Those poppets look like aluminum? What is your sealing surface? Are you just cutting a groove and using a oring? Thanks for sharing your work in progress.
May I point out that you no longer need to drill the valve stem with this design. A simple hole through the valve face works just as well.
A practical question, how thick walls do we need for that poppet "cup" if we use PEEK? Will 1mm do, i.e. 6.5mm poppet and 4mm plunger inside or do I need to expand the poppet diameter once the hollow inside starts?
The bigger the OD, the thicker the wall needs to be (in direct proportion).... You would need to know the tensile/compressive strength of PEEK to calculate it.... I can understand the reason for wanting to use PEEK or Delrin for the poppet.... not having to make a seat insert for the valve to use a metal poppet.... One less part to make, and one less O-ring to leak (seat to valve body)…. On the other hand, then you have the structural problem of mounting the PEEK poppet head/cylinder onto the metal stem.... without having it thrust through on firing.... Bob
Ok ... made one more tho this time around changed materials and specs as to make a valve that had the specs of this one: https://www.gatewaytoairguns.org/GTA/index.php?topic=160999.msg155792422#msg155792422Above Referenced thread and that valve opening with a mere 43% opening force of conventional valve, able to use a 20 gram hammer, easy one finger cocking etc ... had to see if a valve built to the REVISION specs would work the same ?I used a JSAR SS 1 valve body that has a throat of @ .320" with .250 big port transfer. Specs here are about identical to a modified WAR valve in above Ref: thread.This time tho the poppet head was 100% Glass filled acetal rod that when assembled tipped the scale at just 3.8 grams being lighter than OP version. Chamber bore opened up to .250" and poppet O.D. at .365" giving us @.022" sealing margins.The chamber stem attaching to intake grate now aluminum and got an o-ring groove for "006" series o-ring * Tho used a QUAD RING which is ideal for this dynamic application.Exterior spring design stayed intact, as did the adjustable preload / chamber volume threading.Put it all together adjusting the chamber rod to just bottom out at near zero volume when poppet stem is flush to body. Total available poppet lift @ .170" ( Amount extending out for hammer to strike )Aired up with a slight leakage until @ 600 psi and then it stopped once above that. Man does it open easy !! being just like the WAR valve, near identical too.Assembled the WarP with the light hammer, light spring SSG and an extension on striking tip to destroke hammer travel, along with a taper choked transfer port at .165"2000 psi reg setting and first shot with 21.3 barracuda .. 1070 fps, 24.8 Nielsen slug 960 fps. That was too easy !QUIET TOO being IMO sounding as if using even less air than previous where my RAPTOR spec valve had been previously and indeed quieter than the modified WAR valve.YES IT WORKS turning the valve around aka: "REVISION" and in the future think I'm going to stay the course and make them this way from now on ... it is actually easier to fabricate too ! Scott S