Spring loaded ball valve design

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
User avatar
Marffy
Specialist 2
Specialist 2
Posts: 258
Joined: Mon Jul 27, 2009 2:03 pm
Location: earth

Wed May 12, 2010 6:48 pm

The main problem with most spring-loaded ball valves (besides the fact that they are ball valves) is the way you have to set them up. I haven't yet seen one with the trigger behind the ball valve. Always in front. Because of which i designed a spring loaded BV with a pulley and i was wondering if you guys think it would have the same performance?
Attachments
Untitled.jpg
Untitled.jpg (22.77 KiB) Viewed 8116 times
"Hard work has a future pay-off. Laziness pays off now."
User avatar
Gun Freak
Lieutenant 5
Lieutenant 5
Posts: 4971
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Been thanked: 7 times

Wed May 12, 2010 7:02 pm

Well the pulley would create more friction, but it should work just about the same.
OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gaderelguitarist
Corporal
Corporal
Posts: 580
Joined: Sat Aug 16, 2008 9:56 pm
Location: Columbia, MD
Contact:

Wed May 12, 2010 8:03 pm

Just make sure your pulley is well lubricated and aligned well. I look forward to seeing this built.

You could put the finished gun on a nice wooden stock and really have a home run.
so many muchness
User avatar
Marffy
Specialist 2
Specialist 2
Posts: 258
Joined: Mon Jul 27, 2009 2:03 pm
Location: earth

Wed May 12, 2010 8:16 pm

Gaderelguitarist wrote: You could put the finished gun on a nice wooden stock and really have a home run.
Already made the stock before i posted :D
"Hard work has a future pay-off. Laziness pays off now."
User avatar
boyntonstu
Sergeant
Sergeant
Posts: 1039
Joined: Sun Jun 28, 2009 8:59 am

Wed May 12, 2010 8:17 pm

User avatar
clemsonguy1125
Sergeant 5
Sergeant 5
Posts: 1485
Joined: Tue Jul 21, 2009 4:00 pm
Location: East Coast

Wed May 12, 2010 8:50 pm

Ive got one just like that, its got a crappy wooden stock and I never considered it worthy of posting, Its accurate and gets 100 yard ranges at 60 psi
That is all.
User avatar
Marffy
Specialist 2
Specialist 2
Posts: 258
Joined: Mon Jul 27, 2009 2:03 pm
Location: earth

Wed May 12, 2010 9:11 pm

boyntonstu wrote:Is this close enough?

http://www.spudfiles.com/forums/a-50-po ... 20987.html
the trigger is still a little more in front of the valve. i want the trigger to be significantly more behind the valve.
"Hard work has a future pay-off. Laziness pays off now."
User avatar
boyntonstu
Sergeant
Sergeant
Posts: 1039
Joined: Sun Jun 28, 2009 8:59 am

Wed May 12, 2010 9:32 pm

Marffy wrote:
boyntonstu wrote:Is this close enough?

http://www.spudfiles.com/forums/a-50-po ... 20987.html
the trigger is still a little more in front of the valve. i want the trigger to be significantly more behind the valve.
This design should allow you to place the trigger anywhere you wish.

Image
User avatar
FighterAce
Specialist 2
Specialist 2
Croatia
Posts: 295
Joined: Fri Oct 23, 2009 1:28 pm
Location: Croatia/Zagreb
Has thanked: 1 time
Been thanked: 4 times
Contact:

Thu May 13, 2010 2:27 am

I made one exactly like that but everything is turned around compared to your sketch. I think theres really not much difference witch way you turn it...

Image

At first it worked very badly because I had a weak spring for this system. When you use a pulley like that you loose a lot of spring energy so I had to step up to a more powerful spring. So if you want to keep performance similar to an inline spring-valve handle design you need to go with a spring with at least double the power.

I could of placed the trigger as far back as I wanted but I tried to make a 1:1 replica and didnt really care how far the trigger will be compared to the valve handle :D
User avatar
chinnerz
Specialist 4
Specialist 4
Posts: 470
Joined: Mon Dec 28, 2009 8:08 am

Thu May 13, 2010 2:58 am

i have seen one before on youtube.... cant seem to find it...
but you are not the first to think of this. just putting it out there
Image
MRR
Specialist 3
Specialist 3
Posts: 361
Joined: Tue Feb 17, 2009 2:29 pm

Thu May 13, 2010 3:56 am

Actually I don't understand the renaissance of ball valve cannons at the moment :roll: . A well made piston cannon is and will be superior to BV cannons big time, especially when you are going multi shot.

