Surfmaster 150 - Getting it Ready to Fish

[JasonGotaProblem]

What would make the slipping slick side of the drag washer all of a sudden become the side that grips the metal washer? 

That's gonna keep me up at night.

Shot in the dark: the grease wears off. Now the other side is more slick. I dunno.

[oc1]

Me neither.

[jurelometer]

This all seems to make perfect sense.  But, when the drag is disassembled you never find one side of the drag washer more worn or more slick than the other side.  They wear equally on both sides.  So, the side of the drag washer that is slipping must somehow change back and forth.  What would make this happen?  What would make the slipping slick side of the drag washer all of a sudden become the side that grips the metal washer better?  I suspect that both sides of the drag washer must have been slipping all along.

Interesting...


Both sides cannot slide at the same time as the higher CoF side will not release due to...the higher C0F. Two sticky sides, the stickier side will hold. The holding side will also have an an increased advantage now  due to the static CoF being higher than the kinetic C0F for a material pair.

One possible cause for switching: debris buildup on the slipping side increasing the CoF. Another is drag grease being displaced on the slipping side.  There are probably others.

This part is just my speculation: For the reasons mentioned earlier, I am skeptical that it normally goes back and forth continuously during a run, but once the drag stops, the non-slipping side might now have the lower static CoF and become the slipping side.  But it is pretty tough to see what is going on with a live drag, so you never know.

-J

[oc1]

Maybe the gripping gets hot.

[jurelometer]

Maybe the gripping gets hot.

CF composite does act a bit as an insulator, so I guess it is possible that one side gets a bit hotter than the other. But heat is supposed to decrease the CoF of dry carbon fiber drag washers, according to the Penn marketing material for their CF material.  And then if the drag is lubed, the grease viscosity will decrease with heat, further lowering the CoF. Thermal expansion is going to affect both sides more or less evenly. 

Tribology is so complicated.  I think the exact cause(s) will remain a mystery. But since the CoFs on both sides will typically be very close, it only takes a small change to swap sliding surfaces. The higher COF side will hold, even if the difference is quite small.

-J