stunthanger.com

General control line discussion => Open Forum => Topic started by: Bootlegger on March 30, 2011, 05:28:15 AM

Title: vector 40 profile
Post by: Bootlegger on March 30, 2011, 05:28:15 AM
 #^  Mornin guy's, I have been seeing and hearing about V40 profiles, and my interest is charged up.
    Can the fellow's that have built one share what changes thet made with us.
  Engine thrust line and any other things that will help.    ~>
Title: Re: vector 40 profile
Post by: Roger Vizioli on March 30, 2011, 08:46:35 AM
Gil,
I saw Gene Martine flying one years back in the Jacksonville area, I think (?     ???) it was at USN Whitehouse. I believe it belonged to Tom Weedman, ie x47 Flyers. As I recall, it flew great.
Roger V.
Title: Re: vector 40 profile
Post by: Bill Little on March 30, 2011, 12:24:34 PM
Call me dumb, but I don't see a need to change anything..........

I have seen a ton of profiles built from "built up fuselage" planes and they flew very well.  I can't "see" a need for changing the thrust line, etc.. ???

Big Bear
Title: Re: vector 40 profile
Post by: tom_weedman on March 30, 2011, 01:35:27 PM
I have flown one for two years built one for A club member and building A new one now. Power it with A LA 46 Tunder Tiger 11-4.5 prop 62 foot lines that works good for me. I use two pieces of quarter inch balsa with carbon mat lamanated between for the body to stifin up the tail build it straight and go have fun.
Thanks Tom Weedman AMA 63672
Title: Re: vector 40 profile
Post by: Bootlegger on March 30, 2011, 06:12:01 PM
 %^@   When I was talking about change's in the thrust line I should have asked how do you keep the thrust line where it is so that everything will remain the same for alignment.
  I want to have the model fly as it should.
  Hope that this clears up any "fas paux"  on my part.     #^
  Thanks again, Gil
Title: Re: vector 40 profile
Post by: Roger Vizioli on March 30, 2011, 06:27:31 PM
Tom,
Thanks for verifying that my old mind still rmembers (important things) correctly!   LL~
Roger Vizioli
Title: Re: vector 40 profile
Post by: Bootlegger on April 01, 2011, 12:29:30 PM
 H^^       Thanks guy's, I appreciate the help.
Title: Re: vector 40 profile
Post by: Balsa Butcher on April 01, 2011, 05:00:40 PM
I'd just attach the original plan's side profile to a flat board. Tape together tracing paper and attach that over it. Using the original outlines, draw your profile fuselage on the trace paper. As for the front end, keep the thrust line where it is indicated by the original plans and make your cut-out the width you need to insert and engine and engine mounts. As for the doublers, tank mounts, that's your call.  The tracing can be attached to poster board and cut out to make a more durable template. Sounds like a fun project. 8)
Title: Re: vector 40 profile
Post by: Bill Little on April 02, 2011, 11:34:05 PM
HI Gil,

As Pete said, just use the edge of the motor mounts the engine bolts to since that is the thrust line.  Measure up and down from it to set the profile motor mount widths.  I would run the motor mounts as long back towards the wing as feasible, and the ply doublers to at least the high point of the wing.  And maybe inlet a piece of maple motor mount where the LG bolts will go.

Big Bear
Title: Re: vector 40 profile
Post by: Serge_Krauss on April 03, 2011, 12:19:56 AM
If they fly well, then they fly well. Fine.

However, the main concern in switching from a full fuselage to a profile is to keep the vertical c.g. where it needs to be. When the engine is rotated from cylinder-down to "sidewinder", that raises the c.g. height.  This is a line tension and roll thing, while compensational changes would be pitch oriented. I imagine that the top aerobatic fliers might see a difference.

SK
Title: Re: vector 40 profile
Post by: Bill Little on April 03, 2011, 12:29:23 AM
HI Serge,

Since the weight gets distributed in line with the thrust line, maybe it doesn't affect it much.  Having done this, and seen it done, with a few models over the years, I have never seen a case where the "wings level" were affected. ???

Big Bear