jackssmirkingrevenge wrote: ↑

Fri Feb 26, 2021 7:43 am

Took it down to 600 psi and the results were very different:

So when do we get to see the unbalanced spool valve that opens with the anemic 19th century hammer at 3 kPSI?
(just kidding)
Good job noticing what the problem was. Much better fix than machining a spacer.

Neat! We need a few more details on how it works, it looks like there's 3 sprinkler valves and the chamber can't be the whole length of that bottom pipe (or could it?). Only suggestion I have is to pneumatically pilot the three valves instead of electronically. You can hear the diaphragm "honking" t...

You could also spring-load them or even just add a larger handle to the valve as well. I think with a few bucks worth of tubing/fittings, and a small 1/4" ball valve, you could really make those three sprinkler valves work a lot better as well though, all depends on what you want to do.

Just as a matter of opinion: cam locks all day every day. In a mounted configuration like yours screw breech works well enough, but any usage where the barrel is free to move in any other axis than forward/backwards (and rotating) they become very annoying.

The temptation is always there to "count out" electronics as innovation, but with the energy density (and miniscule internal resistance) of modern batteries getting better and better, things like direct-action solenoid hammers and electromechanical loading could probably (definitely) lead to obscene...

You want the barrel seat (outlet) and the piston to be closer in size for higher opening pressures for a given pilot pressure. To get the cracking pressure of your valve it's just P_c=(P_p*A_p)/A_c, where: P_c=cracking chamber pressure P_p=pilot pressure A_p=pilot area A_c=chamber area So with an 8m...

Ah, so you're using a chamber/outlet sealing design. That makes more sense. So are you trying to find the right sized piston so that you can use equal (before ignition) chamber and pilot pressures and still get opening at an optimal (higher) pressure? If so you could probably play around with GasEq ...

I think it will too. For whatever it's worth, I say mount the barrel with the seam at the top and pray for a backspin.

Weaponize the water heater.
In other news dope wall.

It might be worth giving this a read, or at least a quick skim: FM 3-22.90.
Not too familiar with mortars myself, as the only time I got to watch a team they fired a total of two flares.

It looks like he's using 3 18650's in series so I would go ahead and wager most 3S RC batteries could do the job.

Yes, I am bumping this thread because I missed the final product after my annoying suggestions. Great work as always!

I would say red chef caliber is more available at my local supplier than russet.

joergsprave v.2 incoming.

jackssmirkingrevenge wrote: ↑

Thu Aug 19, 2021 11:32 am

KeyMod

Quad rails god rails.