OS.32F with a 12X4 prop

I stuck a 12.4 prop on my .32.

25% oil, (20% synth 5% castor.

The venturi is the one I use on a .25VF (small) , I'll measure it later.

It reaches 9.000 rpm, and it wants to pull the stand away.

If i use a bigger venturi i figure I'll reach 11,000.

If I trim the prop to 11.5"or 11", I'll have to test it.

Tough little bugger!

Ion

PS

More results tomorrow.

>I stuck a 12.4 prop on my .32.
>
>25% oil, (20% synth 5% castor.
>
>The venturi is the one I use on a .25VF (small) , I'll
>measure it later.
>
>It reaches 9.000 rpm, and it wants to pull the stand away.
>
>If i use a bigger venturi i figure I'll reach 11,000.

And you can fly it at night, because the head will be glowing enough to light the way.

>>I stuck a 12.4 prop on my .32.
>>
>>25% oil, (20% synth 5% castor.
>>
>>The venturi is the one I use on a .25VF (small) , I'll
>>measure it later.
>>
>>It reaches 9.000 rpm, and it wants to pull the stand away.
>>
>>If i use a bigger venturi i figure I'll reach 11,000.
>
> And you can fly it at night, because the head will be
>glowing enough to light the way.
>
> Brett

Gotcha!

I'm having a head made with longer fins...

Iom

ION
I think BRETT was referring too it's way too much load for that engine. I have a re-worked OS-32F from Tom Lay and He removes some of the head fins. The Venturi size should be .250. Hope this helps

Scott (just the facts maam) Riese

Scott,

I know it's too much load.

But a 10 X 4 is too litle for it.
I has to run at 11.500 RPM
Maybe an 11 X 4...

I'll try one tomorrow

Ion (stole your trick) Muniz

>Scott,
>
>I know it's too much load.
>
>But a 10 X 4 is too litle for it.
>I has to run at 11.500 RPM
>Maybe an 11 X 4...
>
>
>I'll try one tomorrow
>
>Ion (stole your trick) Muniz

WHY??? run it at 11,500
Scott(It has a needle if think)Riese

LAST EDITED ON Feb-09-04 AT 01:35 AM (CDT)
 
>Scott,
>
>I know it's too much load.
>
>But a 10 X 4 is too litle for it.
>I has to run at 11.500 RPM
>Maybe an 11 X 4...
>
>
>I'll try one tomorrow
>\

I guess I don't see the problem with 11500*, either, but going from 10 to 12 is probably too big a jump. Plus, all 12-4's are not created equal - a very light load 12-4 (Bolly, etc) may be OK. A 12-4 Zinger or similarly baseball-bat-like prop, no way. From the indications, the 12-4 you are trying probably tends towards the latter, rather than the former. The difference in power between 9000 and 11500 is TREMENDOUS, and a little venturi tweak is not going to get you twice or more HP.

My experience is that these sorts of engines to not like being loaded down, and they do not put out a lot of ponies at low revs. Even if a 10-4 is not very efficient, you can make up for that by having 75% more to begin with!

Add load only until the motor is running in a medium 2-stroke, and the airplane is running the right airspeed.

Brett

* when I was having run problems with my PA40 at the 96 NATs, I ended up launching at 12100 RPM. Sounded like a turbine, but hey, you do what you have to do.

>>Scott,
>>
>>I know it's too much load.
>>
>>But a 10 X 4 is too litle for it.
>>I has to run at 11.500 RPM
>>Maybe an 11 X 4...
>>
>>
>>I'll try one tomorrow
>>\
>
> I guess I don't see the problem with 11500*, either, but
>going from 10 to 12 is probably too big a jump. Plus, all
>12-4's are not created equal - a very light load 12-4
>(Bolly, etc) may be OK. A 12-4 Zinger or similarly
>baseball-bat-like prop, no way. From the indications, the
>12-4 you are trying probably tends towards the latter,
>rather than the former. The difference in power between 9000
>and 11500 is TREMENDOUS, and a little venturi tweak is not
>going to get you twice or more HP.

Brett, you know me better than that!
The 12 X 4 was just for the heck of it. I'd never think of using one. but on a 10 X 4 it still runs kinda fast on some ships.

If i increse the pitch it'll probably go even faster. I'm going to try an 11 X 4, and if it's too much load, a 10.5 X 4.

I'd like it to run at 10 G, but if it ain't loaded enough I'll get that deaded runaway.m And if don;t deliver what I want at 10G I'll gradually increase the revs until I feel it's got all them ponies together.

John Leidle found a good setup at 9 something G's, but I find it'll develop its best at 10. I used it on a 10 X 4 at 12.00, but it's kinda critical, and in a hot summer day it can overheat, pus it was a tad too fast.

> My experience is that these sorts of engines to not
>like being loaded down, and they do not put out a lot of
>ponies at low revs. Even if a 10-4 is not very efficient,
>you can make up for that by having 75% more to begin with!

Exactly, Brett. Even a tiny more load than it likes and it might een take off and fly level PK, but it'll let you down on the first wingover. It must run with a SMALL reserve of power, not so much that it'll runaway, but enough to perk it up when loaded on the climbs.

>Add load only until the motor is running in a medium
>2-stroke, and the airplane is running the right airspeed.
>
> Brett

That's exactly my plan.
>
>* when I was having run problems with my PA40 at the 96
>NATs, I ended up launching at 12100 RPM. Sounded like a
>turbine, but hey, you do what you have to do.

Darn you, Brett, I know you have a truckload of .40VF's.
I can't afford a PA right now, but you sure could sell me one of 'em VFs...

God bless you!

Ion (come'on, you ain't no collector!() muniz

HI
I own a OS .32 and bought a Randy Smith pipe for it I have yet to take it out any tips on setting up a OS .32 on a pipe? I've been told they can be very pipe sensitive what does that mean?
Thanks
Dwayne

I use my very old baffle pistonn os .15 with 9x4 plastic gray Graupner prop, LA .25 with 10x4. Both at almost steady 2 cycling. I never had .32, but I beleive it will work with 11x4, but I do not beleive 12x4. 9000 is too little. Larger ventury will not help. It will help for smaller prop and higher rpm.

>I use my very old baffle pistonn os .15 with 9x4 plastic
>gray Graupner prop, LA .25 with 10x4. Both at almost steady
>2 cycling. I never had .32, but I beleive it will work with
>11x4, but I do not beleive 12x4. 9000 is too little. Larger
>ventury will not help. It will help for smaller prop and
>higher rpm.

WOW!!

Igor, you slick, sibaritic, semantic, Slovak!

It's the first time yu say something a already know!

Either yiou're gettin' dumb ot I'm gettin' smart!

God bless you!

I really do not know how you know I use such props on my old OS ... Rogi told you? It must be that Rogi makes you smart