Hi Folks,

When you buy a pull pull system you seem to get plently of wire but only a few of the metal things you crimp to secure the wire to the connector. What can I use to crimp to hold the wire to the connector. I was thinking copper fuel tubing but I assume the copper is too soft and would not hold the wire tight with time?

Any suggestions?

Thanks

Scott

Go to your nearest fishing tackle store and pick up a bag of crimps for making your own fishing leaders. They cost $1.29 for a bag of 40 the last time I bought some.

John

I have puchased some at the LHS or you can make the from copper tube .
K & S engineering has a rack in most hobby shops with many sizes of tube you can use.
I use copper just big enought to fit three diamiters of wire thru that I am using.
Procor GP and Sullivan also sell prepackeged sets too , DuBro has them also.
Always loop the TAIL back thru and don't rely on just the two wires in the crimp.


Den

This looping business has me confused (I suppose confused is my normal state.). Just what is included in the loop? Would it be possible for some one to post a diagram or picture of what this looping looks like?

Lee

Here is my ultra lame attempt at drawing this in paint.

You end up with the cable passing through the ferrule three times instead of just two. This results in a tighter crimp.

Also, though I have used copper tubing in the past, I do not recommend it. It is too soft. Go to the tackle store and buy the correct ferrule. There's nothing quite like using the right material for the job at hand.

John

The advice to use ferrules from the tackle shop is good. Just remember that they come in all sizes. You want the size to just let two thicknesses of the line you are using go thru. A #4 is what I use on most lines but occasionally need other sizes in order to get a neat and reliable crimp.

No, no, no! You want the size that allows three passes of the cable, not two! See my lame diagram above. With this setup, the cable cannot come completely out of the ferrule. The cable could slip and become loose in flight, but it will not fail completely. I have both A3, 4, and 5 ferrules in my shop for various size cables. Cable size is dependent on the size of the model and it's anticipated flight loads.

John

While we are on the subject of crimps, what is the best tool to do the crimping with?

I use heavy pliers. But, I also crimp the ferrule twice. I crimp each once, 90 degrees to the other end. Looking at the end of ferrule you see a + shape.

John

I have two planes that have been flying for over 5 years, all with the wire only going thru the ferrule twice, once to the eye then back thru the ferrule and crimped once with a proper crimp tool. No way will it back out, no need for the double loop. In an emergency you can make a pretty good crimp with a pair of dykes, just do not squeeze so hard you fracture the crimp area.

I have never had a failure with the cable only going through the ferrule twice either, but since it's so easy and weighs only a fraction of a gram, why not make it even more secure?

FWIW, I have had cables slip out while fishing. But that was before I started adding the loop three pass procedure. Since I started doing this, I've not had a single cable fail. If a fish can pull the cable loose, any considerable force would also be able to do so.

John

I use a vice to clamp down on my crimps, I have never had a failure. Is this generally an OK method?

Any method that works for you that doesn't dammage the ferrule or the cable, is acceptable. Just make sure it's tight.

A vice? How do you do that inside the fuse?

John

I build 'em big!