Extreme Speed Prop Planes Discuss the need for speed with fast prop planes (Screamin Demon, Diamond Dust, Shrikes or any REAL sound breakin'''' plane)

Can any one suggest a good prop

Reply

Old 01-28-2007, 03:25 PM
  #1  
nitro junky
Member
Thread Starter
My Feedback: (3)
 
nitro junky's Avatar
 
Join Date: Aug 2005
Location: canastota, NY
Posts: 78
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Can any one suggest a good prop

This will be my fastest plane to date. I was looking for some thing that would just blow evey one else away, at the field where I fly. The top speed at our field last year was 127mph with a dago red. [:'(]

I used a pcm receiver with HS-645mg servos. I decided to used carbenfiber for the control rods. I ordered a OS .46 VX-DF that should be here on Wednesday. I'm not sure what prop to use yet. Can any one suggest a good starting point or a good 20%-50% fuel?
Attached Thumbnails Click image for larger version

Name:	Bz79476.jpg
Views:	4
Size:	78.7 KB
ID:	608491   Click image for larger version

Name:	Gb88232.jpg
Views:	4
Size:	75.3 KB
ID:	608492   Click image for larger version

Name:	Lq38407.jpg
Views:	7
Size:	74.6 KB
ID:	608493   Click image for larger version

Name:	Ga77741.jpg
Views:	5
Size:	96.4 KB
ID:	608494  
nitro junky is offline  
Reply With Quote
Old 01-28-2007, 04:14 PM
  #2  
Rudeboy
 
Rudeboy's Avatar
 
Join Date: Dec 2002
Location: Kortessem, BELGIUM
Posts: 3,508
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: New DD

A 7.4x8 APC "carbon" prop would be a good place to start.
Rudeboy is offline  
Reply With Quote
Old 01-28-2007, 07:46 PM
  #3  
MustangAce
My Feedback: (3)
 
MustangAce's Avatar
 
Join Date: Aug 2003
Location: Old Hickory, TN
Posts: 1,027
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: New DD

what engine and prop was on dago??
MustangAce is offline  
Reply With Quote
Old 01-28-2007, 08:12 PM
  #4  
proptop
My Feedback: (8)
 
proptop's Avatar
 
Join Date: Oct 2002
Location: Rome, NY
Posts: 7,022
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

Hey man, whaddoyamean???[:'(]



The Dago Red he's talking about is mine...
Modified Webra .50 with Ultra Thrust muffler and a 10 X 8 APC using 15% Powermaster and an O.S. #8 plug...
It'll turn just under 14,000 on the ground, and it unloads pretty good in the air...

There have been a few aerodynamic mods done to the airframe as well

(I'm working on something a little faster myself for this year...)
proptop is offline  
Reply With Quote
Old 01-28-2007, 08:26 PM
  #5  
MustangAce
My Feedback: (3)
 
MustangAce's Avatar
 
Join Date: Aug 2003
Location: Old Hickory, TN
Posts: 1,027
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

Thinking of a Webra .55 on the same plane.
MustangAce is offline  
Reply With Quote
Old 01-28-2007, 10:19 PM
  #6  
freakingfast
Senior Member
My Feedback: (3)
 
Join Date: Jan 2005
Location: Mather, CA
Posts: 2,222
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

Nice job! I just wish you got the engine before you finished it.
The rear intake and the engine’s power adds some extra work in the engine mounting area. I doubled the ply and used some carbon fiber in the front area. The 46 DF engine is a bit heavy so you need to move or add height to the rear. I put the batteries aft of the rear most spar, yup….between the vertical stabs. That way I didn’t have to add none functioning weight (to me a sin). The area under the fuel tank and batteries are reinforced on the inside with a layer of light weight glass cloth that laps up the ribs and bulkheads than piece of 1/16” ply epoxied on top of the glass. This was done so that if you pull a vary hard high speed turn you won’t throw the batteries through the 1/16 balsa bottom!
Note; if you have it all balanced correctly the plane should balance on the high point of the main spars when placed on a table.
I like to run high speed high torque servos like Hitech HS-5995 TG or JR 8411, they won’t stall or slow with high wind forces. The delta just BAM! changes directions.

You need a good pipe and header. Mac’s pipes and headers are what I use. The #1050 Quiet pipe, #1250 Muffled and the 1150 tuned (noisy) I have all tried and all work well!
To my biggest surprise the quiet pipe rendered the most speed, at least measured on the ground. The best average pipe setting was 9 ½” from center of piston to the large diameter on the pipe. Cutting this ¼” shorter may let the engine stage even higher in the air at the cost of smooth transition, so try this later on if you dare. The highest speed measured was 24,500 RPM (on ground) spinning a APC carbon 7.4X 8.25 on Power Master 30%Heli fuel. OS #8 plug. I tried 15% and RPM dropped to 23K and I tried Wild cat 45% and it dropped to 23K, I think the compression is too high for it. Run with 15% or 30%, it’s plenty fast. You have three header choices’, strait, 15% and fuse top.
The fuse top could help clear the fuel tank however the header length is so short that you need to cut both header and pipe. I made a custom low profile fuel tank that fits in the between the main ribs. I made two small aluminum blocks that allow me to rotate the carb so the needle can clear the mounting rails with out too much cutting. A prop adapter nut and washer are needed and can be purchased from Tru-turn. A good Idea is to buid a test stand for break-in and testing. Note center of fuel tank is centered with carb.

