The Mr.Plow PPP Wannabe

[drac]

Yes. Smaller chmabers equal less pumping time, larger ones mean more pumping and less PSI, the most Ive ever gotten it with a foot pump is about 125, so it's a relatively small chamber.

[julz]

well wih my chamber, about 85 cubic inches i can only get up to 60 psi, then i cannot get any further. any ideas?

[drac]

Ahh, there's the thing. My chamber is only 13 cubic inches, plus i work out (narcissim at its greatest) so it isn't hard to pump it up, untill my arms get tired. If you made it smaller that would make it easier to pump up. Plus, it might help if the bike pump cylinder is well oiled. A dry seal can really decrease how much air you can pump in., Try squirting some DW40 on the rod when you pump it(that came out wrong), it helps. I did that to my bike pump which was my dads from 30 years ago and it works like a charm.

[julz]

...on the rod when you pump it(that came out wrong)

hehe
any way, turns out i bought a dodgey pump. it broke today so i swapped it for a hand pump that get up to 100psi in about 30 goes. man, my mate and i were shooting aat 40psi before we returned the pump and we thought it was awesome but S.H.I.T!! it is good now it sounds like a gun it so fre.akin.g loud now and it managed to shoot a spud 100m verctically up in the air. now i just have to add a silencer and laser sight .
thanks Drac,
---Julz

[drac]

Glad to hear that it works. 100 meters vertical huh? I can barely get that with 125 on mine with a small dowel bit. That's good. Is the silencer going to be just for looks, because it really wont help to make a pneumatic quiter.

[julz]

well i supppose it may not have been 100m. my mate and i reckon it got there but it may have been only 70-80 or something like that. i did add a silencer that i made, just holes, wrapped tightly with ols fabric and then duct tape. this takes away the loud crack that used to be with it and now it is just a muffled bang. a bit like a car door slamming hard. laser is not far off, just for kicks then a gb barrel and aemi auto!
---Julz
ps. you guys here at Spudfiles are great! thanks for all the help!

[drac]

Glad to help. I like the semi auto idea. How do you plan on making it? A tee with bolt action or something like that?

[julz]

atm i have no idea. i guess i'll look around and . AAAAHH! brainwave!

what about multiple smaller chambers, say five, arranged in an easy to handle shape, with each one feeding into the same barrel through an individual valve(solenoid). then a breech loading clip like that on the peacemaker, then five seperate buttons that each open a seperate solenoid, allowing one shot, clip load, 2nd shot, clip load etc. how about it? this owuld be expensive but still i would love the idea of a semi auto cannon with five shots per clip.
damn! i have to save up now
what do u reckon bout that?
--Julz

edit. here is a crappy pic

[drac]

What I would suggest is having a large chamber filled through a ball valve. It gives better flow than a tire valve. ONe valve is good enough and save money. For the breech loader (from the looks of it) will be gravity fed? Or will you use something similar to a bolt? Sorry for asking two questions, I'm just slow at understanding things.
The multiple chamber design sounds cool, but I still think that one chamber would be a bit more efficient.

[julz]

the breech loading wouls have a spring at the top, pushing down the ammo.
sorry, i dont understans the other question. the reason i had 3 chambers is because each one would be worth one shot, if i had one big chamber i would only get one shot, then have to pump it again.

see the True-Semi thread.
---Julz

[drac]

Oh I get it. But three chambers would be veru cumbersome. Maybe making a stand for it would help you aim it. As for the big chamber, I see. What I though was that the valve would stop when you let go of the blowgun or got your hand of the switch, and leave some air in the chamber.

[julz]

oh ok. but you would have still have had to pump again cos the pressure would drop more and more as you took more shots. i hope to begin production as soon as i get more money, about 2-3 months.
---Julz

[tatorassassinator]

[quote="drac"]

I can't use sprinkler valve because they are not available in my area.


Order on off the internet! I had a ball valve on my cannon and it launched pvc rockets a quarter mile and i switched to a sprinkler valve and now it shoots Almost a half mile. They are well worth the buy.

[drac]

To be honest, I don't like ordering online. Besides, I live in the city so the power offered by a ball valve is perfectly fine for me.