19 replies to this topic

[nat]

Are Hornet and Big Salvo's blast chambers The same on The Inside Except The big Salvo ones are bigger?

Edited by nat, 16 August 2008 - 11:40 AM.

[CaptainSlug]

Yes.

[nat]

Great! My Plan will work then. Another question are all blast chambers the same?

[imaseoulman]

NO!

Dump Valve Blasters: SuperMaxx Line and AirTech Line. The tanks are all pretty much the same, but the trigger mech varies slightly. Titan, Big Blast, Blast Bazooka, Mega Missile Blaster and a plethora of others. The dump valve means you're actually pulling (via a firing pin attached to the trigger) the valve back (which is pressed and sealed against the front/barrel opening of the air tank). A solid design and lasts a long time. Also, the higher the pressure and the larger the dump valve opening, the harder it shoots and the harder it is to pull back the trigger.

"Blast Chamber" Blasters (as they've come to be called) or Back Pressure Valves: Big Salvo, Hornet, Blast Fire, Triple Fire, and a few others. These work on back pressure and can all use the same trigger system. As long as the trigger allows air to flow back away from the blast chambers they will fire. No matter how big the tank or high the pressure, it's not difficult to pull/push the trigger, but the design isn't as durable as and more prone to leaks than Dump Valve Blasters. Also, Lightning Blitz, Secret Shot 2, and a few others. These get their own category, because while they work on back pressure, their trigger systems are not inner-changeable. The reason for this is that the air does comes in one place with a check valve in the tank and the firing valve (back pressure valve) is in a different spot. The SplitFire gets its own category because there isn't much like it in the foam world. I'm not exactly sure how the trigger allows back pressure, but it does (anybody ever disected or seen into a SplitFire before? Just curious.)

Those two categories cover the majority of blast chambers in NERF blasters. If anybody can think of other types, let me know. It would be good to compile all these things in one place.

[nat]

Ok, I'm planning on replacing hornet blast chambers with big salvo ones. But I don't want to buy two Big Salvos so could a just make bigger ones?

[doubleshot]

NO!

Dump Valve Blasters: SuperMaxx Line and AirTech Line. The tanks are all pretty much the same, but the trigger mech varies slightly. Titan, Big Blast, Blast Bazooka, Mega Missile Blaster and a plethora of others. The dump valve means you're actually pulling (via a firing pin attached to the trigger) the valve back (which is pressed and sealed against the front/barrel opening of the air tank). A solid design and lasts a long time. Also, the higher the pressure and the larger the dump valve opening, the harder it shoots and the harder it is to pull back the trigger.

"Blast Chamber" Blasters (as they've come to be called) or Back Pressure Valves: Big Salvo, Hornet, Blast Fire, Triple Fire, and a few others. These work on back pressure and can all use the same trigger system. As long as the trigger allows air to flow back away from the blast chambers they will fire. No matter how big the tank or high the pressure, it's not difficult to pull/push the trigger, but the design isn't as durable as and more prone to leaks than Dump Valve Blasters. Also, Lightning Blitz, Secret Shot 2, and a few others. These get their own category, because while they work on back pressure, their trigger systems are not inner-changeable. The reason for this is that the air does comes in one place with a check valve in the tank and the firing valve (back pressure valve) is in a different spot. The SplitFire gets its own category because there isn't much like it in the foam world. I'm not exactly sure how the trigger allows back pressure, but it does (anybody ever disected or seen into a SplitFire before? Just curious.)

Those two categories cover the majority of blast chambers in NERF blasters. If anybody can think of other types, let me know. It would be good to compile all these things in one place.

Thank you very much, I was actually going to make a topic to ask this today. The smdtg's valves fall into this category aswell. On another note, were there any guns that used multiple dump valves? Likewise, were there any guns that used single back pressure valves? I see no real advantage in using a single back pressure, but many in using multiple dump valves.

Edited by doubleshot, 16 August 2008 - 09:25 AM.

[imaseoulman]

The National Geographic is sort of a hybrid, as far as those categorizations go.

Its valve is of the back pressure type, such that chamber pressure throws it open quickly, but it is held closed by a mechanical block, instead of by back pressure in another chamber. The trigger knocks the block out of the way, allowing chamber pressure to throw the valve open. When the trigger is released (and the pressure has dropped), the trigger spring pushes the block back into place.

Hmm...I'm becoming more interested in these things all the time. How hard is the trigger pull on these things?

But I don't want to buy two Big Salvos so could a just make bigger ones?

I'm not sure what you're asking...but you do get four big salvo chambers per gun. Are you asking if you can make bigger blast chambers...you could, but I don't know how much benefit it would be. I don't if the flow rate would be great enough to take advantage of more air.

Thank you very much, I was actually going to make a topic to ask this today. The smdtg's valves fall into this category aswell. On another note, were there any guns that used multiple dump valves? Likewise, were there any guns that used single back pressure valves? I see no real advantage in using a single back pressure, but many in using multiple dump valves.

