Mechanical FASOR - Is it possible?

[SR_matt]

I have been daydreaming procrastinating getting back to work and ended up pondering a thought.

Would it be possible to make a FASOR marker (like the wrath) a mechanical? I know Ions have been converted to a mechanical but it seems like to do it properly you essentially change it into a sealed dump chamber to get rid of the dwell issues. With a FASOR obviously if the hammer is held forward longer then the valve gets held open and more air comes out causing issues. Is there any trigger valves around that are metered in a way that would apply X volume of air to the ram and then auto vent or would it end up needing a fully custom system?

Of course I am not doing this at any point soon but pondering a build is almost as fun as actually doing a build so why not think bout how it would work.

[DieManInTheRough]

I am not super versed, but am looking into doing something similar, with pnuemags and some other mechanical builds they use a clippard smav 3 being tripped by some sort of pilot valve, that takes the human timing out of the question. I have a zap zx600 that i would like to modernize this way.

[ChoSanJuan]

Brought this up in 2021

https://www.mcarterbrown.com/forum/paintball-news-aa/ask-the-experts/77858-fasor-mechs

While anything is possible, it seems like not without a lot of work.

[SR_matt]

Brought this up in 2021

https://www.mcarterbrown.com/forum/paintball-news-aa/ask-the-experts/77858-fasor-mechs

While anything is possible, it seems like not without a lot of work.

So I take it you didn't try it haha?

I do see some nuggets in there though I will have to try and digest a bit better.

Really I think we just need to get NOVA to figure it out since they have been doing weird stuff forever and would do it rather cost effectively.

[ChoSanJuan]

Yeah, I didn't move forward with it lol

[flyweightnate]

The spring return is what makes it so tricky.

The closer you get to the valve, the harder the spring pushes back, so you can't rely on momentum to get the hammer there the way you can with a sear-tripper. The pressure really needs to be a lot more than the spring force.

An idea would be to vent the ram at the end of travel, quickly. Have it such that, just as the ram gets to the valve pin and opens it, whoosh, all the air escapes the ram piston so the spring can drive it back. But, then you'd need to shut off the ram inlet some distance down the stroke, and have the trigger release reset the air inlet. Otherwise it would just oscillate like crazy across that vent.

It would be pretty easy to make a binary trigger, though. Push from position 1 (closed) to 2 (open) to 3 (closed) quickly, and it would provide a temporary pulse of air; on release it would do the same in reverse.

Some metered volume to push into the ram, then vent at the end of the stroke, is probably the cleanest way to do it. Just not sure it would be very "crisp".

[SR_matt]

The spring return is what makes it so tricky.

The closer you get to the valve, the harder the spring pushes back, so you can't rely on momentum to get the hammer there the way you can with a sear-tripper. The pressure really needs to be a lot more than the spring force.

An idea would be to vent the ram at the end of travel, quickly. Have it such that, just as the ram gets to the valve pin and opens it, whoosh, all the air escapes the ram piston so the spring can drive it back. But, then you'd need to shut off the ram inlet some distance down the stroke, and have the trigger release reset the air inlet. Otherwise it would just oscillate like crazy across that vent.

It would be pretty easy to make a binary trigger, though. Push from position 1 (closed) to 2 (open) to 3 (closed) quickly, and it would provide a temporary pulse of air; on release it would do the same in reverse.

Some metered volume to push into the ram, then vent at the end of the stroke, is probably the cleanest way to do it. Just not sure it would be very "crisp".

oooo thats a good concept, you could likely even harness the air from the ram venting to reset the trigger to possibly give some RT effect, or use it to shut the flow off in a way that requires the trigger resetting to "unlock" it as a way to meter it without any other chambers. The chamber metered concept (which was what I was originally thinking) likely is the simpler option though but at that point I would think you may be able to not even need to vent the ram that way (although it could help reduce cycle time) and just use a QEV.

I sure wish I had access to a mill and lathe, this would be such a fun project.

[Magmoormaster]

RuleOfSines/Peculiar Paintball built a mechanical Tippmann E-bolt, which is a FASOR. Seems like a pretty complicated setup, but it functions.

https://www.youtube.com/watch?v=tquNdpewvbo&t=835s

[RuleOfSines]

RuleOfSines/Peculiar Paintball built a mechanical Tippmann E-bolt, which is a FASOR. Seems like a pretty complicated setup, but it functions.

https://www.youtube.com/watch?v=tquNdpewvbo&t=835s

I've got a simpler design in mind, it works great when the trigger is held, but suffers in the opposite direction. Its possible to short stroke it so to speak, I need a way to ensure every trigger pull always releases a full burst of air even if it is very quickly released.

[SR_matt]

Actually the more I think about this I am thinking all you need to do is have a simple valve system where the trigger pushes a piston back directing air to the ram and then let the ram push the piston back forward at the end of the stroke, you would need something that disconnects the trigger from the rod but that would be pretty easy and could just use the same design concept from the old mechanic Spyder frames with the little spring loaded piece on the trigger that clicked past the sear.

With this I think you would avoid any potential for getting hot shots, a short stroke may be possible but I think that is likely able to be overcome or drastically reduced. then you would just use LPR pressure to adjust the velocity.

Granted if you didn't put a disconnect you may be able to get the RT effect.

[Fubarius]

You know, it might be easier if we reverse the whole operation. Forward On Spring, Air Return. FOSAR. I like the sound of that. So a spring drives the hammer forward into the valve, which releases a burst of air to blow the hammer back....

...wait...

Oh heck, I reinvented the blowback.

Never mind, continue with your discussion.