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3" Piston

Posted: Sun Feb 27, 2005 12:04 am
by PCGUY
<div align="center">3 INCH PISTON

Provided By FoxxLord - <a href="http://www.geocities.com/cain333_2000/" ... 3_2000/</a>

Here it is, my version of a 3" piston. It goes in Heavy Barrel, my latest coax golf ball cannon.

It turned out pretty well as you can see with the pictures towards the bottom of the page. Right below is parts list, assembly diagram, and the steps that I used to fabricate it.

The only really specialized parts are the disks I cut from 1/4" sheet PVC. Sheet PVC is probably the most handy stuff in the world, but I suppose any kind of disks would work just fine.

<img src="http://www.spudfiles.com/official_pics/piston.gif">

These are a few pictures of the actual piston itself. Hopefully they will give you a better idea of what it looks like complete.

<img src="http://www.spudfiles.com/official_pics/pstn.jpg">

Side view. You can see the extra set of grooves I cut in it to test what depth and position I liked. All I did was put the bolt in, tightened it, stuck it in a drill press and turned it like a lathe.

That's also the seam of the 3" pipe. I threw some JB weld in it to even the gap, but the 3" shell actually held it's shape perfectly after I dunked it in cold water.

<img src="http://www.spudfiles.com/official_pics/pstnbak.jpg">

Just a bottom view. Those are the vent holes drilled in the 14/" disk.

<img src="http://www.spudfiles.com/official_pics/pstnfrnt.jpg">

A look under the rubber disks where the holes will only pass air one way. I used two disks cut from an inner tube because it's softer than neoprene.

<img src="http://www.spudfiles.com/official_pics/pstntop.jpg">

Finally this is just a fuzzy picture of the top of the piston. The picture was taken before I changed the hardware layout. I used a regular bolt at first but then decided to permanently glue in threaded rod so I wouldn't have to worry about sealing up the bolt.

That's all I have for now. The piston works really great, a lot better than the Pringles can piston I had in the gun before! Have fun.

Provided By FoxxLord - <a href="http://www.geocities.com/cain333_2000/" ... /</a></div>

Posted: Thu Mar 02, 2006 3:29 pm
by pyromanic13
how exactly does this work im haveing alittle trouble figureing it out

Posted: Thu Mar 02, 2006 4:18 pm
by Atlantis
This is not the place to ask this, go to this for a simple animation.
http://www.advancedspuds.com/valve2.htm
Next time look around before asking.

Posted: Thu Mar 02, 2006 6:36 pm
by dragon finder
Hey I had another epiphany why not take a peice of your pvc chamber and use a bit of it as a mold fill it with bondo and when you take it out drill a hole in the center to hold the rubber disc in place using thredded rod, lock nuts, and washers and several other holes around that to equilize tha pressure and fit some O-rings on it, lube it up and you have a durable piston.
(Man I am on a roll with these epiphanys)

Posted: Thu Mar 02, 2006 7:51 pm
by K40T1C
yeah i hade that idea about two weeks ago... exepct min was using plaster of paris... but hey... great minds think alike

Posted: Thu Mar 02, 2006 7:56 pm
by dragon finder
I think plaster of paris will shatter bacouse plaster is priddle(sp) right. But I don't know much about plaster.

Posted: Thu Mar 02, 2006 8:01 pm
by K40T1C
yeah i guess so but its the same basic concept... YAY US!!!

Posted: Thu Mar 02, 2006 8:14 pm
by dragon finder
HOO RAHH :D :P :D :P

Posted: Thu Mar 02, 2006 8:18 pm
by saladtossser
always wondered if a 2" coupling will work instead of a cut up 3" pipe

and dragon finder, search up "operation liquid wood" on here

Posted: Thu Mar 02, 2006 8:23 pm
by Shrimphead
Ya, I'm also wondering if a 2" coupling would work. It's gotta be about the same thickness of 3" pipe if it's pw. Just sand out the stop in the coupler, put a length of 2" pipe in it just a little shorter than the coupler. Then follow the rest of the instructions. Would this work?

Posted: Thu Mar 02, 2006 8:25 pm
by dragon finder
I found it and now I am confused did I do somthing bad?? Because I didn't kick up this old topic pyromanic13 did.

Posted: Thu Mar 02, 2006 8:27 pm
by theregoesthewindow
Saladtosser just meant your random post of
dragon finder wrote:HOO RAHH :D :P :D :P
because it gave nothing to the topic.

Posted: Thu Mar 02, 2006 8:33 pm
by dragon finder
If you/he reads the four posts under my first you/he will under stand why I did it.

Posted: Thu Mar 02, 2006 10:21 pm
by pyromanic13
wow did'nt realise a discussion would ensue but it sounds like its improveing the design ....oh ya and right before I looked at this topic I looked at advancedspuds to see if any thing changed didnt se the new stuff page

Posted: Wed Jul 12, 2006 7:03 pm
by adtchuck
Ok, I see this stuff has been here a while, but, I turner down a coupler before, and it worked pretty good, I had thought about how to make a piston, and this had never evenoccured to me, I will give her a GO, and let you know my results with the couler piston.
Chuck