7 replies to this topic

[Beomagi]

I started my first homemade(s). I'm a recent Nerfer (wife's awesome Valentines day gift) - Mostly to relieve work stress by plinking down empty water bottles. I started getting some with the intention of modding - a retaliator, a hammershot and cycloneshot but recently I've been looking at making a spring and air powered blaster.

 

I'm looking forward to finishing up my spring powered blaster, but holy hell air powered blasters are amazeballs. The only thing is my pump was a cheap bike pump that seems to be geared for high pressure - so it actually hit's over 200psi.

While it can hit pressures that high, it takes forever to pump to standard​ levels, and high pressure is rather pointless. I'll probably look for a way to limit this to 30-40 PSI instead. Using a QEV on my prototype.

 

This is from ~85 PSI - nope, not running that much in the house...

 

Does anyone know of a good High Volume​ bike pump? Rather than pumping 20 times to hit my pressure goal I'd rather pump 5 or 6 times...

 

Also what are good ways some of you attach the base of the pump to your frame? I can see this taking a lot of stress.

[jwasko]

Hey there, welcome!

 

You may want to check out Ice Nine's QEV blaster, detailed here and here.

 

He used a Schwinn floor pump; he might show up and provide a model or a ling to where you can buy one.

 

He also was lucky to get someone to make a 3D-printed shell, but you might be able to get by with some large diameter hose clamps.

 

Care to share a full picture of your blaster so far?

 

Edit: Picture of someone who made a "shell" out of sheet plastic

Edited by jwasko, 13 March 2017 - 07:14 PM.

[KaneTheMediocre]

For VERY high volume / low pressure (10-15 psi) you can use any 1.25" PVC pipe sized blaster piston that includes a check valve mechanism as a pump.  With a wee bit of creativity you can make a good compromise using 1" pipe (I used a mcmaster skirt seal when I did it), which will get you close to 20 psi (Unmeasured, but fired at full power from a stock big blast which has an OPRV close to 20 PSI i think).  I bet if you made a pump in 3/4" pipe you could get to the 30-40 range with a little bit less pumping than a typical bike pump, but I've only used 1.25" and 1" pipes before.

This vid is of an odd thing that uses a 1.25" PVC pipe for a pump, but it is a bit of an extreme case.

Edited by KaneTheMediocre, 13 March 2017 - 07:37 PM.

[shmmee]

Ball pumps often have a bigger diameter and the 6 to 10" pumps are still small enough to integrate onto most shells. For higher volume lower pressure the key thing to watch for is pump diameter. The bigger the diameter the more volume it will move - at the cost of pressure.

[shandsgator8]

Ball pumps often have a bigger diameter and the 6 to 10" pumps are still small enough to integrate onto most shells. For higher volume lower pressure the key thing to watch for is pump diameter. The bigger the diameter the more volume it will move - at the cost of pressure.

 

And correspondingly, effort. My Schwinn floor pump takes a lot of muscle to use compared to pumps with a much narrower diameter.

[Beomagi]

Well, here's the blaster currently. Realized I can remove the pump hose. Figure I can strengthen the point where it screws in by building up there with metal epoxy or something.

 

 

 

Thanks for the links guys. I can use the shell idea with another design. I'm already getting parts for another

This is turning into any of my other hobbies where I'm spending as much time building/modding as playing with whatever it is I wanted to play with.

Edited by Beomagi, 16 March 2017 - 03:38 PM.

[jwasko]

Is that a 3-way or a 4-way valve that you are using there? Are you directing the vented air from the 3 (or 4?) way valve to the barrel?

[Beomagi]

It's a 3 way (which of course is not really necessary), and yes, the little extra air is redirected to the barrel (check valve to prevent blowback). I believe it would make more of a difference with a smaller tank. Figured if I can fire a dart on that air alone, I may as well use it too. I know it's not making much of a difference. Just a little peace of mind.