Atom Jet with applied EVG

[PyroJoe]

Forrest,
Should I use these new values to setup the test?
Thanks, Joe

[woody500]

I was going to ask the same question, I will go ahead and use the new values. Phil.

[WebPilot]

Joe and Phil,

 I would make only one petal, perhaps even with fillets, and make the mount (fake retainer) rectangular and adjustable. As the mount shortens the petal effective length, it will cover the fillets, as you say, but you will have an experimental record of "what's going on" as the length diminishes.



 The above is just a sketch to familiarize me with the 'scale' of the project. You're working with some really small stuff. My initial idea is to

1. make a single petal as above; even with the very small fillets (those depicted are R 0.25 mm). They are there only to 'break' the sharp edge.
2. drill and tap two holes in the valve plate and
3. make a clamping bar with two screw holes and a milled slot, just allowing the petal to slide through it

 You probably have your own ideas along these lines.

[woody500]

Hi lads, this is my set up I can adjust by moving the retainer the hole is slotted one way, using a dti i can measure how much the retainer moves the valve stays in place on a shoulder bolt.

MOV00020.MP4

(1.24 MiB) Downloaded 304 times

The retainer is a pyrotainer with a clamping area diameter of 17.53 concentric with valve mounting hole.

[PyroJoe]

Nice setup Phil,
Admittedly, I'm not the most proficient, but the frequency appeard to be 926 Hz for several seconds. Does anyone else pick up the same? What was the dimension from the valve tip to the retainer contact area? (if it can be measured)
Joe

[WebPilot]

 
 I get 953 Hz for the fundamental. I PM'ed Phil about it last night. He said he will look into it.



(c.t.)

[woody500]

Hi Joe, distance from tip of petal to contact area is 14.24mm I cant measure this but I know it is right from continual measuring and checking of other dimensions. Are you doing a set up as well would be good to cross reference.

[woody500]

Here is the latest sound film with checked and re checked set up, as I said in pm Forrest I spent hours on this making sure everything was right.

MOV00023.MP4

(1.22 MiB) Downloaded 348 times

[WebPilot]

 
 Much cleaner signal, Phil, (compare it to above) but still getting too high of a fundamental. This time it's 921.9 Hz. I've PM'ed you again.



(c.t.)

[PyroJoe]

Phil and Forrest,
Still working on my rig, there may be a way to attach the retainer to a cross slide from a lathe, and hard mount the valve material. This would allow a calibrated advance, also using a dial indicator against the retainer (as Phil did) as a second reference.

If this would work, then the frequency shift could be recorded along with the dial of the slide and the dial indicator. The retainer would have to be loaded against the valve in some manner.
Joe

[woody500]

Hi everyone, here is the latest recording you asked for Forrest, its one petal with no hole underneath it and the two other petals closest are taped down so as to not interfere, this was the best one out of loads.Also included is the two other sounds you asked for.

MOV00029.MP4

(1.11 MiB) Downloaded 295 times

MOV00032.MP4

(1.27 MiB) Downloaded 294 times

MOV00033.MP4

(1.28 MiB) Downloaded 321 times

[woody500]

Hi Joe, nice idea about using a lathe, difficult to set up though good luck hope you sort it.

[PyroJoe]

Ha,
Ingenious, looks like you fellas are a step ahead.
Joe

[Viv]

Very impressive work guys and very interesting

Viv

[WebPilot]

Phil,

Thanks for all of this. You now need to measure your recording system's (in this case, camera) ability to faithfully reproduce the desired frequency range. That's why I asked you earlier if you had any audio equipment. PM me sometime today.