Rainmaker POP build(s?)

[Rainmaker]

Received my pile of wonderful rental goodies last week and got to work with the cleaning. I was able to get one of them aired up and cycling with no leaks on all the stock parts! So that's pretty exciting!
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[Rainmaker]

I have two ideas for the build. The first one i think will be pretty do-able: A binary trigger (one shot on trigger pull, one shot on release). I have a few ideas on how to accomplish this, the first of which is to put a ball bearing in a channel under the firing "pin", and mage a sliding trigger rod with two cuts in it, and a hump in between. that way the ball passes over the hump one time in each direction of the trigger movement. (Pics below).

The other idea i have for the build is still top secret (mostly because I really don't know if it will work or not... and I don't want to spread any premature hype). But as a teaser, the concept includes the addition of an additional fluid to make the gun function. A fluid that has never before been used in the operation of a marker. (cue the crude jokes, i'm sure)

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[Magmoormaster]

Well color me intrigued!!!

[BrickHaus]

Ahh, a Master of the poo already at work. Looking forward to your builds

[OpusX]

Okay now this is going to be fun.

[StaticShocked]

That is very clever! I am really looking forward to seeing more.

[The Hobbit]

Hydraulic valve activation?

[_Boris_]

I was thinking propane or butane as propellant ... that would make it a firearm tho

[Rainmaker]

Did test print section of the frame and trigger and put the rods and brass bushings in. Trigger moves well! I’m using a 6mm Airsoft bb for the plunger bumper. Need to figure out a little trigger retention screw and grind the bumps into the lower rod to bump the bb.
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[RPP]

Looking awesome.

[Rainmaker]

Been busy with work and family, but this morning I made some tweaks to the grip frame and started the print.

[Rainmaker]

So, grip frame printed, parts assembled... I had a few minutes to mess with it last night and it looks like I have a few issues.

One is that I need to work on the "bump" profile of the trigger rod (that bumps the ball up and down). It's not quite bumping the pin up at the right part of the stroke.

Another issue is that the grip frame print has a few off-dimensions, and a couple spots where I need to take off material to get the fit just right. I kinda don't want to do a whole re-print, so I'm just going to do a bit of dremel work and see where that gets me. (then update the solid model after).

The other is that I have some intermittent bolt stick. I think I just need to re-clean the bolt engine, and use less lube.

But on the positive side, it shoots! It doesn't Binary yet, because of the trigger rod "bump", but i feel like i'm close

[FredMnkyDad10]

Awesome stuff you got going. Look forward to more.

[Rainmaker]

I'm going to re-print the frame after all. I got the marker to cycle, like I mentioned above, but during the travel of the trigger, the triggering rod with the nubbin deflects downward due to the amount of force required to push the ball up into the valve actuator. So i am modifying the rod housing to be fully supported by the brass bushing. Makes it a little more complicated than I was hoping, but it should work better. Also revised the nubbin profile and position and lengthened the travel of the trigger pull.

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[StaticShocked]

This is so neat. Can't wait to see it in action!

[tyronejk]

I wonder if that nubbin "peak" is too sharp and will make it easy to short-stroke. I'm thinking of situations where you might pull the trigger very quickly (e.g. hard quick pull) and not open the valve for long enough. This could be fixed with a plateau on the nubbin. But it may not be an issue in practice.

[Rainmaker]

That’s a good point, I may have to play with both the trigger stroke length, and the nubbin profile. Gonna try to get the frame reprinted this weekend

[Rainmaker]

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reprint of the frame is done! fits up pretty nicely, and I made sure it cycles normally before putting in the binary pieces. I cut the new brass busting for the trigger rod, and the trigger slides nicely. Now just need to mess with the nub profile to get it to double tap

[Rainmaker]

This is where I stand right now. The binary rod needs some grinding to get it just right, I just haven’t hat the time to work on it. I get shots, but the bb stays in contact with the valve too long and makes it leak at all times. And needs grip panels too.
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