Yes the problem was I was trying to turn the material too far from where it was supported so it was bowing and causing chatter. I got this fixed though and turned my piston as well as my o-ring grooves. To make my o-rings fit I stretched the 1" od rings over a piece if 3/4" PVC and heated it very ...

Stock may not be perfectly straight and I will resharpen my tools. Thanks for the help

Now I'm having trouble turning down my round stock on the wood lathe. It starts to chatter and makes the surface very rough. I can't seem to get it to cut smooth and I'm not sure why....

Ok I'm waiting for my Hdpe so when it Arrives I will turn my piston and see what I can get to fit. I have 1" and 1-1/16" o rings so hopefully one of those will work with stretching and/or cutting and re glueing.

Yeah I'm thinking I may have to order from mcmaster. I don't want to pay 5 bucks shipping for a couple cents of o-rings though.

I'm using 1" nominal PVC pipe for the valve body of my QDV cannon. I want to make a floating o-ring piston. The ID of 1" PVC is 1.029". At my local hardware store I can only find 1" and 1-1/16" (1.0625") o-rings which are a tad to small and a tad too large. I guess I need 1-1/32" o-rings (1.03125 ...

Gun Freak wrote:You don't have to machine the piston housing...
Shown with rubber cap piston. May be hard to understand. Ask for clearification

Could you clarify the piston construction? The piston has a lot of colors and components that I'm not sure what they are

If you have a drill press, you can make a piston housing.

He's talking about a piston housing that is fully contained in the Tee itself without any fittings to lengthen it.

Ok I understand. I'm not too interested in machining a piston housing though unless it is necessary for a more complicated ...

I've always wanted to build a compact piston valve, i.e. one without the female adapter behind the tee. Maybe you could do one in 4"? Then make a semi auto beer can loader :lol:

Could you describe this a little more?

And also, I don't think I'm up to machining a housing out of a massive piece ...

urgle the danish cow: How is the yarn attached to to the nail? Whenever I try to do this the yarn just flies off of the nail.

And about the ice ammo, I've done it before. It works but not that great. Still fun to do every once in awhile though since it shatters into nothing when shot at a tree or ...

Everything you're asking of us has been done... Its called the Pneumatic Cannon Showcase :wink:

It's not that I'm too lazy to design a cannon. It's not that at all. I've designed and built many of my own creations through countless research and planning.

The point of this thread is for people to ...

So I have a bit of time on my hands and want to make another coax piston gun. So, I'm gonna leave it up to everyone on the forum to come up with some good ideas for me And what you want to see. If you have a great design that you want made but don't have the time then here's your chance. This cannon ...

Are you experienced with piston valves? I would recommend building a coax piston valve. They're so powerful And simple to build. Also great first piston valve project. If it was possible to easily incorporate changeable barrels into a coax then it would be the best kind of cannon in my opinion.

But ...

If you're still looking for 2.5" fittings, try to look up a Local plumbing supply place. If you can't find them there then order from flexpvc.com. They have great prices and a massive selection. If you manage to need something they don't have (i did) then email them and they will probably have it ...

My design is airtight enough for me to use. Im sure ita not perfect but there is definately no noticable or drastic power loss. Hope you all like my pinkish/purplish 1.5" sdr 21 also It was the only color available to me