Tuning Tuned valve seat and valve pin question

[wildscorpion]

I have FX Dreamline, its valve seat is nightmare. In less than 200 diabolo fired it start to leak slowly. So far i have changed two seats and ordered new one, same thing happen with new installed one so i wanted to tune my valve and make new valve seat and pin which will give me more power or shots and will be durable. The problem is with cone part, I can not get it right without leaking so i have one idea how to possible solve this problem but i do not know will it work so i am asking for answers here.

here are original parts and moded parts by me

this are moded parts only

What i should achieve with this mod is more power and durability. More power because internal hole of my seat is 6.5mm while original was 5.5mm so i can reduce hammer spring tension to prolong valve seat lifetime and still get more power in the same time. My problem is that even i match angle of both cones (pin and seat cone) i still have air leak so big that i can not pump the tank. So i get idea to make both pin and valve coneless and instead of cone use o-ring on flat front surface of valve seat like this:

I want to make a channel arround the seat hole and insert in it o-ring so seat hole would be closed by flat front surface of valve pin. My question is: is this worth to try? Will it work?

 

[nervoustrig]

Burnish the valve seat components together with a fine abrasive like J-B or a fine metal polishing compound. Chuck up the valve stem in a drill and spin it against the seat. Go slowly and frequently replenish the compound so as not to generate too much heat that you risk melting the plastic part.

When you think you've done enough, color both surfaces with a magic marker and do another short pass with the abrasive. When it neatly removes the marker with no visible scratches, you can tell you've done enough.

I wouldn't advise using an O-ring as a valve seat. Yes it will provide a more forgiving seal...it will solve the leak but it will make the valve vastly harder to knock open which means you'll need a tremendous amount of hammer spring tension to make it work.

 

[wildscorpion]

thank you for advice!

 

[biohazardman]

I have done what nervoustrig recommends on several valves, not FX units but still, it will get rid of any surface scratches and slight defects. It werqs well. Make sure you have the right o-ring installed on the removable valve seat as it is a very precise fit.

 

[wildscorpion]

@biohazardman i tried several o-rings for my removable valve seat and used one that is best sized for internal size of my gun, i am pretty sure it holds pressure well. So there is only one place left where my valve could leak ( cone part on my valve seat). I will try to polish both parts as both of you suggested. Thanks for reply!

 

[bigHUN]

Burnish the valve seat components together with a fine abrasive like J-B or a fine metal polishing compound.

This "laping" the mating surface together with some fine valve grinding compound and check with some pigments like lapping blue