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Building Tips and technical articles. => Building techniques => Topic started by: Larry Borden on February 18, 2015, 07:47:50 AM

Title: Ball Link Problem
Post by: Larry Borden on February 18, 2015, 07:47:50 AM
I'm building a Mackey ME 109 from scratch, other than a rib set from RSM. I'm using the Du-Bro heavy duty ball link on the flap horn. There is not enough room to put another ball link on the horn for the elevator push rod. Has anyone used the smaller ball links? There is enough room for the smaller link for the elevator rod using one of the smaller ball link.
Any problems using the small one? Using RSM control horn.
Title: Re: Ball Link Problem
Post by: Alan Resinger on February 18, 2015, 10:17:33 AM
Larry,
Can't you put the link on the other side of the horn?
Alan Resinger
Title: Re: Ball Link Problem
Post by: Tim Wescott on February 18, 2015, 10:23:38 AM
It imparts a twisting moment to the flap horn, but that's what I did on my current ride, which has over 500 flights on it with no signs of wear.
Title: Re: Ball Link Problem
Post by: Larry Borden on February 18, 2015, 10:47:21 AM
I'm using nylon insert nuts and there's the problem.  Not enough room because of the nut.  Could use loctite and regular nut. The swivel ball links fit.
Title: Re: Ball Link Problem
Post by: Allan Perret on February 18, 2015, 10:50:25 AM
You could make a custom horn with the two holes offset fore & aft to get needed clearance.  This also helps with control linearity.  
What are the Dubro numbers for the two ball links in question ?
Title: Re: Ball Link Problem
Post by: Chris Belcher on February 18, 2015, 11:24:00 AM
Ran into the same prob with a nobler and oriental. Tom Morris has some good clevises to go back there. Some dont trust em but i've got hundreds of flights on both with no issues.  i wouldnt use just any ol clevis but the ones Tom sells are the best i've seen. Not sure what brand they are but give Tom a call..he's in the vendors corner under stunthanger i believe. Very nice guy and has always been willing to help...
Title: Re: Ball Link Problem
Post by: Chris Belcher on February 18, 2015, 11:26:42 AM
Sorry..its TOMS BUILDING SERVICE and then theres a link to his catalogue...great stuff and great service!!
Title: Re: Ball Link Problem
Post by: Larry Borden on February 18, 2015, 11:39:41 AM
Swivel is 497
Heavy 899
Title: Re: Ball Link Problem
Post by: Tim Wescott on February 18, 2015, 12:04:33 PM
I'm using nylon insert nuts and there's the problem.  Not enough room because of the nut.  Could use loctite and regular nut. The swivel ball links fit.

If it's the 4-40 thread stuff you can get two sizes of nut: one's 1/4" across the flats, the other's 3/16".  I have the small nuts on my Twister, with loctite, and it's working fine (I feel strange giving serious advice based on a Twister.  But dammit, I'm flying in Expert and I'm going to replace that thing as soon as possible!)
Title: Re: Ball Link Problem
Post by: Allan Perret on February 18, 2015, 12:30:20 PM
If it's the 4-40 thread stuff you can get two sizes of nut: one's 1/4" across the flats, the other's 3/16". 
You got a source for the 3/16" across flats.
Title: Re: Ball Link Problem
Post by: Tim Wescott on February 18, 2015, 12:42:29 PM
You got a source for the 3/16" across flats.

Um -- no?  I'm just compulsive about saving every bit of hardware that comes across my bench.
Title: Re: Ball Link Problem
Post by: Larry Borden on February 18, 2015, 01:01:08 PM
Thanks for all the help.   H^^ Got it fixed. The link that I was trying to use may have been one of the metric ones. May have picked up a metric link by mistake. The one I was try to use had a lot more material around the ball and that was the reason it wouldn't fit. Had a case of the dumba--. First time using these things.
Title: Re: Ball Link Problem
Post by: Target on March 21, 2015, 09:59:54 PM
You got a source for the 3/16" across flats.
Who doesn't love McMaster Carr?
http://www.mcmaster.com/#90760a005/=wewxi5
http://www.mcmaster.com/#hex-nuts/=weww96

Regards,
Chris
Title: Re: Ball Link Problem
Post by: dennis lipsett on May 11, 2015, 02:12:03 PM
Larry,

I did this on an Oriental ARC. They have absolutely no room for almost anything back there and this was the obvious solution. Some may complain about the aesthetics of it but I am only concerned with the results.

Dennis
Title: Re: Ball Link Problem
Post by: Bill Little on May 11, 2015, 03:16:19 PM
Larry,

I did this on an Oriental ARC. They have absolutely no room for almost anything back there and this was the obvious solution. Some may complain about the aesthetics of it but I am only concerned with the results.

Dennis

Hi Dennis,

I have to use "scabs" on almost ALL of the Classic models I have done with ball links.  They are basically hidden by the stab anyway! ;D

Bill
Title: Re: Ball Link Problem
Post by: Bill Johnson on May 12, 2015, 05:09:20 AM
Who doesn't love McMaster Carr?
http://www.mcmaster.com/#90760a005/=wewxi5
http://www.mcmaster.com/#hex-nuts/=weww96

Regards,
Chris

If you have clearance issues, I would recommend what we call "missile nuts". McMaster Carr calls them "Jet nuts".
http://www.mcmaster.com/#hex-nuts/=x5aubr  From this link, go to "Flange Nuts", "Steel".
The MS21042 is good in all shear and tension applications up to 160K PSI and 450F. The 4-40 version is only 5/32" across the flats.