Go Back  RCU Forums > RC Airplanes > Questions and Answers
Reload this Page >

Attention Ultra Sport builders!!

Notices
Questions and Answers If you have general RC questions or answers discuss it here.

Attention Ultra Sport builders!!

Old 12-07-2006, 11:08 PM
  #1  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default Attention Ultra Sport builders!!

I'm facing a small dilema. I'm plans building a 60 U.S. from RCM plans. I am currently building the wing. I finished the bottom of the wing, and reversed the TE jig and flipped the wing over to work on the other side. The instructions say to lay the wing's spar flat on the board and the TE on the jig.

This isn't working.

If I put a 1/2 spacer under the spar at the outer rib, the TE will lie flat on the jig. The wing will not lie flat on the jig otherwise. This provision is not in the instructions. If I pin the spar flat on the board, I will twist all the washout out of the wing-I don't want to do this.

Can anyone who has built this bird explain to me what I'm doing wrong-or correct for that matter?

I downloaded and printed the manual that Great Planes has on their website, and this is not dealt with in there, either.

I'm fairly sure I can download a picture or two to show what I'm trying to explain if I'm coming across as clear as mud.

Please help.
Old 12-08-2006, 11:04 AM
  #2  
MinnFlyer
Senior Member
My Feedback: (4)
 
MinnFlyer's Avatar
 
Join Date: Apr 2002
Location: Willmar, MN
Posts: 28,519
Likes: 0
Received 5 Likes on 5 Posts
Default RE: Attention Ultra Sport builders!!

Well, first off, there should be no washout in the US wing. Maybe your jig is wrong?
Old 12-08-2006, 11:10 AM
  #3  
RCKen
RCU Forum Manager/Admin
My Feedback: (9)
 
RCKen's Avatar
 
Join Date: Jul 2002
Location: Lawton, OK
Posts: 27,258
Likes: 0
Received 13 Likes on 11 Posts
Default RE: Attention Ultra Sport builders!!

That's what I was thinking too. I had to go back and pull out the instructions for the Ultra Sport (I have both the GP instructions and the RCM instructions). When you turn the wing over it needs to sit flat on the TE jig. If it doesn't then you are going to build a warp into the wing. That TE jig and keeping the spar flat on the table is what builds the wing straight and true. If your wing won't sit flat on the TE jig when you turn it over it's got some warp built into it. Until you put the sheeting on the opposite side of the wing a little bit of warp isn't a big issue. Pinning the wing to the TE jig can take that warp out when you sheet the second side. But if you sheet the second side and you have warp in the wing then it's going to be permanently in the wing.

Hope this helps

Ken
Old 12-08-2006, 11:17 AM
  #4  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Minn is right...no washout.

Pin the spar down flat to your building surface. Your building surface IS flat isnt it?
Dont assume...check it.

It sounds like you may have built a twist into your wing panel.
This is surprisingly easy to do.

I didnt have any particular problem with this when I built mine.
The tapered stock under the trailing edge worked out just fine.

If you havnt seen it yet I have a series of build photos I took when
I was building mine. I am currently working on a new web page
adding commentary to the photos. I should have it up in a few days.

http://tesla-2.dyndns.org/~mhammer/us60/

Mike Hammer
Old 12-08-2006, 12:42 PM
  #5  
Charlie P.
 
Charlie P.'s Avatar
 
Join Date: Feb 2003
Location: Port Crane, NY
Posts: 5,088
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Ilikebipes,

Are you by chance old enough to remember milk deliveries and cars with vent windows? I haven't built a wing with wash-out since my free-flight days. Modern "high power" designs just don't build that way until you get into some of the tapered wings.

Ah, for the old days when wings were important features on a plane. Now they are just a place to hang control surfaces.
Old 12-08-2006, 07:44 PM
  #6  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Wow. I'm definitely doing something wrong here.
I have no problems starting over if I need to here, but I'd like to show you some pics to see where I went wrong, and why I thought there should be washout in the wing. As I studied the plans, it also seems the top of the wing should be straight and flat across with dihedral on the bottom. I'm thinking the TE jig establishes that. And as you get out to the outer wing, the front of the symmetrical ribs are angled down due to the shape of the jig(the back of the ribs are pushed up). Doesn't that give washout?

