Recent content by axi0m

It will be a single event. Thank you for bringing that to my attention. I wonder which allows me to provide the highest kinetic energy to the projectile, the load resistance that provides the greatest power or the load resistance that provides the greatest efficiency?

The objective of the experiment is to propel a projectile via pressurization. It seems that water is very effective at these types of things, hence its use in steam locomotives and nuclear power plants for converting heat to work. Being that it turns to gas at a lower temperature than the...

Q_Goest, thanks for the graph. I gather from what you are saying that it is often acceptable for the hoop stress to exceed the yield strength of the material for a thick-walled tube, given that the central and outer regions of the tube wall experience far less stress. My ignorance of the subject...

If one were to take a powerful source of electricity, such as a bank of high-voltage electrolytic capacitors, and short the source across a thin length of metal wire, the wire would "vaporize." My question, is what is actually happening to this wire? If it were a very thin strand of aluminum...

Minger, thanks for your input. Here is where I collected some of the data for the 440C stainless steel: http://www.matweb.com/search/DataSheet.aspx?MatGUID=850c5024f8d844af8ef95afab1a08792&ckck=1 There is also the following information via a description at McMaster.com: "Ideal for use...

Q_Goest, you've been an incredible help here, as you were to me in the past in another thread. One of the links you provided to me was apparently a calculator that provides the additional stresses involved with a thick walled tube. I'm now looking at stainless steel type 440C, which has a...

Would this be correct? P = 2st/((d-2t)SF) where, P = max. working pressure (psig) s = material strength (psi) t = wall thickness (in) d = outside diameter (in) SF = safety factor (in general 1.5 to 10) So, with a safety factor of 2, P = 2(42,000)(0.5)/((1.5-1.0)2.0) P = 42,000 PSI Anyone...

Hello, I'm looking to experiment with an Electrothermal-Chemical (ETC) system of accelerating a projectile. Basically, it will involve using energetic materials and large amounts of electrical power to create very high pressures inside of a tube in a very short amount of time, behind the...

Here's a quick visual I threw together (misspelling included) that shows the idea I currently have to make this work. It involves a brass barrel with the solenoid coil wrapped around it. This is all encased in a brass tank made of a larger brass tube with donut shaped circles brazed onto its...

I'm constructing a pulsed solenoidal accelerator (coilgun) and am looking to boost efficiency by supercooling the copper wire in the coil. I'm also getting a quote for a high-temperature superconductor film to use in place of the copper wire. In either case, I will need submerge the coil in...

What would the resistor from pin 1 to pin 2 be needed for? And what did you use to calculate those resistor values? Are the NAND symbols the logical representations of transistors? Or are they some other physical device?

Thanks for your response, Bob S. The simple switch I was talking about would consist of slightly more than touching a wire to a battery. It would probably involve an industrial momentary push-to-close switch. I'm fairly familiar with the NE555 timer (not with programming one however), but I'm...

I have a puck-style SCR with a cathode, anode and gate. I'm planning on using it to dump two series capacitors (450v + 450v) into a coil for a "coilgun" project. I understand that the SCR is triggered when a circuit is completed through the gate and anode using, for example, a battery and a...

"Amorphous Ferromagnetic Metallic Alloys" Hello all, In a project in which I'm looking to endeavor, I have a need for a material with high magnetic permeability and high electrical resistivity. In beginning my research, I came across this in Wikipedia: "One can also make amorphous...

Pardon the terrible representation, but here is the general wiring scheme. And yes, they are all identical pairs, except for the two inner-most rails which I've enlarged to help decrease the current density on the sliding contact surfaces where the armature projectile will travel. As for power...