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My first working piston

Posted: Sun Mar 16, 2008 5:52 am
by Antonio
I finally was able to make this piston type of bbgun work. Its really basic, but does tend to leak out of the barrel sometimes. I was astonished by the power it had, its awesome. I think it has potential, but it doesnt seem to be as efficient as hammer type of airguns. But yeah I guess jack proved that it was a good principle. I tried using a electric solenoid to open the piston but it only worked using a blowgun which kinda disapointed me. I thought I could make it semiauto by using the electro solenoid. Do any of you have a advice to improve this? I will post some pics, prob this weekend.

Posted: Sun Mar 16, 2008 7:29 am
by bluerussetboy
You don't think letting all of the air out of the chamber for one high powered shot is efficient?

I'm looking forward to seeing the pics of this new creation.

Posted: Sun Mar 16, 2008 2:37 pm
by MaxuS the 2nd
Piston looks really heavy, what is it made from, Aluminium?

Posted: Sun Mar 16, 2008 3:48 pm
by Antonio
MaxuS the 2nd wrote:Piston looks really heavy, what is it made from, Aluminium?
Aluminium piping yeah, it is prop 4-8grams. I used the same materials as on my older airguns.
bluerussetboy wrote:You don't think letting all of the air out of the chamber for one high powered shot is efficient?

I'm looking forward to seeing the pics of this new creation.
Here are the pics. It isnt a really fancy creation, but I am happy with this piston as I have no experience with ehm. Well efficiency in my mind is multiple shots on an air tank. But ill c what I can do, bc jack really impressed me with his vids:)

Posted: Sun Mar 16, 2008 4:29 pm
by SpudUke5
Its nice but you got alot of pilot room, but in time you will be making great guns, and JSR would be proud. :)

Posted: Sun Mar 16, 2008 4:53 pm
by Gippeto
Glad you got it working! :)

Is this a breech loader? It looks as though you can loosen the bolt and pull out the barrel. Interesting idea.

Your pilot volume is not too bad, but you may be getting a lot of leakage past your piston, which might be why your solenoid valve did not work.

Welcome to the "World of Pistons" :wink:

Posted: Sun Mar 16, 2008 5:00 pm
by Antonio
LikimysCrotchus5 wrote:Its nice but you got alot of pilot room, but in time you will be making great guns, and JSR would be proud. :)
Hey thnx, could you guys give more specific feedback as I have never worked with these pistons. Like I dont know what u mean by pilot room, I assume the back volume behind the piston. Does this affect the speed of opening or the amount of air that needs to be taken away in order to open the piston? I think using copper tubing there is allot of potential. This piston can be disassembled totally unlike most PVC pistons I have seen, i think this could be of great benefit. I dont know if ppl noticed that I recycled my old valve tubing to use it for this project": Image

edit:
Gippeto wrote:Glad you got it working! :)

Is this a breech loader? It looks as though you can loosen the bolt and pull out the barrel. Interesting idea.

Your pilot volume is not too bad, but you may be getting a lot of leakage past your piston, which might be why your solenoid valve did not work.

Welcome to the "World of Pistons" :wink:
I havent made any breech loader or anything yet. This is a pure prototype but with the materials I intend to use in the future. As I said this piston airgun can be totally disassembled. I used the oring from my previous projects to seal the barrel with the copper pipping. It works nice but the barrel needs to be sanded down a bit as it otherwise wont fit through the oring. I saw on your piston that it had an oring in the middle, i guess this seals it of better for leakage past it. I didnt make this as I was afraid that air wouldnt come to the back of the piston. Actually this whole setup didnt work until I put a round of tape around the piston so that it made a better seal. The problem is that the tape wears off, so yeah I gotta fix this. It would be beautiful to get it working with the solenoid, as it never really had any good use:) Hey thnx for the feedback.

Posted: Sun Mar 16, 2008 5:26 pm
by Counterstriker
Nice job , I can't wait to make mine, Why don't you give it a copper chamber instead of a soda bottle?

Posted: Sun Mar 16, 2008 5:33 pm
by Antonio
Counterstriker wrote:Nice job , I can't wait to make mine, Why don't you give it a copper chamber instead of a soda bottle?
Thnx. Yeah they have amazing power! I used the bottle as I use it on all my airguns. Its better as you can acces more space and parts, as this is a prototype its more handy. I didnt know if it was ganna work so being able to open it again is really nice:) Its also that I dont keep old airguns I reuse parts, so this is the best method.

Posted: Sun Mar 16, 2008 5:33 pm
by Antonio
Counterstriker wrote:Nice job , I can't wait to make mine, Why don't you give it a copper chamber instead of a soda bottle?
Thnx. Yeah they have amazing power! I used the bottle as I use it on all my airguns. Its better as you can acces more space and parts, as this is a prototype its more handy. I didnt know if it was ganna work so being able to open it again is really nice:) Its also that I dont keep old airguns I reuse parts, so this is the best method.

Posted: Sun Mar 16, 2008 6:02 pm
by bluerussetboy
Yes, the pilot volume is the air space behind the piston. The least amount of air you have to release the faster your piston will actuate. With tight fitting pistons and small pilot volumes you really can pilot them with prestas and shrader valves. Even your solenoid valve might pilot it if the pilot volume was small enough.

Nice looking first piston BTW.

Posted: Thu Mar 20, 2008 4:55 am
by ghostman01
looks like a very short barrel, i agree with you statement
Well efficiency in my mind is multiple shots on an air tank.
i have moved from single shot guns like my ones to more efficient ones. probably because i want to make ones specifically for airsoft btw it looks very "your style" lol

Posted: Thu Mar 20, 2008 6:03 pm
by Antonio
bluerussetboy wrote:Yes, the pilot volume is the air space behind the piston. The least amount of air you have to release the faster your piston will actuate. With tight fitting pistons and small pilot volumes you really can pilot them with prestas and shrader valves. Even your solenoid valve might pilot it if the pilot volume was small enough.

Nice looking first piston BTW.
Thnx for the explanation and the respect:)

ajdevi92 wrote:looks like a very short barrel, i agree with you statement
Well efficiency in my mind is multiple shots on an air tank.
i have moved from single shot guns like my ones to more efficient ones. probably because i want to make ones specifically for airsoft btw it looks very "your style" lol
As this is only a prototype I can insert any barrel into this design. Yeah I had the same idea, I wanted to make airsoft guns (homemade) for my bday so I could play with my friends. Too bad that I still dont have a automatic one. Yeah as I said I recycled the parts, and soldering works out great for me (if I have enough gas lol)

Posted: Thu Mar 20, 2008 6:54 pm
by SpudFarm
how big is the piston housing?

Posted: Thu Mar 20, 2008 7:02 pm
by Antonio
spudfarm wrote:how big is the piston housing?
The copper pipes have an inner diameter of 10mm and outer 12mm. I am not sure what the length is. As it is a protoype its not that important.