Interesting Observation - Traxxas Spartan Flex vs. Quality Aftermarket Flex

[dag-nabit]

While repairing my Spartans over the past couple afternoons I observed something interesting about the Traxxas Spartan OEM Stock Flex Cable and a Quality Aftermarket Flex Cable.

In this case, a cable from Jeff Wohlt, but I suspect the comparison would be about the same with any quality aftermarket cable.

Rather than try to describe it, I did up a cheezy little video. I apologize upfront for the amateur effort, but videos and editing are not my forte.


http://www.youtube.com/watch?v=TwE25NPUP_M

Kevin

[Jeff Wohlt]

Nice video... Nothing gets that much bend but does prove a point! Even spelled my last name right!! :)

[dag-nabit]

Nice video... Nothing gets that much bend but does prove a point! Even spelled my last name right!! :)

Of course the shafts would never see that much bend in a running application, but if they are mishandled during shipping or storage, it is something to watch for.

That is what brought my attention to it, I had ordered a couple Stock cables to get me through until my aftermarket cables arrived. They had been shipped "doubled over", not kinked, but fairly tightly looped back to fit a mailing envelope. I noticed the cables seemed to be holding the shape a bit, so I straightened them out and then tried this "test".

Also makes me wonder, if the cables are "corkscrewing" or torque twisting under load, maybe the stock cables could start to kink a bit??

Kevin

[Doug B]

The tendency to retain its curvature could influence it in its stock application I would think, and after seeing the pictures of the broken cables too, its very obvious that it pays to get the best available when it comes to cables and driveline parts. Especially when you think of the job that the cable does, those strands are shifting and moving in small amounts throughout the entire run. Moreso for people that push the limits. I think the need to leave some space between the drive dog and the strut should give an indication of the amount they contract when spun up.

[GeoVW72]

I've noticed the same with the new stock cables I got. Went away after it was run, seems like it was pre-loaded when it was glued or soldered. You also have to remember that it's not only taking the torque of the motor/prop, but also the point of force that pushes the hull through the water.

I guess the stock cable was speced because of cost, proboat uses something similar but at a lower load and theirs is also cadmium coated like ocutra.

Here's my contribution(also "unscientific");
https://lh4.googleusercontent.com/-jV-qILqAcX8/TffzyJ2cHxI/AAAAAAAAA8Q/202iRpKJc1o/s640/IMG_20110614_150109.jpg
Jeff's cable torqued an 1/8 turn(based on set screws) and pulled taught(based on the static friction of the vise on the counter)
https://lh5.googleusercontent.com/-Mevj7-WOroM/Tffz0ZHk34I/AAAAAAAAA8U/V8tJX7Cuub4/s640/IMG_20110614_150321.jpg
Stock cable, same load(close enough)

The stock cable is very stiff, maybe too stiff :confused2:

[Jeff Wohlt]

And this is what a cable is doing in the stuffing tube...you wont have this with wiredrives...just creates friction in the liner and melts them...which we have seen plenty of

[airman66285]

And this is what a cable is doing in the stuffing tube...you wont have this with wiredrives...just creates friction in the liner and melts them...which we have seen plenty of
Jeff,
Please forgive my ignorance regarding wiredrives but does a wiredrive have to be perfectly straight in installation or can there be some curve or deflection in it? Put another way, will a wire drive work in the Proboat Miss Geico or is there too much bend in the stuffing tube for it to work properly?