RE: 8.8X9.75 @ 19,300+ !  
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RE: 8.8X9.75 @ 19,300+ ! - 4/28/2008 9:40:04 PM   
SpeedBoy



Posts: 135
Joined: 11/8/2007
From: Monterrey, MEXICO
Status: offline
quote:

ORIGINAL: idigrc2

I've gotten my Y.S 45 up to 18,880 with a 8.75x8nn on 40% with a nitro pipe.


Nice ship idigrc2 , I'm very curious how fast is your airplane with that set-up ???

freakingfast :sorry to turn aside a little your tread

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RE: 8.8X9.75 @ 19,300+ ! - 4/28/2008 10:27:05 PM   
airraptor


 

Posts: 210
Joined: 1/26/2004
From: fairfield, CA, USA
Status: offline 		K2R is the best stuff out there for removing oil from wood.

do you have telemetry in the plane to see if its really unloading that much. i do remember some test done in flight on many different types of planes and the engines didnt unload as much as they sounded. most high pitched props are somewhat stalled on the ground then load back up in flight and that was the reason for the lack of rpm increase. most were in the area of 3-500 rpm.

if you have an engine that peaks at 25,000 rpm and you have it loaded to 20,000 with a low pitch it might make it up to 25,000 again but i dont think your 9+ inch pitch will. it would be nice to know if you have the equipment to measure it.

(in reply to SpeedBoy)
       Post #: 27

RE: 8.8X9.75 @ 19,300+ ! - 4/29/2008 1:47:33 AM   
freakingfast


 

Posts: 704
Joined: 1/3/2005
From: mather, CA, USA
Status: online 		Thanks for the K2R info guys.

I don't know what the RPM's will do, but I figure it's safer to start out with a lot of pitch than have it let go because of too much speed in flight. I had a YS 45 throw a blade of a 9X9 sport prop at speed and it sounded like the world was coming to an end and I don't want a repeat, I woun't get that lucky again.

I will be testing several props in the air. Hopefuly I can have it Video'ed and learn speed & RPM from that. Till than it's ears, eyeballs and SWAG method (Scientific Wild A$$ Guess).

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When in doubt, give it full power. The smaller
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       Post #: 28

RE: 8.8X9.75 @ 19,300+ ! - 4/29/2008 1:41:23 PM   
RocketRob



Posts: 538
Joined: 12/27/2002
From: San Francisco, CA, USA
Status: online 		Getting along with my project - Thanks FreakingFast!!

Finished my $1,000 motormount
Hogged from a 2 1/2" 2024 T3 barstock.

Going in a RVRacing Miss Ashley Q40

and yes, thanks for the K2R tip!

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       Post #: 29

RE: 8.8X9.75 @ 19,300+ ! - 4/30/2008 5:49:15 AM   
freakingfast


 

Posts: 704
Joined: 1/3/2005
From: mather, CA, USA
Status: online 		Nice machine work! The hard part is over, mounting these DFs are a pain, but it sure looks like you got it handled

_____________________________

When in doubt, give it full power. The smaller
pieces fit easier in the bag! Revver Bro #201

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       Post #: 30

RE: 8.8X9.75 @ 19,300+ ! - 4/30/2008 6:08:05 AM   
Razor-RCU



Posts: 5282
Joined: 3/21/2002
From: Ramona, CA, USA
Status: offline 		Oh my gosh that is beautiful! NICE!!

Keep us posted!


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       Post #: 31

RE: 8.8X9.75 @ 19,300+ ! - 4/30/2008 1:49:36 PM   
RocketRob



Posts: 538
Joined: 12/27/2002
From: San Francisco, CA, USA
Status: online 		Hey Thanks guys.
It was my first mill project under the tutorage of a buddy (his machines).
There are commercially available mounts which could be used on this engine - but none that would fit within Miss Ashley
The raw stock was $42/ft - bought 2'.

Freakin, who has this new prop? is it carbon?
Checked the Tower site and no listing

< Message edited by RocketRob -- 4/30/2008 1:51:46 PM >

(in reply to Razor-RCU)
       Post #: 32

RE: 8.8X9.75 @ 19,300+ ! - 5/1/2008 1:04:29 AM   
freakingfast


 

Posts: 704
Joined: 1/3/2005
From: mather, CA, USA
Status: online 		The prop is not realy new...to me it is
It's an APC 8.8 X 9.75 but I didn't see it on their list. I did find it here:
http://www.supertrc.com/details.asp?ProdID=27&category=2
You may be better off with the carbon props, That Miss Ashley is very slick& clean, so clean it may go so fast as to throw a blade on a pylon prop so be careful to keep any non carbon Pylon prop under 25,500 in the air. If you could get there, the pitch speed for that would be 235mph. A carbon 7.4X 8.25 at 30,000 rpm has a pitch speed of 234mph. I know it does not mean the plane will go near that speed, it's just fun to see the numbers.

