Today, I took apart a Ninja regulator and rebuilt it for inline use.... It looks like these other ones I have done previoulsly....
The modifications I made are as follows.... Do this only if you are competent working around HPA, and at your own risk.
1. Completely disassemble the regulator, removing both burst discs, the male Foster and the gauge from the reg. body.
2. Cut off the threaded stem that screws into the tank just below the safety vent hole.
3. Drill the bottom of the body to 11/32" until you just touch the three cross holes that pass air to the fill, gauge, and HP burst disc, and tap 1/8"-27 NPT.
4. Deburr and use compressed air to blow all debris and chips out of the regulator body, and install a plug, using Teflon tape to seal it.
5. Reinstall the male Foster (with NO check valve) and gauge, and install burst discs of the appropriate rating for the inlet and outlet pressures.
6. Remove the pin valve from the bonnet, and drill through 11/32" and tap 18"-27 NPT. Remove all debris and chips with compressed air.
7. Install a female Foster in the bonnet. I used a close hex nipple because I didn't have a female Foster with male threads. Both Fosters should be rated for 4500 psi.
8. Install new O-rings on the regulator piston. I would recommend using a Ninja rebuild kit from Mac1 Airguns, which comes with 90D Mil-Spec Urethane O-rings.
9. Install a Belleville washer stack appropriate to the pressure range you need, with appropriate shims, on the piston.
10. Install the piston in the reg. body and screw on the bonnet.
11. On the output side, attach an accurate gauge equipped with a bleed valve to the female Foster.
12. Fill slowly through the male Foster using a tank or pump, to 1000 psi, and check for leaks. Repair if necessary.
13. Slowly increase the pressure at the inlet, while watching the gauge. If you increase the pressure too close to the rating of the outlet burst disk it will fail.
14. If the burst disc fails, change your shorts, then change the disc, reduce the shimming in the regulator, and repeat.
15. If the indicated output pressure is too low, shut off the tank, bleed the system, and increase the thickness of the shims. If too high, remove shims.
16. When you have the regulator adjusted to the setpoint you want, "burp" the bleed valve a few times to settle the needle, and the reg. and double check the pressure.
17. Once you have the regulator adjusted the way you want, close the tank valve, and bleed the system. Record your Belleville stack and shims for future reference.
18. You can now tether your gun to the output side of the regulator with a HP hose, and when you turn on your tank, your gun will fill to the setpoint pressure.
19. If your gun has a pressure gauge, fill slowly and double check that its gauge is close to what you read on your quality gauge. They may not agree exactly.
20. Enjoy shooting your gun tethered to your tank. Ideally, the burst disc on the output side of the regulator should be close to, or only slightly above, the MSWP of your PCP, in case the regulator fails.
Although you have to change shims to alter the regulator setpoint, this makes a great inline regulator at far lower cost than the $300 plus adjustable variety.... The regulator for my Monocoque is set at 3800 psi.... This required a very unusual Belleville stack to achieve that high output pressure, consisting of five pairs of Bellevilles, with each pair consisting of a 0.047" nested inside a 0.032".... and then two thick Ninja 0.020" (red) shims, arranged like this.... The flat shims are inside the regulator body, with the opposite end of the stack against the large end of the piston....
| | ) ) ( ( ) ) ( ( ) )There are two BIG warnings about using this setup.... There is very little total travel, only 0.060" from loose to fully collapsed.... The pairs of Bellevilles take a huge amount of force to drive them flat, about 860 lbs., and that only takes 0.012" of movement per pair.... This means that EVERY 0.001" of shims changes the output pressure by about 90 psi.... Just a few thou of shims can make the regulator go from 3000 psi to not regulating at all, and passing the full tank pressure through to the output.... Most Belleville stacks are not this harsh to adjust, but when you need to go to high pressures, they get very fussy.... My regulator has a steel bonnet, I don't know if the aluminum bonnets found on some regulators are strong enough.... but Ninja sell regulators with the output set as high as 3000 psi, and having a 5K burst disc on the output side.... If they failed, they would pass the 4500 psi tank pressure through to the output side, and I trust Ninja to know what they are doing.... so I personally have no problem with such a high setpoint.... but I am NOT recommending that you do the same....
Bob