SpudFiles

Another disadvantage is that you have to be cautious with letting the propane expelled
In closed places. Pulling outdoors is the right thing to do. If used in enclosed spaces,
Let air and not do 50 shots in a row ...

Here's a dangerous thought, what about a premixed chamber of propane and air? The big risk is the thought that the whole main chamber would ignite, but I'm sure some safety measures like a non-return valve would avoid such a possibility.

If you're right. The safety valve would be placed in the larger chamber, regulated to open only a little more pressure than that used to move the plungers. I could use one of these maybe.

jackssmirkingrevenge wrote:Here's a dangerous thought, what about a premixed chamber of propane and air? The big risk is the thought that the whole main chamber would ignite, but I'm sure some safety measures like a non-return valve would avoid such a possibility.

"Dangerous" is an understatement.

jimmy101 wrote:

jackssmirkingrevenge wrote:Here's a dangerous thought, what about a premixed chamber of propane and air? The big risk is the thought that the whole main chamber would ignite, but I'm sure some safety measures like a non-return valve would avoid such a possibility.

"Dangerous" is an understatement.

For this reason I am thinking of using refrigeration gas. One candidate I can get in my city is the R-410A, which is neither toxic nor combustible. I must use a pressure regulator at the outlet of the tank because its pressure is about 16 bar at 25ºC.

I found this wandering on youtube. I think I have to copy!
[youtube][/youtube]

The builder had posted it on the forum http://www.spudfiles.com/combustion-can ... ml#p282194

Sadly the website with the details appears to have been taken down, here's an archived version but unfortunately without the media.

jackssmirkingrevenge wrote:The builder had posted it on the forum http://www.spudfiles.com/combustion-can ... ml#p282194

Sadly the website with the details appears to have been taken down, here's an archived version but unfortunately without the media.

Thank you !

Project update
I have this project to work in this year 2018. I carried out concept tests and everything works correctly.
This system derives from the small autonomous hybrid that I have. I have worked on real information, that I extracted from these two weapons, (I built 2 of them).
The installation is for testing only, and I still need to integrate the ammunition loading system that is already working. Work with low pressure 1.8X - 2X.
In the video you can see how this design works. I insert 6 mm ammunition of air soft to simulate in part, the restriction that will normally have the combustion chamber, and force the valve piston with depressurization to open fully.
It is a solution, of the several that there is, to manufacture a semi-automatic and automatic hybrid weapon as well.
It is time to accelerate the process, and raise the pressure. These two issues were not objective in these first tests. I want it to work only. You can simplify several things of this installation, easily, but I must build everything again, thinking as I said before, in about 8 bar of compression pressure, and accelerate the cycles.
I can hardly put a video of the ammunition loading system .22 working here. It's what I want to add to the whole.
I will also upload a diagram of the general idea, and of the elements that I used. 8)


[youtube][/youtube]

I do not know what I'm doing wrong. I can not get the video image to be seen. If someone can tell me what I'm doing wrong, I'll thank you.

Hey wait a minute, I just watched that, I'm subscribed to your channel

[youtube][/youtube]

That's how it looks better. Thank you farcticox1. How did you make the video like that?

In full editor click the 'youtube' button

[youtube] [/youtube]

paste the Share link inbetween (I spaced it out a bit so it shows) you used the full page link not the Share link

I was using the share link. Thank you

Really really great work! I hope you understand that what you achieved has been a "holy grail" for many users on this forum, the fact that you made it work - especially with limited materials and tools - is truly laudable.

I like the way it's almost "alive", do you plan to incorporate it into a rifle-type launcher?

I have to finish trying the other ideas, which are comlementaries of this that you saw. There are several corrections that I have to make. I realized these things while working with this experiment.
First redesign the piston valve with depressurization, because it lacks exhaust flow.
Second increase the diameter of the hoses in everything that refers to air leaks. I need at least 6mm or 8mm hoses to accelerate the process. Of course, in the operative prototype, they will be metal pipes of at least 8 mm of internal diameter, of esous that diesel engines use in the injector pump.
Third, Redo absolutely everything because I have in mind to work this hybrid with at least 8 -10X. It's not worth work for less,
Fourth, Integrate the components to reduce the volume. This is simple to do but at this stage of development it is not very important.
I have in mind to make a handgun, rifle type, or maybe a small cannon to shoot 10mm steel balls. I have to see why I can not make too much noise here, A while ago I tried to shoot 5X one of these ammunition and the noise increases a lot with the increase in caliber. If I do not consider this, I will go live under the bridge !!
I am finishing the corresponding diagrams to leave it here. When I finish them I upload them because otherwise, the post is incomplete.
I am now working on the ammunition loading system that is now ready to test. I will also upload the corresponding video here.
Actually, by speeding up the process, this can trigger automatically ... Just hold down the ignition. As you can see, everything depends on the speed of the cycles. More pressure, shorter piston travel distances, less mass of the components that move,and larger hose diameters will accelerate this a lot.
This is to play a bit in my workshop in 2018. There is still a lot to improve and develop.
Thank you very much Jack for your comment that motivates me to work more with this, I'm glad you like it.