I noticed that the arf's are using fastlinks to fasten the servo's to contron horns and servo arms how safe are they and has anyone had a problem with them coming loose?

Thnk you,
Ken

IMO, it depends on the size of the plane, personally I wouldn't use them on a critical flight surface on a 40 size or larger plane

Andrew if you are talking about the ninety degree bend in the 2/56 wire with a plastic keeper, They are perfectly fine and reliable but I never use them for two reasons first they are difficult to remove and reinstall but most important they inhibit the servo arm when the closet hole is used and more folks need to use the closest hole to the servo on their trainers . This is especially so on a nose wheel push rod because typically far to much throw is used on this rod.

John

Never had a problem, but stopped using them because they are a pain (literally).

The use of these things has been hotly debated over the past few yearrs. They are like Howard Cosell. The people who like them really like them and the people who don't like them really don't like them. I have used them in certain planes and have found that if you get the set screw really jammed into the wire, they don't come loose.

Is thd question about easy connectors? The little round brass critters. I have seen them steel/chrome in some ARFs?

The Great Planes version of those little critters are called "screw-lock pushrod connectors" and the main body is brass and square in cross section. It uses a socket head cap screw (allen wrench bolt) to squeeze down on the pushrod wire to secure it. I only use this type on throttle pushrods as I am one of those that don't trust them for control surface use. I always put a drop or two of Loctite on the screw and have not had any problum. Be aware that if the pushrod wire is too thin the head of the allen screw will bottom against the top surface of the connector before clamping the pushrod wire. I like them for throttle use as it is easy to adjust the linkage to the carb. The Great Planes version of other type that has a 90 degree bend in the wire going thru the nylon keeper that then snaps onto the pushrod wire are called "faslink pushrod keeper" by G.P. I use these without problums on control surfaces of small to medium size (40-60) sport and scale planes. I do add a small piece of fuel line as a safety retainer as is common practice on regular clevis instalations. John Buckner is correct that this type can interfere with the servo arm when used in an inboard arm hole so be aware and notch the keeper if needed. On large 1/4 scale or fast high load applications I like metal threaded or soldered clevis connections or pull-pull cables. Andrewskj, there many different ways to build and outfit these things and with experience everyone finds techniques and parts that work for them.

The scew version I use on throttles (sometimes as a retainer to hold the wire with a 90° bend snug on the throttle arm). The 90° bend version with keeper I use on control surfaces at the servo end right on up to .91 size sportmodels.

I think before we go much further the OP should maybe post a picture of which connector they are talking about...
a google for fastlink shows these:


but based on the above posts...
so it seems that there are several different connectors being discussed...
a little clarification would be wise....