Q's: Brauner Design

[Mark]

Here's this site, it's pretty cheap for nice hard blue tempered spring steel, the good stuff. I may sound like a broken record, but you might like to try methanol instead of gasoline, it is more forgiving rich or lean and peppy but the fuel metering jet will need a bit larger diameter if you want to try that.
I think these size jets all use the .006ths thickness of spring steel, so the .010 is probably a bit stiff, almost twice the recommended. Anyway I feel sure you will find your way soon, and it's lots of fun when you hear your jet run.
Sounds like you have plenty of good equipment/tools to get the job done. Anyway, this is a good company to order from, they are fast and cheap for spring steel, often it only takes two days from when you call them toll free.
Mark

http://www.use-enco.com/CGI/INSRIT?PMAKA=406-0008

[pezman]

Tony,

Awesome workmanship!

I stumbled across this guide on making valves, in case it's of any use:
http://www.aardvark.co.nz/pjet/makevalves1.pdf

The etching technique looks cool.

[tony]

thanks for the tips, i've got some spring steel coming now.

found some .01mm *BRASS* shim stock and i tried it for lack
of anything better to do. it only ran if i forced air down the throat.
looked / sounded like a burner more than a jet.

plugged the intake with my hand, opened and closed the orifice with
my fingers (while i still forces 100psi air down the thing) and it went
into a 'fluttering' mode which is what i think i should be hearing.

had to take the fuel nozzle out (the outtermost screwy bit) and hooked
the gas line right to the fuel venturi.

the tailpipe (stainless) started glowing red. cutting the air off stopped
the entire process.

fun while it lasted. now i reek of gasoline.

will wait for the right sized shims to come in.

thanks all.

PS.. most importantly.. I WANT TO MAKE ANOTHER ONE!
found plans for a CHINA jet and also ATOM. the Atom plans
look really nice. recommendations for next PJ?

[larry cottrill]

Tony -

If you're considering the Chinese, you must have some inclination to build a valveless engine. In that case, a much simpler engine than the Chinese is the 'Short Lady' Focused Wave Pulsejet that Steve Bukowski and I have been working on, and have both gotten to run on the first try. Check Steve's build out at
http://www.pulse-jets.com/phpbb2/viewtopic.php?t=1004
and mine at
http://www.pulse-jets.com/phpbb2/viewtopic.php?t=1046

Note that we are still working out a better intake design, but hey - it runs!

You can also check out how earlier on Steve built my super-cheap design, the Elektra I, at the Elektra I Jet Engine Builders Web Log:
http://www.elektra1.blogspot.com/
This is not a high-performance engine by any means, and is big and clunky [about 1 metre long], but it is fast and easy to build, and will cost you almost nothing for materials. You MUST take precautions against breathing fumes while welding, because the parts are galvanized steel. If you want to build one, I can send you an invitation to join as a member to the 'blog.

Anyway, just blowing my own horn a little by offering you a couple of simple valveless alternatives that I've come up with this year.

Good luck!

L Cottrill

[tony]

larry,
those valveless engines look great, and (apparentl) ease with which
they're built looks appealing..

here it comes: where do i get the plans/drawings?

-tony

[steve]

here you go:

[larry cottrill]

Tony -

Be sure to check out how Steve experimented with the fuel feed on his Focused Wave Engine. What he ended up with is better than my original ideas shown on either of the plans, and should work well for both of these engine types.

My plan doesn't show any engine mount lugs for the FWE, but if you want to do them like I did, they are exactly the same pieces that are shown on the Elektra I plans, except you have to bend them inward to weld onto the tailpipe as shown in my WIP photos. You bend them in, then bend the front 1/2" of the top corner back out a little to fit the cone and weld [you can see this on the big closeup photo of the front end assembly of the engine]. Very simple. You cut both lugs out of a 'fence bracket' [from someplace like Lowe's or Menards].

Be sure to read all the Valveless threads that are titled anything like 'Elektra I', 'Short Lady' and 'Focused Wave', etc. There's enough info there for you to build from. If you want to talk more about these, please go to the Valveless Pulsejet Forum and post something there [probably, start up a new thread since yours will be a new build]. Note that we are still discussing the best way to proceed on the intake to the FWE, and there may be some changes in the works - but, that's part of the fun of what you're trying to do!

L Cottrill

[Mark]

dang, i can't get this build fast enough. i'm spending way too many
happy hours in the shop.

got the nozzles done and they're installed... this thing is starting to
look mean. part of me will feel bad when it all turns black and lights
on fire. but i guess thats the whole point.

tried to make the valve leaf today.. the 'flower' ... all i can get my
hands on is 0.010" spring steel. is that gonna be too rigid??

cut it out with a cad print and a dremel tool. thought i did a good job, but
nothing lined up right. will try again tomorrow.

do the petals actually have to be rounded at the ends? what if i just
cut radial slits??

-tony

I tend to have bad luck if the reeds don't overlap equally, that is, if you have a certain overhang at the tips, you should have near that on the sides. You shouldn't have too much more than you need to seal the port either, a little extra is fine, but excessive overhang is bad news I think.
Mark