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Squishy

Member Since 10 Sep 2007
Offline Last Active Nov 10 2009 12:10 PM

Topics I've Started

Nerfbots

18 May 2008 - 03:11 PM

http://www.ottawarob....org/nerf.shtml
Check it out. Some at3ks and RF20s. Kinda awesome, but old: 2004.

Anyone Else Think This Is Legit?

22 February 2008 - 07:57 AM

I call BS.
LINK REMOVED

EDIT: My apologies. I didn't remember that 'un.

Hasbro Sale

25 January 2008 - 08:10 PM

Only thing really worth looking at is the spidey DTG set:
http://www.hasbrotoy...rc=GENEMHT21205

An Internal Fit Spring For The Recon

16 January 2008 - 11:16 PM

Allright, so I can't really spare it right now, but the Ertl Rapid Fire shotgun's stock spring is a perfect fit diameter wise for the Recon. Will put it in there temporarily tommorow to get ranges.

General Fluid Dynamics Applications

29 December 2007 - 11:06 PM

So I have had a couple people ask me about how we can apply some basic principles of fluid dynamics to nerfing. I have mostly copied and pasted a PM that I thought might help anyone looking to mod or make homemades.

Firstly, avoid any abrupt changes in diameter (any sharp edges at all). A reasonable slope results in much less pressure loss.(at least 3-1 ratio of run to diameter increase) Just take sharp edges and make them smooth, and 10 diameters in length eliminates nearly all turbulence (and thus increases efficiency) of flow. Nerf is an inexact science. But for fluid dynamic applications, I say this:

No abrupt changes in diameter if possible, obstructions are not actually horrible if they obstruct less than 20%, and grids are better than a 20% solid blockage.

Make sure your barrel length volume (volume after the plunger to the end of the barrel) is at about half the volume of the plunger. Longer means less pressure, shorter means expanding gasses are wasted. Exception for Air powered, as they have a much faster expansion coefficient and thus don't need as long as a barrel.

Holes are bad, but we knew this already.

Any change in diameter is desired in this order when possible:
1. Very smooth change in diameter, no edges.
2. sloped change in diameter(change in diamter starts small, peaks near the middle, then goes back to small)
3. Smoothed edge, but abrupt change in diameter.
4. Abrupt change in diameter with sharp edges, like the straw mod. would have said something but it would have been a necro.
5. abrupt change in diameter with a lip, like so(flow from left to right):
______
.....__|___
.....______
_____|

Keep in mind these are general rules and sometimes things like the straw mod increase ranges depending on the properties of the dart and the delivery method of air pressure.

If you have anyone questions I will to the best of my ability answer them.