Re: plastic clevis pin
 

Hi Gang,
On all my planes I have the plastic horns and clevis pins.
Several people told me to remove them and replace them with the metal ones because that thin pin on the clevis that goes through the horn has been known to have many failures.
I would also like some input on screw lock connectors as I have been told they have been known to come lose no matter how tight you crank them down.
Any suggestions are appreciated

Re: plastic clevis pin
 

The pins break on the plastic clevis's. It happened to me on a preflight. I grabed the elevator and gave it a wiggle, then it was free. Would have been bad had it broke in flight. Mostly a problem with age and wear and tear. Saw a buddy lose a 40 sized corsair. Beautiful dive from about 250' at 45deg angle straight into the ground. Broke elevator pin was cause of the crash. At least replace them on the elevator. I've never had a rudder or aileron problem with them, but they dont see as much stress as the rudder. They would probably be ok on 40 or smaller sized planes that are not high stress flyers, (quicky type flying). I only use them on throttle or other low stress area, definately not on a flight surface.

Re: plastic clevis pin
 

Yup, gotta agree here. Just go ahead and toss all of those nylon clevises, if they ain't broke yet, they will be some day!!

When replacing them with metal, be sure that you have the correct thread size. There is one metric thread size that will thread onto a 4-40 pushrod but will slip with little force. Also, use a lock nut with the metal clevises.

Re: plastic clevis pin
 

whirly Bird, are you sure those were nylon, not plastic? In general good nylon clevises are as reliable if not more so than the metal ones. They wear much better and are more than adequate in strength. If you are in a very dry climate (desert conditions) nylon does dry out and weaken but that is a rare occurance. I have some planes I've been flying for over ten years with nylon clevises and no problems.

Re: plastic clevis pin
 

Nylon is a polyamide resin. It is also a plastic. So are over a dozen different types of industrial resins.

I really don't feel to comfortable with nylon clevises in planes over 4 or 5 pounds. Steel clevises just seem more durable in the long run.

Re: plastic clevis pin
 

I don't use plastic or nylon clevises on anything powered. I have had them break, and also the vibration strips them off the metal rod. I only use metal. Also, the dubro quick lock connector with the screw is bad on power. I might use it on a throttle now and then, but there are 2 ways it can come loose. The bolt can loosen or the rod slip, and the snap on holder can come loose and it can fall out of the arm. They are kind of scarey. I wouldn't use them on a power plane period. I learned the hard way and lost a plane from a plastic clevis letting go. Hope you learn by that too so it doesn't cost you a plane.

Re: plastic clevis pin
 

Fly boy.
Several others told me to set my throws,double check everything then count the turns while unscrewing the clevis and coat the threads with lock tite.
I read on another thread that the metal ones can cause qlitches :confused:

Re: plastic clevis pin
 

Hi Rodney,
Yes,
They are NYLON and not plastic.

Re: plastic clevis pin
 

Thats a real bummer and a real loss over a $1.00. item.Sorry to hear that :(

Re: plastic clevis pin
 

Thanks for the post here ilikeplanes.
It looks like most are in favor of the metal ones.
I thought I saw a post on a ball joint clevis but I don't see it here.
All of my planes range from 7-9 pounds and 9 pounds is getting to the point where I am concerned even though I fly out from a farm