11 replies to this topic

[ompa]

Ok, now I've heard that expandind the airtank on an sm5k is useless, but I just wanted to ask what kind of an increase in range I should be expecting. I haven't tested mine yet because the stupid head of the valve pin keeps falling off, so I have to cut it open again, replace the spring, and make sure the head is on so it won't fall off. Here's a picture of what I have so far, I used a pvc coupler and alot of epoxy. Do any of you think it should be possible to get 150' off this thing? Also, I have 2 sm5k's, which is in part why I am doing this- as an experiment. I know there is already another topic in this already, but I had pictures and the other post really didn't seem to have any information pertaining to what I had to ask.





The cpvc is there because I broke off the little thing that the hose hooked up to on accident... that manages to seal the connection between the pump and the air chamber.

~ompa

[Black Wrath]

Well it looks good. I just wonder how the valve pin works. When I cut my spare SM5k tank open, the pin had a definite length that remained in the tank. The little hook on the end of the pin that slides through that green piece that covers the valve should keep it over the hole. I don't know how it's not doing that for you... maybe it's because of the length on the pin inside the tank.

Now, I couldn't tell you what range increase you would get. I would expect a LOWER pressure, and more air. I think the air would bleed out of the tank, and there wouldn't be very much pressure. Not to mention... you'll be pumping that thing up for about 30 seconds.

[cxwq]

It should increase range a little. Basically, the stock 5k is already nearing the limit of what a reasonably weighted stefan is capable of. My homemade has an enormous air tank and faster release than the 5k but I can't get over 20-30' more range than my 5k before the darts start spinning out. Adding weight to the darts increases the range but in a less than linear fashion.

So, in short, you should be able to get 150' but it will take heavily weighted very high quality darts or your accuracy will go to hell. You'll also find that those kinds of velocities drastically shorten the useful life span of your stefans.

[ompa]

Xx the valve pin works, at least for me anyways. And Cx, is that 150 flat? That would be really nice... Also, a strong spring inside the air chamber should fix any leaks it might have. Also, I'll make special darts for it- just as you recommended Cx, to get those types of ranges and good accuracy. I just wanted to know if I can actually have 150ft flat with this thing.

~ompa

[xedice]

We need aerodynamic stefans. Hot glue tips just don't cut it for aerodynamics and more weight could help also. Invent a new, heavy, aerodynamic stefan to make good use of all that power in your sm5k.

[ompa]

Yes sir! Lol I'll get on it this weekend- or when I should get my expanded airtank up and running. We'll see what I come up with- it's going to take alot of experimenting... but if I come up with anything abnormally good, I'll post it here.

~ompa

[Ice Nine]

We need aerodynamic stefans. Hot glue tips just don't cut it for aerodynamics and more weight could help also. Invent a new, heavy, aerodynamic stefan to make good use of all that power in your sm5k.

Hells yeah. Shape it like a teardrop, it'll be so aerodynamic you can't believe it.

Trust me. I did an experiment with all different kinds of shapes in a wind tunnel.

[ompa]

You mean the hot glue tip? If it really does work that well, I'll try to make them, and make an easy way to make them.

~ompa

[ompa]

Eh, I know I'm double posting, but I think I finished the airtank... Think because I just fixed the last leak that I could detect, so I hope it works. When I tested pumping 10 times really fast then shooting, it got some nice ranges, about 140-150 from guestimating.



That's right, 4 tie wraps. No less than 4 damn tie wraps would seal that stupid part...

Anyways, just finished the whole thing up, here's the entire thing.



And while I'm taking pictures, here's a pair of monkeys.



~ompa

Edited by ompa, 14 June 2004 - 10:24 AM.

[nosferatu]

Nice Job. Some measued ranges would be nice, but it sounds like a great mod. Any more on the new stefan shape would also be great. Keep up the good work. I would also like to say that that is a very nice pair of monkeys.

[reversedracula]

WTB: monkeys. NIB not necessary. Preferably unmodded but will accept damn dirty apes. PM me to make an offer.

[ompa]

Lol anyways... I tested it with 1/4 steel shot stefans, I don't really seem to have a problem with spin-outs or anything, oddly enough. I've found some cone-shaped pieces of plastic I've considrered using, but anything I can think of at the moment would kill something (or someone) if used. I'm actually thinking if I can melt the tip from one of those cone-shaped earplugs it just might work, although it's highly unlikely.

~ompa