Preventative maintenance - ball links?

[BruceSM]

It is clearly important to check everything, bolts, links etc. before flying. But what about preventative maintenance i.e. routine replacement?
As a newbie, I imagine that one of the most likely items to fail is one of the ball links on the rotating parts of the head - after all, they are only held in place by the strength of the plastic. If one of these failed at 100 feet up, there's nothing we could do but watch (and maybe run!).
So shouldn't they be replaced as a matter of course, BEFORE THEY FAIL? Anyone advise on how many hours before replacement?
And what about tail belt safe running life?
And are there any other parts advisable to replace as a matter of routine maintenance, rather than after damage?

[thecheat]

Acutally as a newbie, they'll probably last longer than the heli, but, you'll know when to replace them if you see slop developing in the linkages.

[BruceSM]

There is some give from day one - but do ball links last 10 hours, 20 hours, 50 hours, less, more? What is the longest anyone has had a ball link last without failing?

[Daz(DJLFlapper)]

Hi,

This is a good question however the ball links are very hard to put a life span on, This is somthing that differs from person to person or Heli to heli. There is no official time to replace ball links, The decision is one that the Heli owner is in charge of. I fly my heli quite regular and I have had the same ball links on it for a couple of years. I check them regular and if I found that any of them did not hold the ball secure then I would get that one changed.
How I check mine is to put a finger in behind the link and if I can pop the link off without having to use a reasonable amount of force then it is changed. this has served me very well over my hobby life.

IF you do find that your ball link has become loose so that you can pop it off without much effort. You could try what I sometimes do. This is not a gaurented fix but it has worked for me. Boil some water in the kettle and wait a few minutes. pop a spare ball into the link and then bip it in the water for a count of 30secs. then take it out and press the link around the ball before dropping it into cold water. This can have the affect of restoring the ball link. I would hwever only suggest that this be done once or twice. You certainly dont want to do it for the sake of a few bucks all the time.

Another factor on the ware of your linkages is the quality of them. I have known links on helis that are very old and I mean Very old, But they still have a good hold on the ball. Flight style is another factor, If your just hovering and doing some fast forward light with gentle transitions then even a weak link can hold well.

There is no answer like 40 hours or more or less. CHECK them and if they seem to be in poor condition then get them changed. Tail rotor drive belts are a simmilar thing also with regards to the time to change them. Inspect you belts thouroughly then if there is a reason for changing it do it. They can last as long as your heli or they can ware very fast if something is not quite right.

The most important thing to remember with your heli and you as the pilot. Is to have a good pre flight and post flight check of your heli. I personally service my helis after every 5 flights, This involves stripping the heli down so that I can examin it properley. This is extra to my post and pre flight checks, Fingers crossed I have not had a machanical failier to date. Something that I am very proud of.

Hope this helps.

[BruceSM]

Thanks Daz. This is a more comprehensive answer than I've found in any of the books. Good flying!

[jahatton]

Here is a suggestion, when your copter is running at peak performance, Make a gige with some plywood and take each pushrod off the head and screw an old ball onto the plywood. Snap the pushrod in place and if there is a pitch on the other end, make a little angle piece to equal the pitch thus you can quickly make a replacement and not change the trim etc...
It's hard to take things apart when its good but in future the maintenance will be a breeze.
In fact it might be a good idea to have extra's in the flight box just in case.. so you won't have any down time.
I did this trick and I was able to get the copter flight ready in just minutes without trim changes.
Hope this will help
Jim

[jahatton]

In the flying I've done since 86 is keeping a log book for every plane and keeping track of every little detail.. Date? how many flights?, where?, Battery checks?, Notes: write down every detail in your problem solving to even a glow plug replacement. I keep tabs on all my maintainence. I cannot be more clear on this part of the hobby.. People forget and fly with something that was supposed to be changed but forgotton. Write it down and do it!

ie: Date Location Tx Rx Flights Fuel Notes

I use the Excel program to log.
Jim

[BruceSM]

Originally Posted by jahatton

In the flying I've done since 86 is keeping a log book for every plane and keeping track of every little detail.. Date? how many flights?, where?, Battery checks?, Notes: write down every detail in your problem solving to even a glow plug replacement. I keep tabs on all my maintainence. I cannot be more clear on this part of the hobby.. People forget and fly with something that was supposed to be changed but forgotton. Write it down and do it!

ie: Date Location Tx Rx Flights Fuel Notes

I use the Excel program to log.
Jim

Excellent recommendation, Jim.
I use the free flightlog which can be downloaded from www.rchelibase.com
Bruce