Turnbuckle Safety Wiring Questions

farmrjohn

Pre-takeoff checklist
Joined
Mar 26, 2018
Messages
453
Display Name

Display name:
farmrjohn
My service manual specifies safety wiring a turnbuckle per MS33591 which is the double warp method in 43-13-1B. Doing that in the space available is "challenging". MS33591 also says for designs after 1 May 67 to use the clip method for safetying. Can the MS clip style turnbuckles be substituted for those requiring safety wiring? If so, would the correct combination of MS components to replace an AN140-16S turnbuckle be:
MS21251-B3S Barrel
MS21255-3LS Cable Eye
MS21255-3RS Cable Eye
MS21256-1 Clips
 
Can the MS clip style turnbuckles be substituted for those requiring safety wiring?
Yes. There is an AC or some guidance document that allows either type turnbuckles provided all components of the turnbuckle are designed to accept the clip. If not then safety-wire is required. Your P/Ns look good but can't pull up a book to confirm.
 
Just submitted an article on the MS series turnbuckles. Yes, you can do conventional safety-wiring, and in some places, it'd be easier than the clips used by the MS series. The clips require a very precise "clocking" between the barrel and the turnbuckle end. Moderately simple to do when you have good access to the turnbuckle, but a bit tougher when it's hard to get at the turnbuckle.
ms turnbuckles.JPG
Just got done installing eight of these on my Fly Baby, along with new cables and shackles. I SERIOUSLY hate safety-wiring turnbuckles (for good reason, there are 41 on a Fly Baby). So I decided to use these rather than the conventional safety wiring. It's...a bit of a hassle. Practice in your easy chair before trying to do it for real.

But when they're done, I do like the clean look.
turnbuckle finished.JPG
And yes, the turnbuckle on the far side DOES have the clips in.

The other issue that might bother some is that the bodies and ends can only be locked at 180 degree intervals. If you're the kind of guy who wants an extra quarter-turn, you'll need to use the conventional safety wiring.

Here's the table I developed comparing the proper components to the AN series turnbuckles.

ms turnbuckle specs.JPG
And...the last bit of good news: Even having to buy the three components separately, an MS-type turnbuckle costs HALF what the equivalent AN series runs....

Ron Wanttaja
 
Just submitted an article on the MS series turnbuckles. Yes, you can do conventional safety-wiring, and in some places, it'd be easier than the clips used by the MS series. The clips require a very precise "clocking" between the barrel and the turnbuckle end. Moderately simple to do when you have good access to the turnbuckle, but a bit tougher when it's hard to get at the turnbuckle.
View attachment 111518
Just got done installing eight of these on my Fly Baby, along with new cables and shackles. I SERIOUSLY hate safety-wiring turnbuckles (for good reason, there are 41 on a Fly Baby). So I decided to use these rather than the conventional safety wiring. It's...a bit of a hassle. Practice in your easy chair before trying to do it for real.

But when they're done, I do like the clean look.
View attachment 111519
And yes, the turnbuckle on the far side DOES have the clips in.

The other issue that might bother some is that the bodies and ends can only be locked at 180 degree intervals. If you're the kind of guy who wants an extra quarter-turn, you'll need to use the conventional safety wiring.

Here's the table I developed comparing the proper components to the AN series turnbuckles.

View attachment 111520
And...the last bit of good news: Even having to buy the three components separately, an MS-type turnbuckle costs HALF what the equivalent AN series runs....

Ron Wanttaja

Very nice work. Thanks for sharing your information.
 
Back
Top