However, I do have some experience with ball valves and here are my 2ct.

1. Shorten the lever on the ball valve and use a strong spring to fasten opening time.

2. Put the spring inside a piece of pipe to protect you fingers.

3. Release the screw of the ball valve a little bit and/or lubricate the inside.
User avatar
boyntonstu
Sergeant
Sergeant
Posts: 1039
Joined: Sun Jun 28, 2009 8:59 am

Thu May 13, 2010 6:33 am

MRR wrote:Actually I don't understand the renaissance of ball valve cannons at the moment :roll: . A well made piston cannon is and will be superior to BV cannons big time, especially when you are going multi shot.

However, I do have some experience with ball valves and here are my 2ct.

1. Shorten the lever on the ball valve and use a strong spring to fasten opening time.

2. Put the spring inside a piece of pipe to protect you fingers.

3. Release the screw of the ball valve a little bit and/or lubricate the inside.
1. Shorten the lever on the ball valve and use a strong spring to fasten opening time. Agree. Use a bigger valve to open wider/degree.

2. Put the spring inside a piece of pipe to protect you fingers.

Not needed if spring is forward of your fingers.

Also, addition friction will weaken the spring's force.

3. Release the screw of the ball valve a little bit and/or lubricate the inside.

Do NOT release the handle.

File own a space between the handle and the valve where they meet until there is light between them.

Lubricate, yes.


Best way is to:

remove handle, replace nut.

Chuck a socket that fits the BV nut into a drill (15 mm for my 3/4" valve)

Spin it at the drill press lowest speed/hi torque setting until it feels pretty warm. Cool down, repeat several times.

(insert a wood dowel to hold the ball to loosen the nut.)

Use a fish scale to measure the initial force, mine was about 10 pounds.

It got down to 2 pounds.

Another tip: Close the ball valve to ~80 degrees where it still seals.

Spring does not have to pull that initial 10 degrees.

Pull from the 80* position.

I recommend a $15 ebay 50 pound pistol crossbow as the spring and or the trigger mechanism.

You can also use multiple rubbers each one easy to cock but adding force to the group.

And last, pull on an arc for a constant torque.

Image

If you just pull the handle its like a bicycle pedal your force weakens as your foot pushes down beyond horizontal.

FWIW
MRR
Specialist 3
Specialist 3
Posts: 361
Joined: Tue Feb 17, 2009 2:29 pm

Thu May 13, 2010 8:41 am

2. To put the spring into a pipe makes perfect sense when you use something that can rip the flesh off your bones, no matter in which position the trigger is. The additional friction (if there is any at all) can be neglected.

I've used this spring on a ball valve cannon and to cock it is a challenge of its own.
Image

3. To loosen the screw is absolutely ok with me. If you feel uncomfortable with that then use a drop of Locktight.
User avatar
Technician1002
Captain
Captain
Posts: 5189
Joined: Sat Apr 04, 2009 11:10 am

Thu May 13, 2010 1:15 pm

Another tip: Close the ball valve to ~80 degrees where it still seals.

Spring does not have to pull that initial 10 degrees.
Believe it or not, this is a bad idea. Here is the argument.

2 cars are drag racing. One starts 20 feet behind the starting line and is permitted a rolling start. Neither car can cross the line early. Both cross the start line at the same time. One is traveling 40mph as it crosses. Which car will make the first 40 feet the quickest?

A running start before the valve cracks open is a good thing as the actual time taken to open is shortened once it actually cracks open.

All my valves are using a pre open travel distance for a running start when they do open.
User avatar
Brian the brain
Moderator
Moderator
Netherlands
Posts: 3496
Joined: Mon Dec 05, 2005 2:06 am
Location: Holland
Been thanked: 3 times

Thu May 13, 2010 1:31 pm

Agreed.
In the same lie of thought I prefer small area differencial in a piston valve.
It waits longer to open but when it does more opposing force has left through the pilot.
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
Post Reply