I have no idea if that pylon prop is any good, it's not very popular, than again not many are stuffing them on a 46 DF engine. Only one way to find out. Lately I’ve been wiped out from work so it's been hard to get back in to the project. The weekends are where I get things done.

Metal has gotten crazy expensive. I work in a very large machine shop in 128,000 square foot facility, about the size of two Costco’s. The amount of material we consume a day is mind boggling, mainly 7075 T-6 aluminum, 4340 HT steel and OFHC Copper. Think tonnage. Big thick non-ferrous plate is getting hard to come by (China is sucking up everything). We place orders over a year in advance on some things just to make sure we don’t run out.

< Message edited by freakingfast -- 5/1/2008 1:05:44 AM >

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When in doubt, give it full power. The smaller
pieces fit easier in the bag! Revver Bro #201

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       Post #: 33

RE: 8.8X9.75 @ 19,300+ ! - 5/1/2008 1:22:59 AM   
idigrc2


 

Posts: 10
Joined: 9/23/2007
From: Anderson, CA, USA
Status: offline 		It's bumping 150, It's not a true scat cat the airfoil has been changed to a thinner wing and the retracts barley fit

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       Post #: 34

RE: 8.8X9.75 @ 19,300+ ! - 5/1/2008 3:18:59 PM   
airraptor


 

Posts: 210
Joined: 1/26/2004
From: fairfield, CA, USA
Status: offline 		7075 and 4340 have never been cheap try high quality Ti. I have 10,000 in Ti on my quad and it isnt very much. IE Ti connecting rod 550.00 piston pin is 145.00 the piston alone is over 2300.00 which i dont have.

(in reply to idigrc2)
       Post #: 35

RE: 8.8X9.75 @ 19,300+ ! - 5/1/2008 3:50:33 PM   
cncswiss1


 

Posts: 190
Joined: 7/15/2004
From: Indianapolis, IN, USA
Status: offline 		I make medical implants for a living, Ti is getting expensive as well, and stainless is going thru the roof right with it. we consume ~ 200-800 lbs of Ti (mostly 6-4 eli) a day @ $50-$80 per lb it gets salty fast!

(in reply to airraptor)
       Post #: 36

RE: 8.8X9.75 @ 19,300+ ! - 5/2/2008 12:05:14 AM   
freakingfast


 

Posts: 704
Joined: 1/3/2005
From: mather, CA, USA
Status: online
quote:

ORIGINAL: airraptor

7075 and 4340 have never been cheap try high quality Ti. I have 10,000 in Ti on my quad and it isnt very much. IE Ti connecting rod 550.00 piston pin is 145.00 the piston alone is over 2300.00 which i dont have.


There's a fortune in Ti in your town(Fairfield), but you can't get at it. At Tavis AFB, 25 years ago when big jet engines (C5A) would let-go in the test cell or otherwise badly dammaged They would simply haul them over to the open pits and burry them. I dont know that they do with trashed engines now, but I bet they don't do that any more.

< Message edited by freakingfast -- 5/2/2008 12:12:43 AM >

_____________________________

When in doubt, give it full power. The smaller
pieces fit easier in the bag! Revver Bro #201

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       Post #: 37

RE: 8.8X9.75 @ 19,300+ ! - 5/9/2008 5:02:09 AM   
lfinney


 

Posts: 9
Joined: 2/19/2008
From: kuna, ID, USA
Status: offline 		the K&B 7.5 if i remember correctly uses the same header as the os vf motors, a simple call to MAC"s products will set you right

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       Post #: 38

RE: 8.8X9.75 @ 19,300+ ! - 5/12/2008 1:23:09 AM   
freakingfast


 

Posts: 704
Joined: 1/3/2005
From: mather, CA, USA
Status: online 		LET'S ROCK !"AL Bundy"



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_____________________________

When in doubt, give it full power. The smaller
pieces fit easier in the bag! Revver Bro #201