Search found 128 matches

by Dave_G
Tue Dec 12, 2006 5:40 am
Forum: Valveless pulsejet forum
Topic: TP180-18 starting to take shape!!
Replies: 57
Views: 19035

re: TP180-18 starting to take shape!!

re: the Stun gun...just so you know: I've used them a couple of times to start pulsejets for convenience sake, but they have a couple of drawbacks: [1] The spark rate is slow, about 2 per sec. Makes starting a little harder. [2] If you fire them continuously for more than about five seconds at a tim...
by Dave_G
Tue Dec 12, 2006 5:17 am
Forum: Valveless pulsejet forum
Topic: TP180-18 starting to take shape!!
Replies: 57
Views: 19035

Re: re: TP180-18 starting to take shape!!

I think we are going to have to start buying the propane tanks for forklifts... dont know if they can be filled at a regular fill station. That's all I use anymore, and yes, you can get them filled at any of the regular filling stations. I don't recommend this to anyone, but before I had mine fille...
by Dave_G
Tue Dec 12, 2006 3:44 am
Forum: Valveless pulsejet forum
Topic: Can't get 'em to run.
Replies: 17
Views: 6190

re: Can't get 'em to run.

First, I am not familiar with the Lockwood calculator you mention (“Lockwood-Hiller puls-jet calulator" ver 2.0 by Marten Klein from 2004â€
by Dave_G
Mon Dec 11, 2006 5:38 pm
Forum: Valveless pulsejet forum
Topic: Can't get 'em to run.
Replies: 17
Views: 6190

Re: Can't get 'em to run.

My twin lockwood set-up just won't go for me. I'm stuck. Any ideas how to coax it into running, or did I produce a dud design? A lack of intake flares will not keep your engines from running. I've run many engines w/o intakes, because the flare itself was removable for adjustability. They will run,...
by Dave_G
Fri Dec 08, 2006 8:34 pm
Forum: Tools and Construction
Topic: Simpl-Jector(TM) Fuel Tube Ready To Test
Replies: 13
Views: 6587

re: Simpl-Jector(TM) Fuel Tube Ready To Test

Larry, One other thought...you don't have to weld these in at all. You can swage them in place using a number of different methods. If you have a lathe chuck (3, 4 or 6 jaw), you can easily make some swaging tools using soft-jaws with some threaded-in ball-nose or dog-point setscrews. If your chuck ...
by Dave_G
Fri Dec 08, 2006 8:21 pm
Forum: Tools and Construction
Topic: Simpl-Jector(TM) Fuel Tube Ready To Test
Replies: 13
Views: 6587

re: Simpl-Jector(TM) Fuel Tube Ready To Test

Larry, Did you check the heads of your fasteners for runout? In my industry it is common to sometimes encounter a batch of Flat-head socket screws that have a runout of up to 0.020" in the #10-32 size. The heads are similar in profile to your drywall screws, and are made using similar technology. Ge...
by Dave_G
Sun Dec 03, 2006 12:54 am
Forum: Pressure jet forum
Topic: Pulseramjet
Replies: 42
Views: 26181

Re: Pulseramjet

[quote="leo"]Read trough this post Dave maybe its helpful?.[quote]

Leo: Thanks!

I was not aware of that thread.

I can see after reading just the first post that it will probably explain a lot. I will read it in full.

Thanks again,

Dave
by Dave_G
Sat Dec 02, 2006 11:02 pm
Forum: Pressure jet forum
Topic: Pulseramjet
Replies: 42
Views: 26181

Re: Pulseramjet

leo wrote:...Still can’t find a patent of it...
It reminds me of this one...wonder what's different?
by Dave_G
Tue Nov 14, 2006 7:58 pm
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

Re: R1 Update

Have you tried throttling down through the range it doesn't want to throttle up in? No, but I agree with Mike; You've got an excellent idea there. During Saturday's testing I was doing a lot of throttling back and forth...just kinda running it without paying a lot of attention to what I was doing. ...
by Dave_G
Tue Nov 14, 2006 6:54 pm
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

re: R1 Update

Lots of good food for thought there, Larry. It also occurs to me that it's probably not a good idea to let the thrust stand do 'Wheelies' at the higher power levels, since Force(measured) = Force(actual) X cos Theta, although since the stand is only tipping up about 15 degrees I figure this accounts...
by Dave_G
Tue Nov 14, 2006 7:23 am
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

re: R1 Mess

Thanks Larry, Mark and Mike for the kind words. I'm incredibly depressed; the last thing I wanted to do here was make spurious posts. I appreciate your kind words. Yes, Mark, a half ton of material is a lot to go through, and I've yet to make a dint. Something about this whole episode is really both...
by Dave_G
Tue Nov 14, 2006 1:43 am
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

Re:DAVID G. IS WRONG

I'M WRONG. Completely, totally, 100% full-of-sh*t WRONG . The engine IS NOT producing 38 lbs of thrust. Despite getting readings of 38 lbs three times in a row Saturday until my tank froze, those readings were in error. Today, after filming the spring scale (which has a max reading hold) during the ...
by Dave_G
Mon Nov 13, 2006 5:49 pm
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

Re: re: R1 Update

...The total volume or how "big" a pulsejet is should be a factor in judging it...Mark I agree completely. When I speak of thrust density I'm referring to, in mathematical terms, thrust-specific volume or volume-specific thrust . Pounds thrust per unit volume, or volume per unit thrust, respectivel...
by Dave_G
Mon Nov 13, 2006 5:48 am
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

re: R1 Update

Well-articulated post, Mike. Thanks. Of course all engines preheat to some degree, but the injector is not forcibly entraining air, and the engine itself is definitely self-aspirated. What I suspect you're asking is, "does the injected fuel stream add momentum, prior to combustion, to the longitudin...
by Dave_G
Sun Nov 12, 2006 8:13 pm
Forum: Valveless pulsejet forum
Topic: R1 Update
Replies: 22
Views: 7551

re: R1 Update

I don't have a problem with that...after all, as Dr. Carl Sagan was fond of saying, "extraordinary claims require extraordinary proof". Besides, I've been able to duplicate the effort to the point that I'm comfortable with the result. As I said here [http://www.pulse-jets.com/phpbb2/viewtopic.php?p=...