DRAGENSTEIN

[richard]

  DRAGENSTEIN.   What this guy says seems to me to be at odds with what I
find in the real world.
I remember reading an example of place mats, with weight added, being dragger across the floor
to prove his point.
I,ve had a search but can't find the thread referring to this test.................can anyone help please?
            cheers

[Keta]

Is this it? 

http://alantani.com/index.php?topic=7652.0

http://tocatchafish.blogspot.com.au/p/fishing-reel-drags.html

[richard]

 yup that's the article,cheers Keta.
Maybe the bit I,m looking for is on another thread with reference to this Dragstein test.
It seemed to support the theory that it,s all about drag pressure and not surface area?
Something to do with putting weight on different sized place mats to prove this theory.

[theswimmer]

"One of those is that no drag washers, sealed or open, should be made from materials that are impregnated with grease.

This type of drag is always subject to change based on ambient temperatures.  I don't have to tell you the differences in temperatures between the deck of a flats skiff in the tropics and a tree limb rest on the bank of an Alaskan river.  These drags will never provide reproducible results.  As the ambient heat builds, the greases thin and the drag decreases.  As the ambient heat cools, the grease thickens and the drag pressure increases.  

The only reproducible results will be obtained from combinations of materials that perform under dry conditions, are not compressible (or only barely so), will not disintegrate, and that can be periodically cleaned of debris and crud.  (crud is the material that forms on the surface of the drag washers from friction and heat.)

Beyond these criteria, it makes little difference what the drag washer materials may actually be . . . with one not-so-small exception."

The above is from his blog.
http://tocatchafish.blogspot.com.au/p/blog-page.html
I don't know what his background is but his blog is full of conjecture and opinion not currently backed by data.
I will wait to see if he posts any verifiable hard data before drawing any conclusions.......
I especially like the definition of 'crud'

[Keta]

I've tested greased and dry drags by putting the reel in the freezer and the advantages of grease far out weigh the disadvantages and damage salt intrusion can cause to a reel with dry CF drag washers.  The "cure" to inconsistent drag pressures caused by temperature is the star or drag adjustment knob.

[richard]

I am 100% with you guys on greasing drag washers.Lower start up,waterproof,no ramp up, and they last about twice as
long before the reel starts to "stutter".They run cold or very hot.no brainer as far as I,m concerned.
This chap claims that surface area is not important,and its all about pressure on the drag.
If this were the case then putting extra plates in a drag would be a waste of time.
An avet RAPTOR would be no better than a normal AVET.
Twin caliper brakes on cars are pointless.

[theswimmer]

Brembo would produce 8 inch disks w/ single piston calipers and put them on every thing from an eighteen wheeler to a Mazda 2?
I think where he goes astray is the simple understanding of a drag being a type of heat engine, that is from an engineering standpoint  .
Same as disk brakes.

[Robert Janssen]

Richard, the thread you are looking for is here:

http://alantani.com/index.php?topic=4593.msg36161#msg36161

I will wait to see if he posts any verifiable hard data before drawing any conclusions.......

The Dragenstein article is seven or eight years old, so it is unlikely that will happen anytime soon.

.

[Tiddlerbasher]

Tribology is a weird science - literally! More surface area does not always result in more friction - ie drag in our case. Applied force and coeffient of friction are the big players.

The main flaw of the 'Dragenstein Project' was that the owner had his own patented product to sell to reel manufacturers (roulon, or similar, from memory). Also his actual testbed was a seemingly well designed and engineered machine but was it sufficiently 'reel' world

[johndtuttle]

we have been over this before and it is not at all the surface area that determines drag power, it is the radius of the washers (wider being better), the number of them (the more the merrier) and the number of active surfaces (ie keyed washers allowing both surfaces to be active.

After that, generally smoothness (grease) is more important than a small loss in max drag as well as corrosion protection.

[Tightlines667]

we have been over this before and it is not at all the surface area that determines drag power, it is the radius of the washers (wider being better), the number of them (the more the merrier) and the number of active surfaces (ie keyed washers allowing both surfaces to be active.

After that, generally smoothness (grease) is more important than a small loss in max drag as well as corrosion protection.

X2

Though I do believe that increased drag surface area can reduce wear slightly.

[theswimmer]

we have been over this before and it is not at all the surface area that determines drag power, it is the radius of the washers (wider being better), the number of them (the more the merrier) and the number of active surfaces (ie keyed washers allowing both surfaces to be active.

After that, generally smoothness (grease) is more important than a small loss in max drag as well as corrosion protection.




Totally agreed on both points ,however a disk brake and its components just like a reel drag remain a heat engine and the more surface area no mater how you achieve it allows a more rapid dissipation of heat and the greater increase in drag pressure and the increase in drag resistance #'s.
No mater what the conventional wisdom, data and drag #'s speak for themselves......

[jurelometer]

To the original post:

Look up 2nd law of friction on your favorite search engine.   Friction is independent of surface area. What matters is the amount of force and the slipperiness of the surfaces.  It is really counter-intuitive.  The classic example is dragging a brick across a table.   It doesn't matter which side  of the brick is  on the table.  It takes the same amount of force to move it, even though the sides have different surface areas.  The reason has to do with the the surfaces  not being  flat at the microscopic level.  If you double the surface area you might double the number of tiny contact points, but if the total force is not changed, the force per contact point is cut in half.  So you end up with the same amount of friction.  There is a more accurate  but complicated explanation of this phenomenon, but I don't understand it

From a strictly theoretical standpoint, adding  drag surfaces inside a reel increases the surface area, but does not change the force applied, or the coefficient of friction( slipperiness of the surfaces).      So this should mean that adding drag washers to a stack does not increase the amount of friction, so at a given amount of torque on the star,  the number of drag washers will not change  the actual amount of drag.

That does not mean that the drag stack does not perform better with more washers, or even that it might be possible to get a higher drag setting (perhaps by generating a better torque to lateral force translation).  But it does mean that any improvement in total drag for a given torque setting is not directly attributed to increasing the surface area.

Regarding diameter,  I think it works this way:   Going back to the brick analogy-   if you drag the brick around a  full circle,  the larger the circle, the greater the distance you have to drag the brick, thus converting more energy per rotation for a given amount of friction.   This presumes that the drag setting force can be applied to the outer diameter.  The larger the diameter, the trickier this can get.

In the end, we are converting kinetic energy ( motion) to heat.   IMHO we spend lots of  time thinking about how much heat we can generate ( max drag), and not so much, what to do with the heat.   Makes sense for setting up reels for quick stopping, but maybe not so much for extended runs.


-J.

[theswimmer]

Richard, the thread you are looking for is here:

http://alantani.com/index.php?topic=4593.msg36161#msg36161

I will wait to see if he posts any verifiable hard data before drawing any conclusions.......

The Dragenstein article is seven or eight years old, so it is unlikely that will happen anytime soon.

.

Ya I have emailed him several times when this was first posted with no response.....

[alantani]

follow the money......