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does this piston look right.

Posted: Wed May 16, 2012 1:24 pm
by 8tonsemi
Its based off of techwizzy's A.K.A Gun freaks.

This is the design I'm going to use. It is 2x.1 1/4 inch pvc end caps. 1x. 5 1/6 inch threaded rod. 1x. Neoprene washer. 2x. 1 1/4 inch Pvc couplings. 2x.o-rings. And assortment of nuts and washers. (sorry for bad glare)

Posted: Wed May 16, 2012 3:05 pm
by jsefcik
Yes that looks fine

But add more rubber on the end that seals on the barrel

And put something to make it airtight around the nuts

Posted: Wed May 16, 2012 3:57 pm
by Gun Freak
Oooh, nice :)

But, Y U NO use stop nuts?

You may find that you need another rubber washer on the face to account for imperfections in the seat, but try it out first. Looks fine, but that doesn't mean anything ;)

Posted: Wed May 16, 2012 4:21 pm
by 8tonsemi
The rod actually got cross threaded so I have to rebuild it.

Posted: Wed May 16, 2012 4:32 pm
by Gun Freak
Go easier on it next time :P

Posted: Wed May 16, 2012 7:50 pm
by mattyzip77
Once you get that bad boy up and running, make sure you constantly check your bumper. I have had this piston smash through the back female adapter and bushing and a few other members as well. Just be careful. A 2 inch rubber sanding drum works well as a piston in this housing as well and its totally adjustable. Good luck.

Posted: Wed May 16, 2012 8:12 pm
by jsefcik
mattyzip77 wrote:Once you get that bad boy up and running, make sure you constantly check your bumper. I have had this piston smash through the back female adapter and bushing and a few other members as well. Just be careful. A 2 inch rubber sanding drum works well as a piston in this housing as well and its totally adjustable. Good luck.
A two inch sanding drum works very well as matty said, they can bust through

My sanding drum piston is alot better,, I only have a small bumper, nd it pumps golf balls!!! Matty knows the one Im talking about

Posted: Wed May 16, 2012 8:25 pm
by mattyzip77
jsefcik wrote:
mattyzip77 wrote:Once you get that bad boy up and running, make sure you constantly check your bumper. I have had this piston smash through the back female adapter and bushing and a few other members as well. Just be careful. A 2 inch rubber sanding drum works well as a piston in this housing as well and its totally adjustable. Good luck.
A two inch dancing drum works very well as matty said, they can bust through

My sanding drum piston is alot better,, I only have a small bumper, nd it pumps golf balls!!! Matty knows the one Im talking about

I have no clue what a "Dancing Drum" is Jesse? :? :? Does it do the macarena when you actuate it??

Posted: Wed May 16, 2012 9:22 pm
by jsefcik
mattyzip77 wrote:
jsefcik wrote:
mattyzip77 wrote:Once you get that bad boy up and running, make sure you constantly check your bumper. I have had this piston smash through the back female adapter and bushing and a few other members as well. Just be careful. A 2 inch rubber sanding drum works well as a piston in this housing as well and its totally adjustable. Good luck.
A two inch dancing drum works very well as matty said, they can bust through

My sanding drum piston is alot better,, I only have a small bumper, nd it pumps golf balls!!! Matty knows the one Im talking about

I have no clue what a "Dancing Drum" is Jesse? :? :? Does it do the macarena when you actuate it??
doesnt say that on mine,

Posted: Thu May 17, 2012 7:09 am
by Mimikool
I don't now what what will you use it for, but the threaded rob looks too thin compared the seat diameter.

I guess this piston will recoil, end shock in the tee or i don't now.

I made a qdv with a 6mm threaded rod and 16mm seat diameter, after some shoots, the rob is completely twisted, and steel washers too.

You piston looks good for the sealing but not very strong.

Sorry if i don't undertsand the problem ^^

Posted: Thu May 17, 2012 8:43 am
by mattyzip77
Nahhh, I disagree with above,^^^ as long ad you have a good bumper you will be fine, I use a tennis ball in mine and its The design Gun Freak uses.

Posted: Thu May 17, 2012 12:32 pm
by Mimikool
Yes, with a good bumper, but after many shoots.. i don't know...

The diameter is large, so the forces are very "strong", with a pneumatical bumper you will certainly no have problem, but there aren't many materials wich could be a good bumper durably.

But if you have experience with that, he would prefer follow you ;) just aninformative theory ^^

Posted: Thu May 17, 2012 9:44 pm
by Gun Freak
Mine have been through hundreds of shots and the only thing that happens is the washer slightly warp. But the rod doesn't bend :)

Posted: Fri May 18, 2012 11:55 am
by 8tonsemi
I'm also thinking of using 1 1/4 inch coupling for the piston. How would I get o ring grooves in it correctly. I only have a drill a hack saw and a dremel. Any ideas

Posted: Fri May 18, 2012 12:02 pm
by mattyzip77
Dont bother, go to Harbor Freight and get a 2 inch sanding drum, it works 100 times better! I have used every piston there is for this housing and its worked the best and you dont gotta mess with o rings or any of that bull shat! However if you must use the coupling theres no need to cut o ring grooves, just get a piece of 1 1/4 pipe and cut the coupling. Do you get what I mean??