Secret Shot 2 and Lightning Blitz both have a single back pressure valve. I don't know of any blasters with multiple dump valves (Arachnophobia II not included). It gets pretty complicated to have multiple dump valves with a single trigger. I've played with some designs, but before I got into it too heavily, I came up with the Marvelous Salvo, and in my opinion, that precludes the need for multiple dump valves. Necessity is the mother of invention, and I no longer feel the need for multiple dump valves. And as far as advantage for single back pressure, I'm not sure if they have a faster flow rate, but they seem to attain better ranges.

Edited by imaseoulman, 16 August 2008 - 12:25 PM.

[nat]

Are you asking if you can make bigger blast chambers

Thats exactly what I'm asking. But I don't know how the insides work so could someone please tell me.

[imaseoulman]

See if this helps:

In the first phase (A) air coming into the blaster pushes the stopper forward, sealing off the barrel end. Air continues to flow in and compress ( B ). When the trigger is actuated, air is allowed to flow back out (usually the trigger opens a valve somewhere) and the stopper is sucked back © which opens the other end of the blast chamber and the air then rushes out through the barrel. Hope that made sense.

Now, for expanding this, yes you could do a tank expansion, but as I mentioned earlier, I don't know if the flow rate is great enough to allow for more air to get through quickly enough to create any significant increase in power. You can try it and experiment and let us know. Personally, I think the Big Salvo blast chambers have enough power already.

Edit: I had to keep changing the spacing on the ( B ) because those blasted smilies kept showing up!

Edited by imaseoulman, 16 August 2008 - 05:04 PM.

[nat]

I want don't increase the size a BS chamber I want to replace Hornet chambers with BS chambers or just make completely new ones,or expand The Hornet chambers. But that Diagram really helped.

Edited by nat, 16 August 2008 - 05:27 PM.

[nat]

If I cut a pencil eraser sized hole in a Hornet blast chamber and glued a small Pvc tank on It would that increase the pressure build up in it. Sorta like above, I used imaseoulman's picture and edited it a little so you could get an idea. Yeah I saw oodalumps's Awesome maagstrike mod Ad that gave me this idea. I thought if He can do It to a piston I could probably do it to a blast chamber.

Sorry for The small picture

Edited by nat, 16 August 2008 - 09:02 PM.

[AssassinNF]

If I cut a pencil eraser sized hole in a Hornet blast chamber and glued a small Pvc tank on It would that increase the pressure build up in it. Sorta like above, I used imaseoulman's picture and edited it a little so you could get an idea. Yeah I saw oodalumps's Awesome maagstrike mod Ad that gave me this idea. I thought if He can do It to a piston I could probably do it to a blast chamber.

Sorry for The small picture

I don't know much about blast chambers, but I do know that if that did work, you would definitely have to make sure those tank extensions were glued on DAMN good.

[nat]

I haven't done a barrel replacement on my hornet yet. I plan on cutting away slots In the original shell to make room for the new additions. So, Next time I go to Lowes I'll get supplies and start working on this thing. I will most likely do a write-up If It goes well. Thanks everyone for your help.

[imaseoulman]

As long as you can get a good seal, it should work out just fine, but you want to make the whole as large as possible. The smaller the hole, the slower the air gets into the barrel. I'd say pencil eraser size hole is the minimum size for it to be at all effective, and a little bigger wouldn't hurt if you can get it to seal well. Using pvc tee couplers is an easy way to get a good seal.

[nat]

I have another question, Whats best for securing two things together. It has to be super strong and airtight? I was was thinking JB weld two part epoxy or is there anything else that is stronger?

[nat]

Can PVC pipe and the plastic Nerf guns are made of be solvent welded together?

Edited by nat, 19 August 2008 - 10:22 AM.

[imaseoulman]

Can PVC pipe and the plastic Nerf guns are made of be solvent welded together?

Not usually. Sometimes it works, but not usually.

[Draconis]

If I remember correctly, most of the material used for Nerf parts is ABS, and should be able to be solvent welded adequately with PVC/CPVC and ABS pipe. Some nerf stuff feels like High Density Polystyrene, though.

[nat]

Oops, never mind I found my answer.

Edited by nat, 19 August 2008 - 01:55 PM.

[Langley]

In regard to the splitfire questions, I think the splitfire uses two dump-valves. The trigger is mechanically connected to two pins which individually fire the valves. I imagine that the valves have their own individual check valves at their connection to the pump so that the air doesn't backflow from valve2 to valve1 when you fire the first shot out of valve1. Now the valves may not use the 'dump valve' style of mechanism, they may be more like a zero valve on the inside or some other design, but I don't think they are of the blastfire/hornet style because they are independent of each other in terms of the trigger mechanism.