Arruda

Michael:
Unfortunately I have no records of the RPM I got  (this was 3 years ago), but as far as I remember it wasn’t much different than the RPM I used to get with the APC 3 blade prop (15.75 x 13).
I hit a tree with my plane and since then the engine is stored for a future use.
I think you need at least 12 in of pitch to make this Mustang fly.
Arruda

andi3142001

Hi Michael,

I am glad that you finally managed to put things together. Yes once assembled the whole thing is sturdy and tracking of the blades on my exemplar is perfect.
However, I do not have any experience with props that have more than 2 blades, and so its hard to tell which pitch will work. I agree with your doubt that an 8 inch pitch is too small, and also that a smaller diameter would work better. Blades only are not too expensive.

I would suggest a standard 2 blade prop for the maiden flight to save nerves. Maybe its possible to make some taxi tests with 4blades thereafter to assess acceleration etc.


regards
Andi

andi3142001

One more thing concerning the pitch gauge: As far as I remember there are 2 possibilities (different angles) to attach the gauge. What I did to find out which way is correct is to set the blades to about 0 by eyeballing, to assure the gauge is attached from the correct side.

regards
Andi

Michael211

My Feedback: (1)

You cannot set the blades to 0 pitch (at least not on this 4 blade hub!). 6 degrees pitch is where the stops are (and the lowest possible setting on the guage coinidentally). I made sure the blades were at the lowest pitch possible, then once I'd found the "sweet spot" where this guage will clip on to a blade I clipped it on and stuck the pitch pointer rod into the hole in the hub and it read 6, the lowest number on the guage. At that point I figured I was using the guage correctly. As I turn the adjustment bolt in (clockwise) the pitch pointer rod moves up the guage to higher numbers. Ergo, I think I'm using it correctly.

I realize the blades are just a faction of the cost of the hub. It's just that now I have to order another set of 4 blades and wait 2 weeks or so before I can try them. Ughhhhh! I had hoped the engine could swing these 16.6" diameter blades but I guess it can't. Looks neat though. Bet a 120SP would be able to swing 'em (but add too much weight to a 60 sized airframe, IMHO).

I may test run it again 1st and try leaning out the needle 5 or 6 clicks for 20 seconds and see what the engine does... if I lean it too much it should die, then I'd know where the way too lean point is! I wonder if there's a way to tell by engine temp if it's running too lean or not, and if so what's the temp range I should shoot for to keep from harming the engine?

As it ran out of fuel yesterday it sounded a lot smoother and more powerful for those last 10 seconds or so, making me wonder if I'm still running too rich... also I noticed a droplet of raw fuel collected in the air intake of the carb, which seemed odd again making me wonder if I'm still running it too rich.

Thanks ya'll!

- Michael

andi3142001

Yes, I agree with your description.



I dont know the engines temperature, but I do know that temperature depends very much on where you measure it. So its not easy to get repeatable values.

Well thats funny. Maybe tweaking the needles helps a bit.
I always set needles with the model pointing skywards a few degrees.


regards
Andi

Avaiojet

Michael,

I've been following your Thread. Juice's thread also.

I did take a look at Vario Prop's website. Somewhat confusing as far as what you need for different engines setup.

I thought that hub was larger than 1/8 scale?

Do you have measurements on that?

Charles

Michael211

My Feedback: (1)

I only have the 4-blade hub, and it'll be hidden inside a P51 spinner so as not to be seen so it's scaleness is irrelevant to me as long as it fits and does the job. I don't know anything about the 3 blade hub, if I get a Top Flite Corsair ARF later this year (presuming my Mustang project turns out well) then I may get Vario's 3-blade hub for that plane.

- Michael

Avaiojet

I've been sending emails for two days and I get no replies?

Please, what's his correct email for Vario Prop?

Charles

Michael211

My Feedback: (1)

It has been a holiday weekend you know this right Charles? Not everybody works thru the Easter holiday.

I advise patience.

- Michael

Avaiojet

Michael,

Nice looking props!

Did you paint them black or do they come that way?

Charles

Michael211

My Feedback: (1)

They are made of a black material, Charles. I did nothing to them. They don't seem to be plastic either, I'm not sure what they're made of seems like some kind of graphite or carbon material. I still have to order a smaller diameter set so I can proceed on this project... I'm working on recovering the Mustang fuselage in chrome monocote and black trim (to match the real Mustang known as Quicksilver). [>:]

- Michael

andi3142001

Hi,

did you try the prop already?

regards
Andi

Michael211

My Feedback: (1)

No, been too busy with work no time to play lately. [&o]

- Michael

Jafa

Michael211, anything new to report.  I was thinking of getting a RCV 90SP and Vario 12c setup for a Nitro planes P51 (basically a clone of a H9).  Todd