Search found 25950 matches

by jackssmirkingrevenge
Fri May 28, 2021 10:39 am
Forum: Pneumatic Cannons
Topic: Gluing schrader valve in mini coaxial
Replies: 2
Views: 247

Re: Gluing schrader valve in mini coaxial

Epoxy doesn't really stick well to rubber so you're best off removing it. Before I had a lathe I would strip off as much as I could with a box cutter and then finish off using a hand drill and file.
by jackssmirkingrevenge
Wed May 26, 2021 9:24 am
Forum: General How-To & Discussion
Topic: Counter balanced hammer valve issue
Replies: 10
Views: 538

Re: Counter balanced hammer valve issue

There are some commercially available valves as upgrade parts like the Cothran Powerhouse , I had made an animation of how it functions . That particular valve adds a floating element to regulate the "bleed" and therefore valve reclosing, though I'm not sure how much of a difference it actually make...
by jackssmirkingrevenge
Wed May 26, 2021 8:32 am
Forum: General How-To & Discussion
Topic: Counter balanced hammer valve issue
Replies: 10
Views: 538

Re: Counter balanced hammer valve issue

In my experience of balanced valves it cannon be too unbalanced if you are using a material like delrin to seal.
by jackssmirkingrevenge
Wed May 26, 2021 8:19 am
Forum: Hybrid Cannons
Topic: Any official studies of Hybrid Cannons?
Replies: 8
Views: 965

Re: Any official studies of Hybrid Cannons?

D_Hall wrote:
Sat May 22, 2021 4:46 pm
There is also a DTIC paper out there on Vera... But I'm not going to dig it up.
Do you mean this presentation or was there something more detailed?
by jackssmirkingrevenge
Wed May 26, 2021 8:12 am
Forum: Combustion Cannons
Topic: Potato Howitzer
Replies: 8
Views: 2790

Re: Potato Howitzer

saveitforparts wrote:
Sat May 22, 2021 9:49 am
We tried being somewhat scientific so the last half of the video is graphs and stuff.
Good stuff!
by jackssmirkingrevenge
Wed May 26, 2021 8:10 am
Forum: Off-Topic Hobbies
Topic: Two Italian WW2 helmets found
Replies: 5
Views: 350

Re: Two Italian WW2 helmets found

Nice find! The lack of rim does make it seem like they are paratroop helmets: https://i.imgur.com/hEJdoxC.jpg Worth doing a bit of research as to the exact units involved as to my knowledge it was mostly Alpine troops in this area or operations. Indeed, I hope there is more stuff left on that locati...
by jackssmirkingrevenge
Mon May 17, 2021 8:37 pm
Forum: General How-To & Discussion
Topic: Counter balanced hammer valve issue
Replies: 10
Views: 538

Re: Counter balanced hammer valve issue

There are different configurations for balanced valves, this post should be of interest if you haven't seen it already. Most of them have the opposite problem of not reclosing. The solution for that is the same as the spirit of Hector's suggestion, bleeding air from the transfer port in order to for...
by jackssmirkingrevenge
Mon May 17, 2021 8:30 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2448
Views: 220623

Re: "In the world of spuds today"

Image wasn't showing: https://i.imgur.com/r3MeioB.jpg "22 metre £1.1 million hyper-velocity gas gun. 100 g projectile, which can reach a maximum velocity of 6.5 km/s using 3 kg of gunpowder. Aims to create the conditions required for nuclear fusion." I believe the expression rhymes with "clucking be...
by jackssmirkingrevenge
Thu May 13, 2021 9:30 am
Forum: Pneumatic Cannons
Topic: Issues with the GGDT software
Replies: 5
Views: 528

Re: Issues with the GGDT software

Could someone explain the valve settings? My air cannon uses a 1'' ball valve, but I don't see any options in the settings for that. For a ball valve, select "generic valve" Leave the flow coefficient at 45% Seat diameter would be 1 inch You'll have to estimate the opening time depending on how you...
by jackssmirkingrevenge
Sun May 09, 2021 9:08 am
Forum: BB, Airsoft, and Pellet Guns
Topic: Semiauto Nerf Rival with no moving parts.
Replies: 12
Views: 851

Re: Semiauto Nerf Rival with no moving parts.

I've had this issue with o-ring detents and pellets, the head pops through but then the tail gets stuck on the o-ring.
by jackssmirkingrevenge
Sun May 09, 2021 8:53 am
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2448
Views: 220623

Re: "In the world of spuds today"

Apparently it was a "hot" loaded round, he was very lucky that one of those lugs didn't kill him.
by jackssmirkingrevenge
Sun May 09, 2021 7:32 am
Forum: Pneumatic Cannons
Topic: How to make an Air cannon sound cooler/louder?
Replies: 17
Views: 900

Re: How to make an Air cannon sound cooler/louder?

Do you know where they are bought commercially? I'd like to show people that they have an air deterrent project and they need to increase the noise from the markers. If you search for "airsoft amplifier" on places like eBay or Aliexpress you'll find plenty. Other useful key words include "Sound Hog...
by jackssmirkingrevenge
Fri May 07, 2021 12:05 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: WORKING Simple Semi auto mechanism
Replies: 4
Views: 435

Re: WORKING Simple Semi auto mechanism

For rubber balls a simple breech like farcticox1 made here would do the trick, paintballs would get smashed though.
by jackssmirkingrevenge
Fri May 07, 2021 10:52 am
Forum: Hybrid Cannons
Topic: Xtreme-patator
Replies: 11
Views: 683

Re: Xtreme-patator

hectmarr wrote:
Fri May 07, 2021 10:27 am
wow is supersonic!! :o
I imagine some of your creations also exceed the speed of sound ;) even though your projects focus mostly on function and not maximum performance.
by jackssmirkingrevenge
Fri May 07, 2021 10:47 am
Forum: Pneumatic Cannons
Topic: Whats best valving for pneumatics
Replies: 5
Views: 472

Re: Whats best valving for pneumatics

Would the quickness of releasing the slide valve make any difference on a QEV to the speed of the projectile being launched. Faster piloting means faster valve opening which means better performance, to a point. Here is a virtual launcher modeled in GGDT: https://i.imgur.com/jaMwUuq.png As it is, w...