Search found 1090 matches

by rp181
Mon Sep 19, 2011 9:57 pm
Forum: Combustion Cannons
Topic: Hypervelocity Advanced* Combustion - WARTLv1
Replies: 64
Views: 12518

Nice job, decent efficiencies too. Where did you get your capacitors?
Your chamber support looks a bit excessive to me. Is this just for sealing?
by rp181
Tue Jan 18, 2011 8:22 am
Forum: Off-Topic Hobbies
Topic: Navy Railgun....
Replies: 21
Views: 1985

Im late here,but: Navy railgun's have a quite long rail life. A smaller 12MJ navy railgun I saw regularly fired 10+ shots in one set of rails, they used steel liners. I don't know technical specs, but the targets were 6 1" thick steel plates spaced about half a inch in a vacuum chamber. It would pie...
by rp181
Mon Oct 18, 2010 7:06 pm
Forum: Off-Topic Hobbies
Topic: What Adhesive, Epoxy Fails
Replies: 27
Views: 1898

they do sell marine epoxy/putty.
by rp181
Mon Oct 18, 2010 7:05 pm
Forum: SpudFiles Discussion
Topic: legality stuff... kinda
Replies: 13
Views: 1350

Whats that DYI? :P


don't worry bout it.
by rp181
Tue Sep 21, 2010 10:29 pm
Forum: Ammo & Parts
Topic: drill press tips
Replies: 24
Views: 2880

spring loaded punches are great. Don't have one? A clamp, a nail, and a hammer works too. make a dent, this way the drill bit doesn't slip. Clamp the pipe, and drill away. Or option two, Bore a block of wood with the pipe OD. Stick the pipe in, and drill through the wood and all. No matter how you d...
by rp181
Tue Sep 14, 2010 7:58 pm
Forum: Miniature Guns
Topic: ETAv2.1 High Velocity Launcher
Replies: 56
Views: 17430

Check out this concept:
http://www.coilgun.info/mark5/home.htm

May not work with that high voltage, but it could still be better.
by rp181
Sat Sep 11, 2010 9:23 pm
Forum: Miniature Guns
Topic: ETAv2.1 High Velocity Launcher
Replies: 56
Views: 17430

lyctics are never very good for this kind of stuff, especially at 400v.

Make sure that 60v isn't from ringing, put a protection diode on there.

DYI: I would, but I am way too busy on the helicopter UAV (funded by the railgun :p).
by rp181
Thu Sep 09, 2010 9:38 pm
Forum: Off-Topic Hobbies
Topic: Future Alternatives
Replies: 18
Views: 2334

The microwave band is regulated, especially to control the possibility of getting too close to the 2.5ghz band.

Co2 laser tubes are large, optics expensive, require cooling, and an RF power source. Lot of work for something large and with minimal power. Almost as bad as a railgun :roll:
by rp181
Thu Sep 09, 2010 9:34 pm
Forum: Miniature Guns
Topic: ETAv2.1 High Velocity Launcher
Replies: 56
Views: 17430

Ever think about ceramic?
Take a look at Macor, great stuff.

Oh ya, its expensive...

I read somewhere about multi-stepping the process. Use part of the energy to get everything vaporized, than dump the rest of the energy through the steam.
by rp181
Wed Sep 08, 2010 7:36 am
Forum: Miniature Guns
Topic: ETAv2.1 High Velocity Launcher
Replies: 56
Views: 17430

Keep in mind PTFE easily crushes, count on that being replaced frequently, so It may be better to go with dimensions that you can buy stock.
by rp181
Fri Sep 03, 2010 11:44 pm
Forum: Miniature Guns
Topic: ETAv2.1 High Velocity Launcher
Replies: 56
Views: 17430

I was not very good with documentation :) I did indeed finish it, and had some projectiles made. I shot it primarily at steel. I couldn't do much due to my location and other issues, just an occasional shot. I do however think it was caused by your description of Larda's ETG, that would play nicely ...
by rp181
Fri Sep 03, 2010 3:46 pm
Forum: Miniature Guns
Topic: ETAv2.1 High Velocity Launcher
Replies: 56
Views: 17430

Nice. I noticed you had some different capacitors. Information on them? I did not think an impact flash was a major thing, I had gotten a couple with the railgun (though that was 12kJ). Ile try to find the video (hard drive failed two times since then...) Looking forward to more progress. EDIT: Inst...
by rp181
Wed Jul 14, 2010 7:02 pm
Forum: Hybrid Cannons
Topic: Using PTFE or other flouropolymers as a barrel material
Replies: 16
Views: 1335

PTFE is soft, and probably will split. I could bend a 1/8" thick piece any way I wanted. a PTFE liner is good though, great [lack of] friction.
by rp181
Mon May 24, 2010 7:32 pm
Forum: General How-To & Discussion
Topic: Spudding Preference Survey
Replies: 27
Views: 1686

1.What kind of new (simple) applications could the community benefit most from? Select Two. -Adiabatic compression calculator -Speed of sound calculator (for any gas or mixture of gases and any temperature, within reason. -Universal fueling calculator (including several fuel/oxidizer and buffer gas ...
by rp181
Fri May 21, 2010 3:41 pm
Forum: General How-To & Discussion
Topic: Casio EX FS-10 1000 fps camera today $99.99 SHIPPED!
Replies: 9
Views: 1629

Beware there is a issue in the low price camera market where sellers sell OEM cameras. They don't have firmware, and want more money to put the firmware on.