This is my first build of a double tapered wing, so my understanding of these plans could be way off, but the Great Planes instruction book seems to confirm my thoughts.
Old 12-08-2006, 08:08 PM
  #7  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

As I studied the plans, it also seems the top of the wing should be straight and flat across with dihedral on the bottom.
This is correct. You should be able to lay a straightedge across the top of the wing.

I'm thinking the TE jig establishes that.
No. The wing taper establishes it.

And as you get out to the outer wing, the front of the symmetrical ribs are angled down due to the shape of the jig(the back of the ribs are pushed up). Doesn't that give washout?
Only if your wing is twisted. And the back of the ribs is not pushed up.
The tapered jig just accounts for the taper in the wing allowing you to build
on a flat surface.

I think what you need to do is what RCKen suggested. If you have not sheeted the bottom yet then
pin down the wing the way its supposed to be. Use weight if you have to. You want the spar flat
on your board and the trailing edge resting on the tapered jig. Once you have it that way attach
the remainder of the sheeting. That should hold it in the proper shape.

Also note you need to leave some of the bottom sheeting off in the center until you have joined
the two panels and added the wing dowels.

Mike Hammer
Old 12-09-2006, 01:28 AM
  #8  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

XTOL, I got your pm, I'll be writing you.

Pictures?
[img][/img]


Guess not. [sm=48_48.gif]
Old 12-09-2006, 11:38 AM
  #9  
MinnFlyer
Senior Member
My Feedback: (4)
 
MinnFlyer's Avatar
 
Join Date: Apr 2002
Location: Willmar, MN
Posts: 28,519
Likes: 0
Received 5 Likes on 5 Posts
Default RE: Attention Ultra Sport builders!!

Bipes, Read this thread to learn how to post pics:

http://www.rcuniverse.com/forum/m_2629917/tm.htm
Old 12-09-2006, 06:36 PM
  #10  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

[img][/img]
Attached Thumbnails Click image for larger version

Name:	Yw66398.jpg
Views:	36
Size:	33.8 KB
ID:	574354  
Old 12-09-2006, 07:06 PM
  #11  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Well its hard to tell from your picture but that wing definitely looks twisted.
I think you may have used the trailing edge support jig backwards.

The taller end goes at the root end of the wing and the shorter end at the tip.

If thats what you did then it may not be possible to fix it. It might be
best to start over. Hopefully you didnt already build both panels that way.

Mike Hammer
Old 12-09-2006, 07:08 PM
  #12  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

[img][/img]
Attached Thumbnails Click image for larger version

Name:	Da83531.jpg
Views:	18
Size:	40.7 KB
ID:	574369  
Old 12-09-2006, 07:13 PM
  #13  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

That second picture clinches it. You used the jig backwards.
Well at least you know what the problem is now.

Mike Hammer
Old 12-09-2006, 07:13 PM
  #14  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Hang on-I've got more pictures, but I can only do one at a time without getting timed out!

[img][/img]
Attached Thumbnails Click image for larger version

Name:	Qo40641.jpg
Views:	13
Size:	33.8 KB
ID:	574388  
Old 12-09-2006, 07:15 PM
  #15  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Thank you!!!! Now I can get it right!!!
Old 12-09-2006, 07:20 PM
  #16  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

I guess it isnt real clear on the plans how that jig is to be used.
I never gave it a 2nd thought since Ive built a number of Kaos
wings that are built the same way. Jig blocks are used
on the Kaos instead of a tapered jig but the theory is the same.

I will make mention of this on my Ultra Sport web page. Hopefully
it will help someone else from making the same mistake. I hope
to have it live in a few more days.

Mike Hammer
Old 12-09-2006, 07:30 PM
  #17  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

It's a great help. I look forward to see it when it is completed!! And, I hope someone can be helped by this specific clarification.

