RC Scale Aircraft Discuss rc scale aircraft here (for giant scale see category above)

How to use turnbuckles?

Reply
Old 11-22-2010, 08:58 AM
  #1
Trev
Thread Starter
 
Join Date: Apr 2003
Location: Dublin, IRELAND
Posts: 210
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default How to use turnbuckles?


This may seem like a stupid question on a scale forum, but how exactly are turnbuckles used to tension flying wires?

Having used only non-scale clevises so far, I was wondering if the 2 threaded eyelets (and the attached wires) are twisted during adjustments?

Or does the center bit (loop?) have counter-rotating threads with both eyelets staying 'in plane' but going in or out when the latter is twisted?

What is the best method to secure turnbuckles once the desired tension is achieved?

Finally, I was thinking of ordering some nice looking brass turnbuckles from this supplier
http://arch.navalis.pl/

Has anyone used products from them before?
Trev is offline  
Reply With Quote
Old 11-22-2010, 09:21 AM
  #2
Lnewqban
 
Lnewqban's Avatar
 
Join Date: Apr 2007
Location: South Florida
Posts: 4,037
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

A RCU search has returned these threads:

http://search.rcuniverse.com/search....hwhere=subject
Lnewqban is offline  
Reply With Quote
Old 11-22-2010, 09:55 AM
  #3
abufletcher
 
abufletcher's Avatar
 
Join Date: Feb 2004
Location: Zentsuji, JAPAN
Posts: 15,018
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

Trev, the two end pieces (whether eyes or forks) are right and left hand threaded so that rotating the barrel of the turnbuckles pulls them both inward or outward. So to set up your turnbuckles you need to have them at almost their full extension, then make the wires as without slack as possible by hand. Then you can rotate the body to pull the wires to flying tension. After the tension is set you need to use safety wires which wrap around the ends and thread through the middle of the body. Somewhere I have (and have seen on RCU) a diagram showing the proper safety wire technique.
abufletcher is offline  
Reply With Quote
Old 11-22-2010, 10:34 AM
  #4
abufletcher
 
abufletcher's Avatar
 
Join Date: Feb 2004
Location: Zentsuji, JAPAN
Posts: 15,018
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

Ah, here it is:

abufletcher is offline  
Reply With Quote
Old 11-22-2010, 10:49 AM
  #5
LesUyeda
Banned
 
Join Date: Oct 2002
Location: San Diego, CA
Posts: 2,670
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

Trev: Use great caution when tightening turnbuckles!! It is very easy to pull things out of alignment with them.

LEs
LesUyeda is offline  
Reply With Quote
Old 11-22-2010, 11:08 AM
  #6
Teus
 
Teus's Avatar
 
Join Date: Jan 2007
Posts: 765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

Quote:
ORIGINAL: Trev


What is the best method to secure turnbuckles once the desired tension is achieved?

Just finished securing 75 turnbuckles I did it with 0.3mm steel wire.
Teus is offline  
Reply With Quote
Old 11-22-2010, 11:42 AM
  #7
abufletcher
 
abufletcher's Avatar
 
Join Date: Feb 2004
Location: Zentsuji, JAPAN
Posts: 15,018
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

OK. So where's your EIII thread again? I know it's over on RCSB somewhere, but I always have a hard time finding anything there. I suppose it's under Proctor builds, right?

*****

Nevermind! Found it. I do feel like joining the fun over on RCSB, but I'm just so cozy here on the RCU Scale forum.
abufletcher is offline  
Reply With Quote
Old 11-22-2010, 10:40 PM
  #8
destrat
 
Join Date: Jan 2004
Location: Canby, OR
Posts: 118
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

Trev:

As an aircraft mechanic, I deal with turnbarrels all the time and the other guy's are definetly right when it comes to tightening them up. One thing that I would do is leave a little slack in the cable, this can be adjusted before you crimp the swage. A little experimenting will tell you just the right amount. The reason being that these modelling turnbarrels have way fewer threads than a full size one and you need to have some thread engagement inside the barrel. I usually leave about 4 threads showing on the eye or clevis end. Remember to not tighten to much and you'll be just fine.
destrat is offline  
Reply With Quote
Old 11-23-2010, 03:10 AM
  #9
abufletcher
 
abufletcher's Avatar
 
Join Date: Feb 2004
Location: Zentsuji, JAPAN
Posts: 15,018
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

That sounds like dead-on advice. I'll add that on the ground/bench landing wires should be "taut" and the flying wires just a bit slack. In the air or with your fingertips under the wingtips, the flying wires should be taut and the landing wires a bit slack. The question here is the relative meanings of "taut" and "slack." I take "taut" to be tight enough so the wire makes a low "thuwung" sound when plucked. This isn't very tight and it doesn't need to be. You're not tuning a guitar. It just has to be tight enough to hold the wings where they are under flight loads...and a fraction of a bit more dihedral never hurt anybody.
abufletcher is offline  
Reply With Quote
Old 11-23-2010, 07:58 AM
  #10
Trev
Thread Starter
 
Join Date: Apr 2003
Location: Dublin, IRELAND
Posts: 210
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?



Thanks everyone for the helpful comments and advice! Also in particular for the words of caution (Les, destrat), my naive approach would've been to tighten them up like guitar strings!

Teus from what I can see that's a great looking EIII! Proctor right? Is your thread over on RCSB?

Abu, cheers for the safety wire illustrations!
Trev is offline  
Reply With Quote
Old 11-23-2010, 10:22 AM
  #11
Teus
 
Teus's Avatar
 
Join Date: Jan 2007
Posts: 765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to use turnbuckles?

Quote:
ORIGINAL: Trev

Teus from what I can see that's a great looking EIII! Proctor right? Is your thread over on RCSB?
Thats right Trev, you can find it here: [link=http://www.rcscalebuilder.com/forum/forum_posts.asp?TID=15817&PN=1&TPN=1]Fokker E.III a Dutch build[/link]

Teus
Teus is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

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



All times are GMT -8. The time now is 02:01 PM.