to let the forks compress and extend back to "normal". Because less mass has to move, the forks can compress and extend more quickly -- very responsive that way.

Obviously we are not dealing with a motocross bike here, but I'm gonna stack the washers with the light/thin washers closest to the piston head and have the heavy washers up by the bottom of the regulator housing. That is, unless someone tells me a reason it shouldn't be that way.

I would already know if fx intended to have the thin washers down at the piston head if I had not dropped the whole frickin stack when I took out the piston.

Thanks qball.

grungy
 
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@grungy: I see what you mean now and what you said makes a lot of sense. In Ernest’s video he mentioned that thinner washers(in pairs) at the middle and thicker washers at the end works better. However in my opinion/theory the each individual washers/springs pair all compress inline/individually in the stack or not compressing in parallel except the doubled up one at the end which means where the thinner washers are in the stack should not make any difference. To me the doubled up one is merely there to be a spacer. Obviously the washer stack is designed to be progressive with different thickness washers to handle 80-200 bars of regulated range which is impressive!!! In huma regs you have to change out the entire stack to accommodate relatively narrow pressure range. Fantastic engineering by FX as usual.
 
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Hi airhead1956. For the brass piston (without shortening the piston), what thickness are the washers in your ()()()()()()( configuration? I'm not looking for specific caliper measurements, but rather just thin, medium, thick. I'm assuming there would be some thin ones on the left followed by medium ones in the middle and thick ones on the right -- but how many of each?

grungy
All are medium
 
All are medium
Screenshot_20230513-073839_Gallery.jpg
Screenshot_20230513-073839_Gallery.jpg

Hi everybody.
Trying to follow Ernest's instructions in his video I placed the belleville disks like my photo above .
I have in stock many different disks from previous experiments all from fx and Huma mixed .
Starting from the head of piston 2pcs looking same direction ,one opossite ( 3 of them 0.55 mm).
Next 3 pairs 0.46 and Last pair 0.56
My new set up is on 180 bar for my impact x without any creep last month .
What impressed me more is that in my attempt to make lower my reg pressure and while i was trying to degass the plenum I turned counterclockwise a little bit the adjustment screw and after I degassed it instead of turning it clockwise I turned it accidently almost a full turn counterclockwise and the result was to rise in 240 bars .

( I wasn't focus enouth . All this happen while I was replacing my impact action, Easter night without electricity in the room just with a head light on my head and very tired. I posted before few weeks a thread with this story )

I got scared for a moment but I left it like this just from curiosity for a half hour just watching ( from a safe distance 😂) if I will have any creep.
Is amazing that kept this pressure without creeping or blowing an oring .
I returned the pressure where I wanted at 180 bars and so far after one month no creeping with same brass piston and is working perfect .

Is good to mention here that few hours before this happen I have changed all the orings with new on brass piston and in reg body .

Even with a little bit different disk thickness like 0.01-0.02 I believe it will work with same results .
I just used what I have available in stock .
In general I have to say after many many headaches since 2019 with huma regs and later with fx derlin pistons the new brass pistons are working perfect in high pressures.

After I installed first time the brass piston my impact was sitting in store almost a full year without any creeping at 185 bars .
I hope I helped with my post .

A very big "thank you " to Ernest for his amazing videos ! 🙏