One last picture for laughs!!
[img][/img]
Attached Thumbnails Click image for larger version

Name:	Om34027.jpg
Views:	9
Size:	40.9 KB
ID:	574393  
Old 12-09-2006, 07:59 PM
  #18  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

One last picture for laughs!!
Hmm...I had assumed you were a little older...

Oh well. Never too young to start.

Mike Hammer
Old 12-09-2006, 09:57 PM
  #19  
Flying freak
Senior Member
 
Join Date: Jun 2006
Location: granby, QC, CANADA
Posts: 1,407
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

ok i read this thing and well im confused as hell and i would like someone to please clarify as i will be starting an ultra sport build soon (like one i finch my current project) anyways its the kit it will me our first kit so please tell me simply what i have to watch for

thanks a million

Steven
Old 12-09-2006, 10:12 PM
  #20  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

The kit will give you instructions on how to build a Trailing Edge (TE) Jig. They fail to tell you the tail of rib W-1 is jigged at the highest point of the TE Jig, and rib W-11 is at the lowest part of the jig. Since I have never built a double tapered wing before(which this is), I though that the designer was simply trying to build washout into the wing with the TE Jig reversed. I was wrong. I was also confused as to what part the jig plays in the dihedral. Again, I was wrong-it plays no part in the dihedral of the wing.

Did I clear the mud for you any?

-Bipes
Old 12-09-2006, 11:09 PM
  #21  
RCKen
RCU Forum Manager/Admin
My Feedback: (9)
 
RCKen's Avatar
 
Join Date: Jul 2002
Location: Lawton, OK
Posts: 27,258
Likes: 0
Received 13 Likes on 11 Posts
Default RE: Attention Ultra Sport builders!!

Flying freak,
If you are building from a GP kit, the intructions do tell you how to set the TE (trailing edge) jig. This is taken directly from the GP Ultra Sport 60 manual, available on the Great Planes website at [link]http://greatplanes.com/manuals/us60-manual-pt1.pdf[/link]

12. Insert the rear ends of the ribs into the notches in
the TE, then block up the TE with the 1/4" balsa TE Jig
supplied. NOTE: The narrow end of the TE jig is at rib
W-ll. Pin the jig to the building surface
Hope this helps

Ken
Old 12-09-2006, 11:25 PM
  #22  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Sure enough-page 10.

There is even a picture to boot. I past this point before I found the Great Planes Instruction manual.
Old 12-10-2006, 02:22 PM
  #23  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Has anyone considered using 1/16 inch sheeting verses 3/32? I have a friend that shaved almost 3lbs off of his Global Raven, and that is one of the things he did and suggests.

Any opinions?
Old 12-10-2006, 02:47 PM
  #24  
XTOL
Senior Member
 
XTOL's Avatar
 
Join Date: Oct 2004
Location: Galesburg, IL
Posts: 571
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!


ORIGINAL: Ilikebipes

Has anyone considered using 1/16 inch sheeting verses 3/32? I have a friend that shaved almost 3lbs off of his Global Raven, and that is one of the things he did and suggests.

Any opinions?
You mean the wing sheeting? No I would not do this.
I built a Sig Somethin Extra a couple of years ago and the
wing sheeting on it is very thin. Ive had to do repairs to
it 3 different times. The first time I broke the sheeting while
trying to cover the wing.

While it may work out OK on a 40 size plane remember you are building
a 60 size plane here. Dont worry about the weight too much. Mine came
out over 8 pounds and flies like a dream. I tend to build strong rather than light.

Mike Hammer
Old 12-10-2006, 03:17 PM
  #25  
EscapeFlyer
Senior Member
Thread Starter
My Feedback: (1)
 
EscapeFlyer's Avatar
 
Join Date: Aug 2003
Location: Brooklyn Center, MN
Posts: 2,396
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Attention Ultra Sport builders!!

Dont worry about the weight too much. Mine came
out over 8 pounds and flies like a dream.
Okay.

I'm considering pattern(sportsman class). That is why I was thinking about shaving weight where possible. I was thinking about building a "back up" plane also for those "you just never know" situations.

I still might do it just to see what happens. I do appreciate your opinions though, I take them to heart. So please keep them coming.

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.