If it were me, I would fly this plane with a good 46 engine or at the most a Webra 55/ red Jett muffler with APC 9X10 and build a clipped wing version for the OS 46 DF engine later.

I hope this Helps
Karl
Attached Thumbnails Click image for larger version

Name:	Nl30024.jpg
Views:	7
Size:	89.1 KB
ID:	608909   Click image for larger version

Name:	Ie98330.jpg
Views:	10
Size:	64.9 KB
ID:	608910  
freakingfast is offline  
Reply With Quote
Old 01-29-2007, 08:54 AM
  #7  
bob27s
My Feedback: (19)
 
bob27s's Avatar
 
Join Date: Apr 2002
Location: Cleveland, OH
Posts: 5,576
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: New DD


ORIGINAL: Rudeboy

A 7.4x8 APC "carbon" prop would be a good place to start.
I agree.... when using the fan engine, use the QM40 carbon APC props

Bob
bob27s is offline  
Reply With Quote
Old 01-29-2007, 11:41 AM
  #8  
proptop
My Feedback: (8)
 
proptop's Avatar
 
Join Date: Oct 2002
Location: Rome, NY
Posts: 7,022
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

Woo-Hoo Chuck! You gonna whup my behind with that one...[X(] Sure should be a lot faster than the old Dago Red...I need to get to work on my "secret weapon".

Karl,
Very interesting, especially the rotating of the carb for N.V. clearance.[8D]
Awesome!
Hope spring gets here soon man...this cold weather stuff sucks![:'(]
proptop is offline  
Reply With Quote
Old 01-29-2007, 03:30 PM
  #9  
nitro junky
Member
Thread Starter
My Feedback: (3)
 
nitro junky's Avatar
 
Join Date: Aug 2005
Location: canastota, NY
Posts: 78
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

freakingfast Thank you very much

I think after all of your advice I will build another one and set it up a little different. There is alot of things I did not do becuse I was not sure what engine I was gone to end up with.

How fast have you clocked yours in the air?
nitro junky is offline  
Reply With Quote
Old 01-29-2007, 04:04 PM
  #10  
samuelx
 
samuelx's Avatar
 
Join Date: Jun 2004
Location: Tampere, FINLAND
Posts: 62
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

If you want to keep it light and powerfull I can sell you some of my IR 40 F3D motor´s. They are spinning 6,7"x8" prop 32.000 RPM on FAI Fuel. If you use nitro....[>:]


Here is some photos on IR motors:
http://www.rcuniverse.com/forum/fb.asp?m=5341425
samuelx is offline  
Reply With Quote
Old 04-17-2007, 03:23 PM
  #11  
nitro junky
Member
Thread Starter
My Feedback: (3)
 
nitro junky's Avatar
 
Join Date: Aug 2005
Location: canastota, NY
Posts: 78
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

It's been sometime but I just got the engine on the plane. I have run it twice now to get the pipe tuned in and to start breaking the engine in. I am runing Power Master 30%Heli fuel and the engine is only running around 190 F. I think I may up the nitro to 40% and see where the temp is. Now if we could only get rid of this ^&%$#*& snow and I can find the balls to fly it I will be all set, I think
Attached Thumbnails Click image for larger version

Name:	Vt57836.gif
Views:	9
Size:	101.7 KB
ID:	666711   Click image for larger version

Name:	Rn39341.gif
Views:	9
Size:	111.3 KB
ID:	666712  
nitro junky is offline  
Reply With Quote
Old 04-17-2007, 03:47 PM
  #12  
proptop
My Feedback: (8)
 
proptop's Avatar
 
Join Date: Oct 2002
Location: Rome, NY
Posts: 7,022
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

Chuck...give me some advance notice before ya test 'er out...I'll help ya, and I wanna see it go![sm=thumbup.gif][8D]
proptop is offline  
Reply With Quote
Old 04-17-2007, 03:56 PM
  #13  
bob27s
My Feedback: (19)
 
bob27s's Avatar
 
Join Date: Apr 2002
Location: Cleveland, OH
Posts: 5,576
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

I'd not pay much attention to the temperature. Does not really mean much with an aircraft engine (this type of model aircraft engine)

The fan engine is not designed for high nitro --- stick with 30% or less.
bob27s is offline  
Reply With Quote
Old 04-17-2007, 05:01 PM
  #14  
coydog
My Feedback: (2)
 
Join Date: May 2004
Location: oneida, NY
Posts: 39
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Can any one suggest a good prop

o.s. calls for fuel with 20% MINIMUM lubricant content and 20%-50% Nitromethane
coydog is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service